--- /dev/null
+\r
+// \r
+// TODO:\r
+// - implement sin, asin, acos, atan, pow, log2, floor, ceil,\r
+// - implement texture1D, texture2D, texture3D, textureCube,\r
+// - implement shadow1D, shadow2D,\r
+// - implement noise1, noise2, noise3, noise4,\r
+// \r
+\r
+// \r
+// From Shader Spec, ver. 1.051\r
+// \r
+// The following built-in constants are provided to vertex and fragment shaders.\r
+// \r
+\r
+// \r
+// Implementation dependent constants. The example values below\r
+// are the minimum values allowed for these maximums.\r
+// \r
+\r
+const int gl_MaxLights = 8; // GL 1.0\r
+const int gl_MaxClipPlanes = 6; // GL 1.0\r
+const int gl_MaxTextureUnits = 2; // GL 1.2\r
+const int gl_MaxTextureCoordsARB = 2; // ARB_fragment_program\r
+const int gl_MaxVertexAttributesGL2 = 16; // GL2_vertex_shader\r
+const int gl_MaxVertexUniformFloatsGL2 = 512; // GL2_vertex_shader\r
+const int gl_MaxVaryingFloatsGL2 = 32; // GL2_vertex_shader\r
+const int gl_MaxVertexTextureUnitsGL2 = 1; // GL2_vertex_shader\r
+const int gl_MaxFragmentTextureUnitsGL2 = 2; // GL2_fragment_shader\r
+const int gl_MaxFragmentUniformFloatsGL2 = 64; // GL2_fragment_shader\r
+\r
+// \r
+// As an aid to accessing OpenGL processing state, the following uniform variables are built into\r
+// the OpenGL Shading Language. All page numbers and notations are references to the 1.4\r
+// specification.\r
+// \r
+\r
+// \r
+// Matrix state. p. 31, 32, 37, 39, 40.\r
+// \r
+\r
+uniform mat4 gl_ModelViewMatrix;\r
+uniform mat4 gl_ProjectionMatrix;\r
+uniform mat4 gl_ModelViewProjectionMatrix;\r
+uniform mat3 gl_NormalMatrix; // derived\r
+uniform mat4 gl_TextureMatrix[gl_MaxTextureCoordsARB];\r
+\r
+// \r
+// Normal scaling p. 39.\r
+// \r
+\r
+uniform float gl_NormalScale;\r
+\r
+// \r
+// Depth range in window coordinates, p. 33\r
+// \r
+\r
+struct gl_DepthRangeParameters {\r
+ float near; // n\r
+ float far; // f\r
+ float diff; // f - n\r
+};\r
+\r
+uniform gl_DepthRangeParameters gl_DepthRange;\r
+\r
+// \r
+// Clip planes p. 42.\r
+// \r
+\r
+uniform vec4 gl_ClipPlane[gl_MaxClipPlanes];\r
+\r
+// \r
+// Point Size, p. 66, 67.\r
+// \r
+\r
+struct gl_PointParameters {\r
+ float size;\r
+ float sizeMin;\r
+ float sizeMax;\r
+ float fadeThresholdSize;\r
+ float distanceConstantAttenuation;\r
+ float distanceLinearAttenuation;\r
+ float distanceQuadraticAttenuation;\r
+};\r
+\r
+uniform gl_PointParameters gl_Point;\r
+\r
+// \r
+// Material State p. 50, 55.\r
+// \r
+\r
+struct gl_MaterialParameters {\r
+ vec4 emission; // Ecm\r
+ vec4 ambient; // Acm\r
+ vec4 diffuse; // Dcm\r
+ vec4 specular; // Scm\r
+ float shininess; // Srm\r
+};\r
+\r
+uniform gl_MaterialParameters gl_FrontMaterial;\r
+uniform gl_MaterialParameters gl_BackMaterial;\r
+\r
+// \r
+// Light State p 50, 53, 55.\r
+// \r
+\r
+struct gl_LightSourceParameters {\r
+ vec4 ambient; // Acli\r
+ vec4 diffuse; // Dcli\r
+ vec4 specular; // Scli\r
+ vec4 position; // Ppli\r
+ vec4 halfVector; // Derived: Hi\r
+ vec3 spotDirection; // Sdli\r
+ float spotExponent; // Srli\r
+ float spotCutoff; // Crli\r
+ // (range: [0.0,90.0], 180.0)\r
+ float spotCosCutoff; // Derived: cos(Crli)\r
+ // (range: [1.0,0.0],-1.0)\r
+ float constantAttenuation; // K0\r
+ float linearAttenuation; // K1\r
+ float quadraticAttenuation; // K2\r
+};\r
+\r
+uniform gl_LightSourceParameters gl_LightSource[gl_MaxLights];\r
+\r
+struct gl_LightModelParameters {\r
+ vec4 ambient; // Acs\r
+};\r
+\r
+uniform gl_LightModelParameters gl_LightModel;\r
+\r
+// \r
+// Derived state from products of light and material.\r
+// \r
+\r
+struct gl_LightModelProducts {\r
+ vec4 sceneColor; // Derived. Ecm + Acm * Acs\r
+};\r
+\r
+uniform gl_LightModelProducts gl_FrontLightModelProduct;\r
+uniform gl_LightModelProducts gl_BackLightModelProduct;\r
+\r
+struct gl_LightProducts {\r
+ vec4 ambient; // Acm * Acli\r
+ vec4 diffuse; // Dcm * Dcli\r
+ vec4 specular; // Scm * Scli\r
+};\r
+\r
+uniform gl_LightProducts gl_FrontLightProduct[gl_MaxLights];\r
+uniform gl_LightProducts gl_BackLightProduct[gl_MaxLights];\r
+\r
+// \r
+// Textureg Environment and Generation, p. 152, p. 40-42.\r
+// \r
+\r
+uniform vec4 gl_TextureEnvColor[gl_MaxFragmentTextureUnitsGL2];\r
+uniform vec4 gl_EyePlaneS[gl_MaxTextureCoordsARB];\r
+uniform vec4 gl_EyePlaneT[gl_MaxTextureCoordsARB];\r
+uniform vec4 gl_EyePlaneR[gl_MaxTextureCoordsARB];\r
+uniform vec4 gl_EyePlaneQ[gl_MaxTextureCoordsARB];\r
+uniform vec4 gl_ObjectPlaneS[gl_MaxTextureCoordsARB];\r
+uniform vec4 gl_ObjectPlaneT[gl_MaxTextureCoordsARB];\r
+uniform vec4 gl_ObjectPlaneR[gl_MaxTextureCoordsARB];\r
+uniform vec4 gl_ObjectPlaneQ[gl_MaxTextureCoordsARB];\r
+\r
+// \r
+// Fog p. 161\r
+// \r
+\r
+struct gl_FogParameters {\r
+ vec4 color;\r
+ float density;\r
+ float start;\r
+ float end;\r
+ float scale; // 1 / (gl_FogEnd - gl_FogStart)\r
+};\r
+\r
+uniform gl_FogParameters gl_Fog;\r
+\r
+// \r
+// The OpenGL Shading Language defines an assortment of built-in convenience functions for scalar\r
+// and vector operations. Many of these built-in functions can be used in more than one type\r
+// of shader, but some are intended to provide a direct mapping to hardware and so are available\r
+// only for a specific type of shader.\r
+// \r
+// The built-in functions basically fall into three categories:\r
+// \r
+// \95 They expose some necessary hardware functionality in a convenient way such as accessing\r
+// a texture map. There is no way in the language for these functions to be emulated by a shader.\r
+// \r
+// \95 They represent a trivial operation (clamp, mix, etc.) that is very simple for the user\r
+// to write, but they are very common and may have direct hardware support. It is a very hard\r
+// problem for the compiler to map expressions to complex assembler instructions.\r
+// \r
+// \95 They represent an operation graphics hardware is likely to accelerate at some point. The\r
+// trigonometry functions fall into this category.\r
+// \r
+// Many of the functions are similar to the same named ones in common C libraries, but they support\r
+// vector input as well as the more traditional scalar input.\r
+// \r
+// Applications should be encouraged to use the built-in functions rather than do the equivalent\r
+// computations in their own shader code since the built-in functions are assumed to be optimal\r
+// (e.g., perhaps supported directly in hardware).\r
+// \r
+// User code can replace built-in functions with their own if they choose, by simply re-declaring\r
+// and defining the same name and argument list.\r
+// \r
+\r
+// \r
+// Angle and Trigonometry Functions\r
+// \r
+// Function parameters specified as angle are assumed to be in units of radians. In no case will\r
+// any of these functions result in a divide by zero error. If the divisor of a ratio is 0, then\r
+// results will be undefined.\r
+// \r
+// These all operate component-wise.\r
+// \r
+\r
+// \r
+// Converts degrees to radians and returns the result, i.e., result = PI*deg/180.\r
+// \r
+\r
+float radians (float deg) {\r
+ return 3.141593 * deg / 180.0;\r
+}\r
+vec2 radians (vec2 deg) {\r
+ return vec2 (radians (deg.x), radians (deg.y));\r
+}\r
+vec3 radians (vec3 deg) {\r
+ return vec3 (radians (deg.x), radians (deg.y), radians (deg.z));\r
+}\r
+vec4 radians (vec4 deg) {\r
+ return vec4 (radians (deg.x), radians (deg.y), radians (deg.z), radians (deg.w));\r
+}\r
+\r
+// \r
+// Converts radians to degrees and returns the result, i.e., result = 180*rad/PI.\r
+// \r
+\r
+float degrees (float rad) {\r
+ return 180.0 * rad / 3.141593;\r
+}\r
+vec2 degrees (vec2 rad) {\r
+ return vec2 (degrees (rad.x), degrees (rad.y));\r
+}\r
+vec3 degrees (vec3 rad) {\r
+ return vec3 (degrees (rad.x), degrees (rad.y), degrees (rad.z));\r
+}\r
+vec4 degrees (vec4 rad) {\r
+ return vec4 (degrees (rad.x), degrees (rad.y), degrees (rad.z), degrees (rad.w));\r
+}\r
+\r
+// \r
+// The standard trigonometric sine function.\r
+// \r
+// XXX\r
+float sin (float angle) {\r
+ return 0.0;\r
+}\r
+vec2 sin (vec2 angle) {\r
+ return vec2 (sin (angle.x), sin (angle.y));\r
+}\r
+vec3 sin (vec3 angle) {\r
+ return vec3 (sin (angle.x), sin (angle.y), sin (angle.z));\r
+}\r
+vec4 sin (vec4 angle) {\r
+ return vec4 (sin (angle.x), sin (angle.y), sin (angle.z), sin (angle.w));\r
+}\r
+\r
+// \r
+// The standard trigonometric cosine function.\r
+// \r
+\r
+float cos (float angle) {\r
+ return sin (angle + 1.5708);\r
+}\r
+vec2 cos (vec2 angle) {\r
+ return vec2 (cos (angle.x), cos (angle.y));\r
+}\r
+vec3 cos (vec3 angle) {\r
+ return vec3 (cos (angle.x), cos (angle.y), cos (angle.z));\r
+}\r
+vec4 cos (vec4 angle) {\r
+ return vec4 (cos (angle.x), cos (angle.y), cos (angle.z), cos (angle.w));\r
+}\r
+\r
+// \r
+// The standard trigonometric tangent.\r
+// \r
+\r
+float tan (float angle) {\r
+ return sin (angle) / cos (angle);\r
+}\r
+vec2 tan (vec2 angle) {\r
+ return vec2 (tan (angle.x), tan (angle.y));\r
+}\r
+vec3 tan (vec3 angle) {\r
+ return vec3 (tan (angle.x), tan (angle.y), tan (angle.z));\r
+}\r
+vec4 tan (vec4 angle) {\r
+ return vec4 (tan (angle.x), tan (angle.y), tan (angle.z), tan (angle.w));\r
+}\r
+\r
+// \r
+// Arc sine. Returns an angle whose sine is x. The range of values returned by this function is\r
+// [\96PI/2, PI/2]. Results are undefined if |x| > 1.\r
+// \r
+// XXX\r
+float asin (float x) {\r
+ return 0.0;\r
+}\r
+vec2 asin (vec2 x) {\r
+ return vec2 (asin (x.x), asin (x.y));\r
+}\r
+vec3 asin (vec3 x) {\r
+ return vec3 (asin (x.x), asin (x.y), asin (x.z));\r
+}\r
+vec4 asin (vec4 x) {\r
+ return vec4 (asin (x.x), asin (x.y), asin (x.z), asin (x.w));\r
+}\r
+\r
+// \r
+// Arc cosine. Returns an angle whose cosine is x. The range of values returned by this function is\r
+// [0, PI]. Results are undefined if |x| > 1.\r
+// \r
+// XXX\r
+float acos (float x) {\r
+ return 0.0;\r
+}\r
+vec2 acos (vec2 x) {\r
+ return vec2 (acos (x.x), acos (x.y));\r
+}\r
+vec3 acos (vec3 x) {\r
+ return vec3 (acos (x.x), acos (x.y), acos (x.z));\r
+}\r
+vec4 acos (vec4 x) {\r
+ return vec4 (acos (x.x), acos (x.y), acos (x.z), acos (x.w));\r
+}\r
+\r
+// \r
+// Arc tangent. Returns an angle whose tangent is y/x. The signs of x and y are used to determine\r
+// what quadrant the angle is in. The range of values returned by this function is [\96PI, PI].\r
+// Results are undefined if x and y are both 0.\r
+// \r
+// XXX\r
+float atan (float x, float y) {\r
+ return 0.0;\r
+}\r
+vec2 atan (vec2 x, vec2 y) {\r
+ return vec2 (atan (x.x, y.x), atan (x.y, y.y));\r
+}\r
+vec3 atan (vec3 x, vec3 y) {\r
+ return vec3 (atan (x.x, y.x), atan (x.y, y.y), atan (x.z, y.z));\r
+}\r
+vec4 atan (vec4 x, vec4 y) {\r
+ return vec4 (atan (x.x, y.x), atan (x.y, y.y), atan (x.z, y.z), atan (x.w, y.w));\r
+}\r
+\r
+// \r
+// Arc tangent. Returns an angle whose tangent is y_over_x. The range of values returned by this\r
+// function is [\96PI/2, PI/2].\r
+// \r
+// XXX\r
+float atan (float y_over_x) {\r
+ return 0.0;\r
+}\r
+vec2 atan (vec2 y_over_x) {\r
+ return vec2 (atan (y_over_x.x), atan (y_over_x.y));\r
+}\r
+vec3 atan (vec3 y_over_x) {\r
+ return vec3 (atan (y_over_x.x), atan (y_over_x.y), atan (y_over_x.z));\r
+}\r
+vec4 atan (vec4 y_over_x) {\r
+ return vec4 (atan (y_over_x.x), atan (y_over_x.y), atan (y_over_x.z), atan (y_over_x.w));\r
+}\r
+\r
+// \r
+// Exponential Functions\r
+// \r
+// These all operate component-wise.\r
+// \r
+\r
+// \r
+// Returns x raised to the y power, i.e., x^y\r
+// \r
+// XXX\r
+float pow (float x, float y) {\r
+ return 0.0;\r
+}\r
+vec2 pow (vec2 x, vec2 y) {\r
+ return vec2 (pow (x.x, y.x), pow (x.y, y.y));\r
+}\r
+vec3 pow (vec3 x, vec3 y) {\r
+ return vec3 (pow (x.x, y.x), pow (x.y, y.y), pow (x.z, y.z));\r
+}\r
+vec4 pow (vec4 x, vec4 y) {\r
+ return vec4 (pow (x.x, y.x), pow (x.y, y.y), pow (x.z, y.z), pow (x.w, y.w));\r
+}\r
+\r
+// \r
+// Returns 2 raised to the x power, i.e., 2^x\r
+// \r
+\r
+float exp2 (float x) {\r
+ return pow (2.0, x);\r
+}\r
+vec2 exp2 (vec2 x) {\r
+ return vec2 (exp2 (x.x), exp2 (x.y));\r
+}\r
+vec3 exp2 (vec3 x) {\r
+ return vec3 (exp2 (x.x), exp2 (x.y), exp2 (x.z));\r
+}\r
+vec4 exp2 (vec4 x) {\r
+ return vec4 (exp2 (x.x), exp2 (x.y), exp2 (x.z), exp2 (x.w));\r
+}\r
+\r
+// \r
+// Returns the base 2 log of x, i.e., returns the value y which satisfies the equation x = 2^y\r
+// \r
+// XXX\r
+float log2 (float x) {\r
+ return 0.0;\r
+}\r
+vec2 log2 (vec2 x) {\r
+ return vec2 (log2 (x.x), log2 (x.y));\r
+}\r
+vec3 log2 (vec3 x) {\r
+ return vec3 (log2 (x.x), log2 (x.y), log2 (x.z));\r
+}\r
+vec4 log2 (vec4 x) {\r
+ return vec4 (log2 (x.x), log2 (x.y), log2 (x.z), log2 (x.w));\r
+}\r
+\r
+// \r
+// Returns the positive square root of x\r
+// \r
+\r
+float sqrt (float x) {\r
+ return pow (x, 0.5);\r
+}\r
+vec2 sqrt (vec2 x) {\r
+ return vec2 (sqrt (x.x), sqrt (x.y));\r
+}\r
+vec3 sqrt (vec3 x) {\r
+ return vec3 (sqrt (x.x), sqrt (x.y), sqrt (x.z));\r
+}\r
+vec4 sqrt (vec4 x) {\r
+ return vec4 (sqrt (x.x), sqrt (x.y), sqrt (x.z), sqrt (x.w));\r
+}\r
+\r
+// \r
+// Returns the reciprocal of the positive square root of x\r
+// \r
+\r
+float inversesqrt (float x) {\r
+ return 1.0 / sqrt (x);\r
+}\r
+vec2 inversesqrt (vec2 x) {\r
+ return vec2 (inversesqrt (x.x), inversesqrt (x.y));\r
+}\r
+vec3 inversesqrt (vec3 x) {\r
+ return vec3 (inversesqrt (x.x), inversesqrt (x.y), inversesqrt (x.z));\r
+}\r
+vec4 inversesqrt (vec4 x) {\r
+ return vec4 (inversesqrt (x.x), inversesqrt (x.y), inversesqrt (x.z), inversesqrt (x.w));\r
+}\r
+\r
+// \r
+// Common Functions\r
+// \r
+// These all operate component-wise.\r
+// \r
+\r
+// \r
+// Returns x if x >= 0, otherwise it returns \96x\r
+// \r
+\r
+float abs (float x) {\r
+ return x >= 0.0 ? x : -x;\r
+}\r
+vec2 abs (vec2 x) {\r
+ return vec2 (abs (x.x), abs (x.y));\r
+}\r
+vec3 abs (vec3 x) {\r
+ return vec3 (abs (x.x), abs (x.y), abs (x.z));\r
+}\r
+vec4 abs (vec4 x) {\r
+ return vec4 (abs (x.x), abs (x.y), abs (x.z), abs (x.w));\r
+}\r
+\r
+// \r
+// Returns 1.0 if x > 0, 0.0 if x = 0, or \961.0 if x < 0\r
+// \r
+\r
+float sign (float x) {\r
+ return x > 0.0 ? 1.0 : x < 0.0 ? -1.0 : 0.0;\r
+}\r
+vec2 sign (vec2 x) {\r
+ return vec2 (sign (x.x), sign (x.y));\r
+}\r
+vec3 sign (vec3 x) {\r
+ return vec3 (sign (x.x), sign (x.y), sign (x.z));\r
+}\r
+vec4 sign (vec4 x) {\r
+ return vec4 (sign (x.x), sign (x.y), sign (x.z), sign (x.w));\r
+}\r
+\r
+// \r
+// Returns a value equal to the nearest integer that is less than or equal to x\r
+// \r
+// XXX\r
+float floor (float x) {\r
+ return 0.0;\r
+}\r
+vec2 floor (vec2 x) {\r
+ return vec2 (floor (x.x), floor (x.y));\r
+}\r
+vec3 floor (vec3 x) {\r
+ return vec3 (floor (x.x), floor (x.y), floor (x.z));\r
+}\r
+vec4 floor (vec4 x) {\r
+ return vec4 (floor (x.x), floor (x.y), floor (x.z), floor (x.w));\r
+}\r
+\r
+// \r
+// Returns a value equal to the nearest integer that is greater than or equal to x\r
+// \r
+// XXX\r
+float ceil (float x) {\r
+ return 0.0;\r
+}\r
+vec2 ceil (vec2 x) {\r
+ return vec2 (ceil (x.x), ceil (x.y));\r
+}\r
+vec3 ceil (vec3 x) {\r
+ return vec3 (ceil (x.x), ceil (x.y), ceil (x.z));\r
+}\r
+vec4 ceil (vec4 x) {\r
+ return vec4 (ceil (x.x), ceil (x.y), ceil (x.z), ceil (x.w));\r
+}\r
+\r
+// \r
+// Returns x \96 floor (x)\r
+// \r
+\r
+float fract (float x) {\r
+ return x - floor (x);\r
+}\r
+vec2 fract (vec2 x) {\r
+ return vec2 (fract (x.x), fract (x.y));\r
+}\r
+vec3 fract (vec3 x) {\r
+ return vec3 (fract (x.x), fract (x.y), fract (x.z));\r
+}\r
+vec4 fract (vec4 x) {\r
+ return vec4 (fract (x.x), fract (x.y), fract (x.z), fract (x.w));\r
+}\r
+\r
+// \r
+// Modulus. Returns x \96 y * floor (x/y)\r
+// \r
+\r
+float mod (float x, float y) {\r
+ return x - y * floor (x / y);\r
+}\r
+vec2 mod (vec2 x, float y) {\r
+ return vec2 (mod (x.x, y), mod (x.y, y));\r
+}\r
+vec3 mod (vec3 x, float y) {\r
+ return vec3 (mod (x.x, y), mod (x.y, y), mod (x.z, y));\r
+}\r
+vec4 mod (vec4 x, float y) {\r
+ return vec4 (mod (x.x, y), mod (x.y, y), mod (x.z, y), mod (x.w, y));\r
+}\r
+vec2 mod (vec2 x, vec2 y) {\r
+ return vec2 (mod (x.x, y.x), mod (x.y, y.y));\r
+}\r
+vec3 mod (vec3 x, vec3 y) {\r
+ return vec3 (mod (x.x, y.x), mod (x.y, y.y), mod (x.z, y.z));\r
+}\r
+vec4 mod (vec4 x, vec4 y) {\r
+ return vec4 (mod (x.x, y.x), mod (x.y, y.y), mod (x.z, y.z), mod (x.w, y.w));\r
+}\r
+\r
+// \r
+// Returns y if y < x, otherwise it returns x\r
+// \r
+\r
+float min (float x, float y) {\r
+ return y < x ? y : x;\r
+}\r
+vec2 min (vec2 x, float y) {\r
+ return vec2 (min (x.x, y), min (x.y, y));\r
+}\r
+vec3 min (vec3 x, float y) {\r
+ return vec3 (min (x.x, y), min (x.y, y), min (x.z, y));\r
+}\r
+vec4 min (vec4 x, float y) {\r
+ return vec4 (min (x.x, y), min (x.y, y), min (x.z, y), min (x.w, y));\r
+}\r
+vec2 min (vec2 x, vec2 y) {\r
+ return vec2 (min (x.x, y.x), min (x.y, y.y));\r
+}\r
+vec3 min (vec3 x, vec3 y) {\r
+ return vec3 (min (x.x, y.x), min (x.y, y.y), min (x.z, y.z));\r
+}\r
+vec4 min (vec4 x, vec4 y) {\r
+ return vec4 (min (x.x, y.x), min (x.y, y.y), min (x.z, y.z), min (x.w, y.w));\r
+}\r
+\r
+// \r
+// Returns y if x < y, otherwise it returns x\r
+// \r
+\r
+float max (float x, float y) {\r
+ return min (y, x);\r
+}\r
+vec2 max (vec2 x, float y) {\r
+ return vec2 (max (x.x, y), max (x.y, y));\r
+}\r
+vec3 max (vec3 x, float y) {\r
+ return vec3 (max (x.x, y), max (x.y, y), max (x.z, y));\r
+}\r
+vec4 max (vec4 x, float y) {\r
+ return vec4 (max (x.x, y), max (x.y, y), max (x.z, y), max (x.w, y));\r
+}\r
+vec2 max (vec2 x, vec2 y) {\r
+ return vec2 (max (x.x, y.x), max (x.y, y.y));\r
+}\r
+vec3 max (vec3 x, vec3 y) {\r
+ return vec3 (max (x.x, y.x), max (x.y, y.y), max (x.z, y.z));\r
+}\r
+vec4 max (vec4 x, vec4 y) {\r
+ return vec4 (max (x.x, y.x), max (x.y, y.y), max (x.z, y.z), max (x.w, y.w));\r
+}\r
+\r
+// \r
+// Returns min (max (x, minVal), maxVal)\r
+// \r
+// Note that colors and depths written by fragment shaders will be clamped by the implementation\r
+// after the fragment shader runs.\r
+// \r
+\r
+float clamp (float x, float minVal, float maxVal) {\r
+ return min (max (x, minVal), maxVal);\r
+}\r
+vec2 clamp (vec2 x, float minVal, float maxVal) {\r
+ return vec2 (clamp (x.x, minVal, maxVal), clamp (x.y, minVal, maxVal));\r
+}\r
+vec3 clamp (vec3 x, float minVal, float maxVal) {\r
+ return vec3 (clamp (x.x, minVal, maxVal), clamp (x.y, minVal, maxVal),\r
+ clamp (x.z, minVal, maxVal));\r
+}\r
+vec4 clamp (vec4 x, float minVal, float maxVal) {\r
+ return vec4 (clamp (x.x, minVal, maxVal), clamp (x.y, minVal, maxVal),\r
+ clamp (x.z, minVal, maxVal), clamp (x.w, minVal, maxVal));\r
+}\r
+vec2 clamp (vec2 x, vec2 minVal, vec2 maxVal) {\r
+ return vec2 (clamp (x.x, minVal.x, maxVal.x), clamp (x.y, minVal.y, maxVal.y));\r
+}\r
+vec3 clamp (vec3 x, vec3 minVal, vec3 maxVal) {\r
+ return vec3 (clamp (x.x, minVal.x, maxVal.x), clamp (x.y, minVal.y, maxVal.y),\r
+ clamp (x.z, minVal.z, maxVal.z));\r
+}\r
+vec4 clamp (vec4 x, vec4 minVal, vec4 maxVal) {\r
+ return vec4 (clamp (x.x, minVal.x, maxVal.y), clamp (x.y, minVal.y, maxVal.y),\r
+ clamp (x.z, minVal.z, maxVal.z), clamp (x.w, minVal.w, maxVal.w));\r
+}\r
+\r
+// \r
+// Returns x * (1 \96 a) + y * a, i.e., the linear blend of x and y\r
+// \r
+\r
+float mix (float x, float y, float a) {\r
+ return x * (1.0 - a) + y * a;\r
+}\r
+vec2 mix (vec2 x, vec2 y, float a) {\r
+ return vec2 (mix (x.x, y.x, a), mix (x.y, y.y, a));\r
+}\r
+vec3 mix (vec3 x, vec3 y, float a) {\r
+ return vec3 (mix (x.x, y.x, a), mix (x.y, y.y, a), mix (x.z, y.z, a));\r
+}\r
+vec4 mix (vec4 x, vec4 y, float a) {\r
+ return vec4 (mix (x.x, y.x, a), mix (x.y, y.y, a), mix (x.z, y.z, a), mix (x.w, y.w, a));\r
+}\r
+vec2 mix (vec2 x, vec2 y, vec2 a) {\r
+ return vec2 (mix (x.x, y.x, a.x), mix (x.y, y.y, a.y));\r
+}\r
+vec3 mix (vec3 x, vec3 y, vec3 a) {\r
+ return vec3 (mix (x.x, y.x, a.x), mix (x.y, y.y, a.y), mix (x.z, y.z, a.z));\r
+}\r
+vec4 mix (vec4 x, vec4 y, vec4 a) {\r
+ return vec4 (mix (x.x, y.x, a.x), mix (x.y, y.y, a.y), mix (x.z, y.z, a.z),\r
+ mix (x.w, y.w, a.w));\r
+}\r
+\r
+// \r
+// Returns 0.0 if x <= edge, otherwise it returns 1.0\r
+// \r
+\r
+float step (float edge, float x) {\r
+ return x <= edge ? 0.0 : 1.0;\r
+}\r
+vec2 step (float edge, vec2 x) {\r
+ return vec2 (step (edge, x.x), step (edge, x.y));\r
+}\r
+vec3 step (float edge, vec3 x) {\r
+ return vec3 (step (edge, x.x), step (edge, x.y), step (edge, x.z));\r
+}\r
+vec4 step (float edge, vec4 x) {\r
+ return vec4 (step (edge, x.x), step (edge, x.y), step (edge, x.z), step (edge, x.w));\r
+}\r
+vec2 step (vec2 edge, vec2 x) {\r
+ return vec2 (step (edge.x, x.x), step (edge.y, x.y));\r
+}\r
+vec3 step (vec3 edge, vec3 x) {\r
+ return vec3 (step (edge.x, x.x), step (edge.y, x.y), step (edge.z, x.z));\r
+}\r
+vec4 step (vec4 edge, vec4 x) {\r
+ return vec4 (step (edge.x, x.x), step (edge.y, x.y), step (edge.z, x.z), step (edge.w, x.w));\r
+}\r
+\r
+// \r
+// Returns 0.0 if x <= edge0 and 1.0 if x >= edge1 and performs smooth Hermite interpolation\r
+// between 0 and 1 when edge0 < x < edge1. This is useful in cases where you would want a threshold\r
+// function with a smooth transition. This is equivalent to:\r
+// <type> t;\r
+// t = clamp ((x \96 edge0) / (edge1 \96 edge0), 0, 1);\r
+// return t * t * (3 \96 2 * t);\r
+// \r
+\r
+float smoothstep (float edge0, float edge1, float x) {\r
+ const float t = clamp ((x - edge0) / (edge1 - edge0), 0.0, 1.0);\r
+ return t * t * (3.0 - 2.0 * t);\r
+}\r
+vec2 smoothstep (float edge0, float edge1, vec2 x) {\r
+ return vec2 (smoothstep (edge0, edge1, x.x), smoothstep (edge0, edge1, x.y));\r
+}\r
+vec3 smoothstep (float edge0, float edge1, vec3 x) {\r
+ return vec3 (smoothstep (edge0, edge1, x.x), smoothstep (edge0, edge1, x.y),\r
+ smoothstep (edge0, edge1, x.z));\r
+}\r
+vec4 smoothstep (float edge0, float edge1, vec4 x) {\r
+ return vec4 (smoothstep (edge0, edge1, x.x), smoothstep (edge0, edge1, x.y),\r
+ smoothstep (edge0, edge1, x.z), smoothstep (edge0, edge1, x.w));\r
+}\r
+vec2 smoothstep (vec2 edge0, vec2 edge1, vec2 x) {\r
+ return vec2 (smoothstep (edge0.x, edge1.x, x.x), smoothstep (edge0.y, edge1.y, x.y));\r
+}\r
+vec3 smoothstep (vec3 edge0, vec3 edge1, vec3 x) {\r
+ return vec3 (smoothstep (edge0.x, edge1.x, x.x), smoothstep (edge0.y, edge1.y, x.y),\r
+ smoothstep (edge0.z, edge1.z, x.z));\r
+}\r
+vec4 smoothstep (vec4 edge0, vec4 edge1, vec4 x) {\r
+ return vec4 (smoothstep (edge0.x, edge1.x, x.x), smoothstep (edge0.y, edge1.y, x.y),\r
+ smoothstep (edge0.z, edge1.z, x.z), smoothstep (edge0.w, edge1.w, x.w));\r
+}\r
+\r
+// \r
+// Geometric Functions\r
+// \r
+// These operate on vectors as vectors, not component-wise.\r
+// \r
+\r
+// \r
+// Returns the dot product of x and y, i.e., result = x[0] * y[0] + x[1] * y[1] + ...\r
+// \r
+\r
+float dot (float x, float y) {\r
+ return x * y;\r
+}\r
+float dot (vec2 x, vec2 y) {\r
+ return dot (x.x, y.x) + dot (x.y, y.y);\r
+}\r
+float dot (vec3 x, vec3 y) {\r
+ return dot (x.x, y.x) + dot (x.y, y.y) + dot (x.z, y.z);\r
+}\r
+float dot (vec4 x, vec4 y) {\r
+ return dot (x.x, y.x) + dot (x.y, y.y) + dot (x.z, y.z) + dot (x.w, y.w);\r
+}\r
+\r
+// \r
+// Returns the length of vector x, i.e., sqrt (x[0] * x[0] + x[1] * x[1] + ...)\r
+// \r
+\r
+float length (float x) {\r
+ return sqrt (dot (x, x));\r
+}\r
+float length (vec2 x) {\r
+ return sqrt (dot (x, x));\r
+}\r
+float length (vec3 x) {\r
+ return sqrt (dot (x, x));\r
+}\r
+float length (vec4 x) {\r
+ return sqrt (dot (x, x));\r
+}\r
+\r
+// \r
+// Returns the distance between p0 and p1, i.e. length (p0 \96 p1)\r
+// \r
+\r
+float distance (float x, float y) {\r
+ return length (x - y);\r
+}\r
+float distance (vec2 x, vec2 y) {\r
+ return length (x - y);\r
+}\r
+float distance (vec3 x, vec3 y) {\r
+ return length (x - y);\r
+}\r
+float distance (vec4 x, vec4 y) {\r
+ return length (x - y);\r
+}\r
+\r
+// \r
+// Returns the cross product of x and y, i.e.\r
+// result.0 = x[1] * y[2] - y[1] * x[2]\r
+// result.1 = x[2] * y[0] - y[2] * x[0]\r
+// result.2 = x[0] * y[1] - y[0] * x[1]\r
+// \r
+\r
+vec3 cross (vec3 x, vec3 y) {\r
+ return vec3 (x.y * y.z - y.y * x.z, x.z * y.x - y.z * x.x, x.x * y.y - y.x * x.y);\r
+}\r
+\r
+// \r
+// Returns a vector in the same direction as x but with a length of 1.\r
+// \r
+\r
+float normalize (float x) {\r
+ return 1.0;\r
+}\r
+vec2 normalize (vec2 x) {\r
+ return x / length (x);\r
+}\r
+vec3 normalize (vec3 x) {\r
+ return x / length (x);\r
+}\r
+vec4 normalize (vec4 x) {\r
+ return x / length (x);\r
+}\r
+\r
+// \r
+// If dot (Nref, I) < 0 return N otherwise return \96N\r
+// \r
+\r
+float faceforward (float N, float I, float Nref) {\r
+ return dot (Nref, I) < 0.0 ? N : -N;\r
+}\r
+vec2 faceforward (vec2 N, vec2 I, vec2 Nref) {\r
+ return dot (Nref, I) < 0.0 ? N : -N;\r
+}\r
+vec3 faceforward (vec3 N, vec3 I, vec3 Nref) {\r
+ return dot (Nref, I) < 0.0 ? N : -N;\r
+}\r
+vec4 faceforward (vec4 N, vec4 I, vec4 Nref) {\r
+ return dot (Nref, I) < 0.0 ? N : -N;\r
+}\r
+\r
+// \r
+// For the incident vector I and surface orientation N, returns the reflection direction:\r
+// result = I \96 2 * dot (N, I) * N\r
+// N should be normalized in order to achieve the desired result.\r
+\r
+float reflect (float I, float N) {\r
+ return I - 2.0 * dot (N, I) * N;\r
+}\r
+vec2 reflect (vec2 I, vec2 N) {\r
+ return I - 2.0 * dot (N, I) * N;\r
+}\r
+vec3 reflect (vec3 I, vec3 N) {\r
+ return I - 2.0 * dot (N, I) * N;\r
+}\r
+vec4 reflect (vec4 I, vec4 N) {\r
+ return I - 2.0 * dot (N, I) * N;\r
+}\r
+\r
+// \r
+// Matrix Functions\r
+// \r
+\r
+// \r
+// Multiply matrix x by matrix y component-wise, i.e., result[i][j] is the scalar product\r
+// of x[i][j] and y[i][j].\r
+// Note: to get linear algebraic matrix multiplication, use the multiply operator (*).\r
+// \r
+\r
+mat2 matrixCompMult (mat2 x, mat2 y) {\r
+ return mat2 (\r
+ x[0].x * y[0].x, x[0].y * y[0].y,\r
+ x[1].x * y[1].x, x[1].y * y[1].y\r
+ );\r
+}\r
+mat3 matrixCompMult (mat3 x, mat3 y) {\r
+ return mat4 (\r
+ x[0].x * y[0].x, x[0].y * y[0].y, x[0].z * y[0].z,\r
+ x[1].x * y[1].x, x[1].y * y[1].y, x[1].z * y[1].z,\r
+ x[2].x * y[2].x, x[2].y * y[2].y, x[2].z * y[2].z\r
+ );\r
+}\r
+mat4 matrixCompMult (mat4 x, mat4 y) {\r
+ return mat4 (\r
+ x[0].x * y[0].x, x[0].y * y[0].y, x[0].z * y[0].z + x[0].w * y[0].w,\r
+ x[1].x * y[1].x, x[1].y * y[1].y, x[1].z * y[1].z + x[1].w * y[1].w,\r
+ x[2].x * y[2].x, x[2].y * y[2].y, x[2].z * y[2].z + x[2].w * y[2].w,\r
+ x[3].x * y[3].x, x[3].y * y[3].y, x[3].z * y[3].z + x[3].w * y[3].w\r
+ );\r
+}\r
+\r
+// \r
+// Vector Relational Functions\r
+// \r
+// Relational and equality operators (<, <=, >, >=, ==, !=) are defined (or reserved) to produce\r
+// scalar Boolean results.\r
+// \r
+\r
+// \r
+// Returns the component-wise compare of x < y.\r
+// \r
+\r
+bvec2 lessThan (vec2 x, vec2 y) {\r
+ return bvec2 (x.x < y.x, x.y < y.y);\r
+}\r
+bvec3 lessThan (vec3 x, vec3 y) {\r
+ return bvec3 (x.x < y.x, x.y < y.y, x.z < y.z);\r
+}\r
+bvec4 lessThan (vec4 x, vec4 y) {\r
+ return bvec4 (x.x < y.x, x.y < y.y, x.z < y.z, x.w < y.w);\r
+}\r
+bvec2 lessThan (ivec2 x, ivec2 y) {\r
+ return bvec2 (x.x < y.x, x.y < y.y);\r
+}\r
+bvec3 lessThan (ivec3 x, ivec3 y) {\r
+ return bvec3 (x.x < y.x, x.y < y.y, x.z < y.z);\r
+}\r
+bvec4 lessThan (ivec4 x, ivec4 y) {\r
+ return bvec4 (x.x < y.x, x.y < y.y, x.z < y.z, x.w < y.w);\r
+}\r
+\r
+// \r
+// Returns the component-wise compare of x <= y.\r
+// \r
+\r
+bvec2 lessThanEqual (vec2 x, vec2 y) {\r
+ return bvec2 (x.x <= y.x, x.y <= y.y);\r
+}\r
+bvec3 lessThanEqual (vec3 x, vec3 y) {\r
+ return bvec3 (x.x <= y.x, x.y <= y.y, x.z <= y.z);\r
+}\r
+bvec4 lessThanEqual (vec4 x, vec4 y) {\r
+ return bvec4 (x.x <= y.x, x.y <= y.y, x.z <= y.z, x.w <= y.w);\r
+}\r
+bvec2 lessThanEqual (ivec2 x, ivec2 y) {\r
+ return bvec2 (x.x <= y.x, x.y <= y.y);\r
+}\r
+bvec3 lessThanEqual (ivec3 x, ivec3 y) {\r
+ return bvec3 (x.x <= y.x, x.y <= y.y, x.z <= y.z);\r
+}\r
+bvec4 lessThanEqual (ivec4 x, ivec4 y) {\r
+ return bvec4 (x.x <= y.x, x.y <= y.y, x.z <= y.z, x.w <= y.w);\r
+}\r
+\r
+// \r
+// Returns the component-wise compare of x > y.\r
+// \r
+\r
+bvec2 greaterThan (vec2 x, vec2 y) {\r
+ return bvec2 (x.x > y.x, x.y > y.y);\r
+}\r
+bvec3 greaterThan (vec3 x, vec3 y) {\r
+ return bvec3 (x.x > y.x, x.y > y.y, x.z > y.z);\r
+}\r
+bvec4 greaterThan (vec4 x, vec4 y) {\r
+ return bvec4 (x.x > y.x, x.y > y.y, x.z > y.z, x.w > y.w);\r
+}\r
+bvec2 greaterThan (ivec2 x, ivec2 y) {\r
+ return bvec2 (x.x > y.x, x.y > y.y);\r
+}\r
+bvec3 greaterThan (ivec3 x, ivec3 y) {\r
+ return bvec3 (x.x > y.x, x.y > y.y, x.z > y.z);\r
+}\r
+bvec4 greaterThan (ivec4 x, ivec4 y) {\r
+ return bvec4 (x.x > y.x, x.y > y.y, x.z > y.z, x.w > y.w);\r
+}\r
+\r
+// \r
+// Returns the component-wise compare of x >= y.\r
+// \r
+\r
+bvec2 greaterThanEqual (vec2 x, vec2 y) {\r
+ return bvec2 (x.x >= y.x, x.y >= y.y);\r
+}\r
+bvec3 greaterThanEqual (vec3 x, vec3 y) {\r
+ return bvec3 (x.x >= y.x, x.y >= y.y, x.z >= y.z);\r
+}\r
+bvec4 greaterThanEqual (vec4 x, vec4 y) {\r
+ return bvec4 (x.x >= y.x, x.y >= y.y, x.z >= y.z, x.w >= y.w);\r
+}\r
+bvec2 greaterThanEqual (ivec2 x, ivec2 y) {\r
+ return bvec2 (x.x >= y.x, x.y >= y.y);\r
+}\r
+bvec3 greaterThanEqual (ivec3 x, ivec3 y) {\r
+ return bvec3 (x.x >= y.x, x.y >= y.y, x.z >= y.z);\r
+}\r
+bvec4 greaterThanEqual (ivec4 x, ivec4 y) {\r
+ return bvec4 (x.x >= y.x, x.y >= y.y, x.z >= y.z, x.w >= y.w);\r
+}\r
+\r
+// \r
+// Returns the component-wise compare of x == y.\r
+// \r
+\r
+bvec2 equal (vec2 x, vec2 y) {\r
+ return bvec2 (x.x == y.x, x.y == y.y);\r
+}\r
+bvec3 equal (vec3 x, vec3 y) {\r
+ return bvec3 (x.x == y.x, x.y == y.y, x.z == y.z);\r
+}\r
+bvec4 equal (vec4 x, vec4 y) {\r
+ return bvec4 (x.x == y.x, x.y == y.y, x.z == y.z, x.w == y.w);\r
+}\r
+bvec2 equal (ivec2 x, ivec2 y) {\r
+ return bvec2 (x.x == y.x, x.y == y.y);\r
+}\r
+bvec3 equal (ivec3 x, ivec3 y) {\r
+ return bvec3 (x.x == y.x, x.y == y.y, x.z == y.z);\r
+}\r
+bvec4 equal (ivec4 x, ivec4 y) {\r
+ return bvec4 (x.x == y.x, x.y == y.y, x.z == y.z, x.w == y.w);\r
+}\r
+\r
+// \r
+// Returns the component-wise compare of x != y.\r
+// \r
+\r
+bvec2 notEqual (vec2 x, vec2 y) {\r
+ return bvec2 (x.x != y.x, x.y != y.y);\r
+}\r
+bvec3 notEqual (vec3 x, vec3 y) {\r
+ return bvec3 (x.x != y.x, x.y != y.y, x.z != y.z);\r
+}\r
+bvec4 notEqual (vec4 x, vec4 y) {\r
+ return (bvec4 (x.x != y.x, x.y != y.y, x.z != y.z, x.w != y.w);\r
+}\r
+bvec2 notEqual (ivec2 x, ivec2 y) {\r
+ return (bvec2 (x.x != y.x, x.y != y.y);\r
+}\r
+bvec3 notEqual (ivec3 x, ivec3 y) {\r
+ return (bvec3 (x.x != y.x, x.y != y.y, x.z != y.z);\r
+}\r
+bvec4 notEqual (ivec4 x, ivec4 y) {\r
+ return (bvec4 (x.x != y.x, x.y != y.y, x.z != y.z, x.w != y.w);\r
+}\r
+\r
+// \r
+// Returns true if any component of x is true.\r
+// \r
+\r
+bool any (bvec2 x) {\r
+ return x.x || x.y;\r
+}\r
+bool any (bvec3 x) {\r
+ return x.x || x.y || x.z;\r
+}\r
+bool any (bvec4 x) {\r
+ return x.x || x.y || x.z || x.w;\r
+}\r
+\r
+// \r
+// Returns true only if all components of x are true.\r
+// \r
+\r
+bool all (bvec2 x) {\r
+ return x.x && x.y;\r
+}\r
+bool all (bvec3 x) {\r
+ return x.x && x.y && x.z;\r
+}\r
+bool all (bvec4 x) {\r
+ return x.x && x.y && x.z && x.w;\r
+}\r
+\r
+// \r
+// Returns the component-wise logical complement of x.\r
+// \r
+\r
+bvec2 not (bvec2 x) {\r
+ return bvec2 (!x.x, !x.y);\r
+}\r
+bvec3 not (bvec3 x) {\r
+ return bvec3 (!x.x, !x.y, !x.z);\r
+}\r
+bvec4 not (bvec4 x) {\r
+ return bvec4 (!x.x, !x.y, !x.z, !x.w);\r
+}\r
+\r
+// \r
+// Texture Lookup Functions\r
+// \r
+// Texture lookup functions are available to both vertex and fragment shaders. However, level\r
+// of detail is not computed by fixed functionality for vertex shaders, so there are some\r
+// differences in operation between vertex and fragment texture lookups. The functions in the table\r
+// below provide access to textures through samplers, as set up through the OpenGL API. Texture\r
+// properties such as size, pixel format, number of dimensions, filtering method, number of mip-map\r
+// levels, depth comparison, and so on are also defined by OpenGL API calls. Such properties are\r
+// taken into account as the texture is accessed via the built-in functions defined below.\r
+// \r
+// If a non-shadow texture call is made to a sampler whose texture has depth comparisons enabled,\r
+// then results are undefined. If a shadow texture call is made to a sampler whose texture does not\r
+// have depth comparisions enabled, the results are also undefined.\r
+// \r
+// In all functions below, the bias parameter is optional for fragment shaders. The bias parameter\r
+// is not accepted in a vertex shader. For a fragment shader, if bias is present, it is added to\r
+// the calculated level of detail prior to performing the texture access operation. If the bias\r
+// parameter is not provided, then the implementation automatically selects level of detail:\r
+// For a texture that is not mip-mapped, the texture is used directly. If it is mip-mapped and\r
+// running in a fragment shader, the LOD computed by the implementation is used to do the texture\r
+// lookup. If it is mip-mapped and running on the vertex shader, then the base texture is used.\r
+// \r
+// The built-ins suffixed with \93Lod\94 are allowed only in a vertex shader. For the \93Lod\94 functions,\r
+// lod is directly used as the level of detail.\r
+// \r
+\r
+// \r
+// Use the texture coordinate coord to do a texture lookup in the 1D texture currently bound\r
+// to sampler. For the projective (\93Proj\94) versions, the texture coordinate coord.s is divided by\r
+// the last component of coord.\r
+// \r
+// XXX\r
+vec4 texture1D (sampler1D sampler, float coord) {\r
+ return vec4 (0.0);\r
+}\r
+vec4 texture1DProj (sampler1D sampler, vec2 coord) {\r
+ return texture1D (sampler, coord.s / coord.t);\r
+}\r
+vec4 texture1DProj (sampler1D sampler, vec4 coord) {\r
+ return texture1D (sampler, coord.s / coord.q);\r
+}\r
+\r
+// \r
+// Use the texture coordinate coord to do a texture lookup in the 2D texture currently bound\r
+// to sampler. For the projective (\93Proj\94) versions, the texture coordinate (coord.s, coord.t) is\r
+// divided by the last component of coord. The third component of coord is ignored for the vec4\r
+// coord variant.\r
+// \r
+// XXX\r
+vec4 texture2D (sampler2D sampler, vec2 coord) {\r
+ return vec4 (0.0);\r
+}\r
+vec4 texture2DProj (sampler2D sampler, vec3 coord) {\r
+ return texture2D (sampler, vec2 (coord.s / coord.p, coord.t / coord.p));\r
+}\r
+vec4 texture2DProj (sampler2D sampler, vec4 coord) {\r
+ return texture2D (sampler, vec2 (coord.s / coord.q, coord.t / coord.q));\r
+}\r
+\r
+// \r
+// Use the texture coordinate coord to do a texture lookup in the 3D texture currently bound\r
+// to sampler. For the projective (\93Proj\94) versions, the texture coordinate is divided by coord.q.\r
+// \r
+// XXX\r
+vec4 texture3D (sampler3D sampler, vec3 coord) {\r
+ return vec4 (0.0);\r
+}\r
+vec4 texture3DProj (sampler3D sampler, vec4 coord) {\r
+ return texture3D (sampler, vec3 (coord.s / coord.q, coord.t / coord.q, coord.p / coord.q));\r
+}\r
+\r
+// \r
+// Use the texture coordinate coord to do a texture lookup in the cube map texture currently bound\r
+// to sampler. The direction of coord is used to select which face to do a 2-dimensional texture\r
+// lookup in, as described in section 3.8.6 in version 1.4 of the OpenGL specification.\r
+// \r
+// XXX\r
+vec4 textureCube (samplerCube sampler, vec3 coord) {\r
+ return vec4 (0.0);\r
+}\r
+\r
+// \r
+// Use texture coordinate coord to do a depth comparison lookup on the depth texture bound\r
+// to sampler, as described in section 3.8.14 of version 1.4 of the OpenGL specification. The 3rd\r
+// component of coord (coord.p) is used as the R value. The texture bound to sampler must be a\r
+// depth texture, or results are undefined. For the projective (\93Proj\94) version of each built-in,\r
+// the texture coordinate is divide by coord.q, giving a depth value R of coord.p/coord.q. The\r
+// second component of coord is ignored for the \931D\94 variants.\r
+// \r
+// XXX\r
+vec4 shadow1D (sampler1DShadow sampler, vec3 coord) {\r
+ return vec4 (0.0);\r
+}\r
+// XXX\r
+vec4 shadow2D (sampler2DShadow sampler, vec3 coord) {\r
+ return vec4 (0.0);\r
+}\r
+vec4 shadow1DProj (sampler1DShadow sampler, vec4 coord) {\r
+ return shadow1D (sampler, vec3 (coord.s / coord.q, 0.0, coord.p / coord.q));\r
+}\r
+vec4 shadow2DProj (sampler2DShadow sampler, vec4 coord) {\r
+ return shadow2D (sampler, vec3 (coord.s / coord.q, coord.t / coord.q, coord.p / coord.q));\r
+}\r
+\r
+// \r
+// Noise Functions\r
+// \r
+// Noise functions are available to both fragment and vertex shaders. They are stochastic functions\r
+// that can be used to increase visual complexity. Values returned by the following noise functions\r
+// give the appearance of randomness, but are not truly random. The noise functions below are\r
+// defined to have the following characteristics:\r
+// \r
+// \95 The return value(s) are always in the range [-1,1]\r
+// \95 The return value(s) have an overall average of 0.0\r
+// \95 They are repeatable, in that a particular input value will always produce the same return value\r
+// \95 They are statistically invariant under rotation (i.e., no matter how the domain is rotated, it\r
+// has the same statistical character)\r
+// \95 They have a statistical invariance under translation (i.e., no matter how the domain is\r
+// translated, it has the same statistical character)\r
+// \95 They typically give different results under translation.\r
+// \95 They have a narrow bandpass limit in frequency (i.e., it has no visible features larger or\r
+// smaller than a certain narrow size range)\r
+// \r
+\r
+// \r
+// Returns a 1D noise value based on the input value x.\r
+// \r
+// XXX\r
+float noise1 (float x) {\r
+ return 0.0;\r
+}\r
+// XXX\r
+float noise1 (vec2 x) {\r
+ return 0.0;\r
+}\r
+// XXX\r
+float noise1 (vec3 x) {\r
+ return 0.0;\r
+}\r
+// XXX\r
+float noise1 (vec4 x) {\r
+ return 0.0;\r
+}\r
+\r
+// \r
+// Returns a 2D noise value based on the input value x.\r
+// \r
+// XXX\r
+vec2 noise2 (float x) {\r
+ return vec2 (0.0);\r
+}\r
+// XXX\r
+vec2 noise2 (vec2 x) {\r
+ return vec2 (0.0);\r
+}\r
+// XXX\r
+vec2 noise2 (vec3 x) {\r
+ return vec2 (0.0);\r
+}\r
+// XXX\r
+vec2 noise2 (vec4 x) {\r
+ return vec2 (0.0);\r
+}\r
+\r
+// \r
+// Returns a 3D noise value based on the input value x.\r
+// \r
+// XXX\r
+vec3 noise3 (float x) {\r
+ return vec3 (0.0);\r
+}\r
+// XXX\r
+vec3 noise3 (vec2 x) {\r
+ return vec3 (0.0);\r
+}\r
+// XXX\r
+vec3 noise3 (vec3 x) {\r
+ return vec3 (0.0);\r
+}\r
+// XXX\r
+vec3 noise3 (vec4 x) {\r
+ return vec3 (0.0);\r
+}\r
+\r
+// \r
+// Returns a 4D noise value based on the input value x.\r
+// \r
+// XXX\r
+vec4 noise4 (float x) {\r
+ return vec4 (0.0);\r
+}\r
+// XXX\r
+vec4 noise4 (vec2 x) {\r
+ return vec4 (0.0);\r
+}\r
+// XXX\r
+vec4 noise4 (vec3 x) {\r
+ return vec4 (0.0);\r
+}\r
+// XXX\r
+vec4 noise4 (vec4 x) {\r
+ return vec4 (0.0);\r
+}\r
+\r
--- /dev/null
+\r
+// \r
+// TODO:\r
+// - implement texture1D, texture2D, texture3D, textureCube,\r
+// - implement shadow1D, shadow2D,\r
+// - implement dFdx, dFdy,\r
+// \r
+\r
+// \r
+// From Shader Spec, ver. 1.051\r
+// \r
+// The output of the fragment shader goes on to be processed by the fixed function operations at\r
+// the back end of the OpenGL pipeline. Fragment shaders interface with the back end of the OpenGL\r
+// pipeline using the built-in variables gl_FragColor and gl_FragDepth, or by executing the discard\r
+// keyword.\r
+// \r
+// These variables may be written more than once within a fragment shader. If so, the last value\r
+// assigned is the one used in the subsequent fixed function pipeline. The values written to these\r
+// variables may be read back after writing them. Reading from these variables before writing them\r
+// results in an undefined value. The fixed functionality computed depth for a fragment may be\r
+// obtained by reading gl_FragCoord.z, described below.\r
+// \r
+// Writing to gl_FragColor specifies the fragment color that will be used by the subsequent fixed\r
+// functionality pipeline. If subsequent fixed functionality consumes fragment color and an\r
+// execution of a fragment shader does not write a value to gl_FragColor then the fragment color\r
+// consumed is undefined.\r
+// \r
+// If the frame buffer is configured as a color index buffer then behavior is undefined when using\r
+// a fragment shader.\r
+// \r
+// Writing to gl_FragDepth will establish the depth value for the fragment being processed. If\r
+// depth buffering is enabled, and a shader does not write gl_FragDepth, then the fixed function\r
+// value for depth will be used as the fragment\92s depth value. If a shader statically assigns\r
+// a value to gl_FragDepth, and there is an execution path through the shader that does not set\r
+// gl_FragDepth, then the value of the fragment\92s depth may be undefined for some executions of\r
+// the shader. That is, if a shader statically writes gl_FragDepth, then it is responsible for\r
+// always writing it. There is also no guarantee that a shader can compute the same depth value\r
+// as the fixed function value; an implementation will provide invariant results within shaders\r
+// computing depth with the same source-level expression, but invariance is not provided between\r
+// shaders and fixed functionality.\r
+// \r
+// Writes to gl_FragColor and gl_FragDepth need not be clamped within a shader. The fixed\r
+// functionality pipeline following the fragment shader will clamp these values.\r
+// \r
+// If a shader executes the discard keyword, the fragment is discarded, and the values of\r
+// gl_FragDepth and gl_FragColor become irrelevant.\r
+// \r
+// The variable gl_FragCoord is available as a read-only variable from within fragment shaders\r
+// and it holds the window relative coordinates x, y, z, and 1/w values for the fragment. This\r
+// value is the result of the fixed functionality that interpolates primitives after vertex\r
+// processing to generate fragments. The z component is the depth value that would be used for\r
+// the fragment\92s depth if a shader contained no writes to gl_FragDepth. This is useful for\r
+// invariance if a shader conditionally computes gl_FragDepth but otherwise wants the fixed\r
+// functionality fragment depth.\r
+// \r
+// The fragment shader has access to the read-only built-in variable gl_FrontFacing whose value\r
+// is true if the fragment belongs to a front-facing primitive. One use of this is to emulate\r
+// two-sided lighting by selecting one of two colors calculated by the vertex shader.\r
+// \r
+// The built-in variables that are accessible from a fragment shader are intrinsically given types\r
+// as follows:\r
+// \r
+\r
+vec4 gl_FragCoord;\r
+bool gl_FrontFacing;\r
+vec4 gl_FragColor;\r
+float gl_FragDepth;\r
+\r
+// \r
+// However, they do not behave like variables with no qualifier; their behavior is as described\r
+// above. These built-in variables have global scope.\r
+// \r
+\r
+// \r
+// Unlike user-defined varying variables, the built-in varying variables don\92t have a strict\r
+// one-to-one correspondence between the vertex language and the fragment language. Two sets are\r
+// provided, one for each language. Their relationship is described below.\r
+// \r
+// The following varying variables are available to read from in a fragment shader. The gl_Color\r
+// and gl_SecondaryColor names are the same names as attributes passed to the vertex shader.\r
+// However, there is no name conflict, because attributes are visible only in vertex shaders\r
+// and the following are only visible in a fragment shader.\r
+// \r
+\r
+varying vec4 gl_Color;\r
+varying vec4 gl_SecondaryColor;\r
+varying vec4 gl_TexCoord[]; // at most will be gl_MaxTextureCoordsARB\r
+varying float gl_FogFragCoord;\r
+\r
+// \r
+// The values in gl_Color and gl_SecondaryColor will be derived automatically by the system from\r
+// gl_FrontColor, gl_BackColor, gl_FrontSecondaryColor, and gl_BackSecondaryColor based on which\r
+// face is visible. If fixed functionality is used for vertex processing, then gl_FogFragCoord will\r
+// either be the z-coordinate of the fragment in eye space, or the interpolation of the fog\r
+// coordinate, as described in section 3.10 of the OpenGL 1.4 Specification. The gl_TexCoord[]\r
+// values are the interpolated gl_TexCoord[] values from a vertex shader or the texture coordinates\r
+// of any fixed pipeline based vertex functionality.\r
+// \r
+// Indices to the fragment shader gl_TexCoord array are as described above in the vertex shader\r
+// text.\r
+// \r
+\r
+// \r
+// The OpenGL Shading Language defines an assortment of built-in convenience functions for scalar\r
+// and vector operations. Many of these built-in functions can be used in more than one type\r
+// of shader, but some are intended to provide a direct mapping to hardware and so are available\r
+// only for a specific type of shader.\r
+// \r
+// The built-in functions basically fall into three categories:\r
+// \r
+// \95 They expose some necessary hardware functionality in a convenient way such as accessing\r
+// a texture map. There is no way in the language for these functions to be emulated by a shader.\r
+// \r
+// \95 They represent a trivial operation (clamp, mix, etc.) that is very simple for the user\r
+// to write, but they are very common and may have direct hardware support. It is a very hard\r
+// problem for the compiler to map expressions to complex assembler instructions.\r
+// \r
+// \95 They represent an operation graphics hardware is likely to accelerate at some point. The\r
+// trigonometry functions fall into this category.\r
+// \r
+// Many of the functions are similar to the same named ones in common C libraries, but they support\r
+// vector input as well as the more traditional scalar input.\r
+// \r
+// Applications should be encouraged to use the built-in functions rather than do the equivalent\r
+// computations in their own shader code since the built-in functions are assumed to be optimal\r
+// (e.g., perhaps supported directly in hardware).\r
+// \r
+// User code can replace built-in functions with their own if they choose, by simply re-declaring\r
+// and defining the same name and argument list.\r
+// \r
+\r
+// \r
+// Texture Lookup Functions\r
+// \r
+// Texture lookup functions are available to both vertex and fragment shaders. However, level\r
+// of detail is not computed by fixed functionality for vertex shaders, so there are some\r
+// differences in operation between vertex and fragment texture lookups. The functions in the table\r
+// below provide access to textures through samplers, as set up through the OpenGL API. Texture\r
+// properties such as size, pixel format, number of dimensions, filtering method, number of mip-map\r
+// levels, depth comparison, and so on are also defined by OpenGL API calls. Such properties are\r
+// taken into account as the texture is accessed via the built-in functions defined below.\r
+// \r
+// If a non-shadow texture call is made to a sampler whose texture has depth comparisons enabled,\r
+// then results are undefined. If a shadow texture call is made to a sampler whose texture does not\r
+// have depth comparisions enabled, the results are also undefined.\r
+// \r
+// In all functions below, the bias parameter is optional for fragment shaders. The bias parameter\r
+// is not accepted in a vertex shader. For a fragment shader, if bias is present, it is added to\r
+// the calculated level of detail prior to performing the texture access operation. If the bias\r
+// parameter is not provided, then the implementation automatically selects level of detail:\r
+// For a texture that is not mip-mapped, the texture is used directly. If it is mip-mapped and\r
+// running in a fragment shader, the LOD computed by the implementation is used to do the texture\r
+// lookup. If it is mip-mapped and running on the vertex shader, then the base texture is used.\r
+// \r
+// The built-ins suffixed with \93Lod\94 are allowed only in a vertex shader. For the \93Lod\94 functions,\r
+// lod is directly used as the level of detail.\r
+// \r
+\r
+// \r
+// Use the texture coordinate coord to do a texture lookup in the 1D texture currently bound\r
+// to sampler. For the projective (\93Proj\94) versions, the texture coordinate coord.s is divided by\r
+// the last component of coord.\r
+// \r
+// XXX\r
+vec4 texture1D (sampler1D sampler, float coord, float bias) {\r
+ return vec4 (0.0);\r
+}\r
+vec4 texture1DProj (sampler1D sampler, vec2 coord, float bias) {\r
+ return texture1D (sampler, coord.s / coord.t, bias);\r
+}\r
+vec4 texture1DProj (sampler1D sampler, vec4 coord, float bias) {\r
+ return texture1D (sampler, coord.s / coord.q, bias);\r
+}\r
+\r
+// \r
+// Use the texture coordinate coord to do a texture lookup in the 2D texture currently bound\r
+// to sampler. For the projective (\93Proj\94) versions, the texture coordinate (coord.s, coord.t) is\r
+// divided by the last component of coord. The third component of coord is ignored for the vec4\r
+// coord variant.\r
+// \r
+// XXX\r
+vec4 texture2D (sampler2D sampler, vec2 coord, float bias) {\r
+ return vec4 (0.0);\r
+}\r
+vec4 texture2DProj (sampler2D sampler, vec3 coord, float bias) {\r
+ return texture2D (sampler, vec2 (coord.s / coord.p, coord.t / coord.p), bias);\r
+}\r
+vec4 texture2DProj (sampler2D sampler, vec4 coord, float bias) {\r
+ return texture2D (sampler, vec2 (coord.s / coord.q, coord.s / coord.q), bias);\r
+}\r
+\r
+// \r
+// Use the texture coordinate coord to do a texture lookup in the 3D texture currently bound\r
+// to sampler. For the projective (\93Proj\94) versions, the texture coordinate is divided by coord.q.\r
+// \r
+// XXX\r
+vec4 texture3D (sampler3D sampler, vec3 coord, float bias) {\r
+ return vec4 (0.0);\r
+} \r
+vec4 texture3DProj (sampler3D sampler, vec4 coord, float bias) {\r
+ return texture3DProj (sampler, vec3 (coord.s / coord.q, coord.t / coord.q, coord.p / coord.q),\r
+ bias);\r
+}\r
+\r
+// \r
+// Use the texture coordinate coord to do a texture lookup in the cube map texture currently bound\r
+// to sampler. The direction of coord is used to select which face to do a 2-dimensional texture\r
+// lookup in, as described in section 3.8.6 in version 1.4 of the OpenGL specification.\r
+// \r
+// XXX\r
+vec4 textureCube (samplerCube sampler, vec3 coord, float bias) {\r
+ return vec4 (0.0);\r
+}\r
+\r
+// \r
+// Use texture coordinate coord to do a depth comparison lookup on the depth texture bound\r
+// to sampler, as described in section 3.8.14 of version 1.4 of the OpenGL specification. The 3rd\r
+// component of coord (coord.p) is used as the R value. The texture bound to sampler must be a\r
+// depth texture, or results are undefined. For the projective (\93Proj\94) version of each built-in,\r
+// the texture coordinate is divide by coord.q, giving a depth value R of coord.p/coord.q. The\r
+// second component of coord is ignored for the \931D\94 variants.\r
+// \r
+// XXX\r
+vec4 shadow1D (sampler1DShadow sampler, vec3 coord, float bias) {\r
+ return vec4 (0.0);\r
+}\r
+// XXX\r
+vec4 shadow2D (sampler2DShadow sampler, vec3 coord, float bias) {\r
+ return vec4 (0.0);\r
+}\r
+vec4 shadow1DProj (sampler1DShadow sampler, vec4 coord, float bias) {\r
+ return shadow1D (sampler, vec3 (coord.s / coord.q, 0.0, coord.p / coord.q), bias);\r
+}\r
+vec4 shadow2DProj (sampler2DShadow sampler, vec4 coord, float bias) {\r
+ return shadow2D (sampler, vec3 (coord.s / coord.q, coord.t / coord.q, coord.p / coord.q), bias);\r
+}\r
+\r
+// \r
+// Fragment processing functions are only available in shaders intended for use on the fragment\r
+// processor. Derivatives may be computationally expensive and/or numerically unstable. Therefore,\r
+// an OpenGL implementation may approximate the true derivatives by using a fast but not entirely\r
+// accurate derivative computation.\r
+// \r
+// The expected behavior of a derivative is specified using forward/backward differencing.\r
+// \r
+// Forward differencing:\r
+// \r
+// F(x+dx) - F(x) ~ dFdx(x) * dx 1a\r
+// dFdx(x) ~ (F(x+dx) - F(x)) / dx 1b\r
+// \r
+// Backward differencing:\r
+// \r
+// F(x-dx) - F(x) ~ -dFdx(x) * dx 2a\r
+// dFdx(x) ~ (F(x) - F(x-dx)) / dx 2b\r
+// \r
+// With single-sample rasterization, dx <= 1.0 in equations 1b and 2b. For multi-sample\r
+// rasterization, dx < 2.0 in equations 1b and 2b.\r
+// \r
+// dFdy is approximated similarly, with y replacing x.\r
+// \r
+// A GL implementation may use the above or other methods to perform the calculation, subject\r
+// to the following conditions:\r
+// \r
+// 1) The method may use piecewise linear approximations. Such linear approximations imply that\r
+// higher order derivatives, dFdx(dFdx(x)) and above, are undefined.\r
+// \r
+// 2) The method may assume that the function evaluated is continuous. Therefore derivatives within\r
+// the body of a non-uniform conditional are undefined.\r
+// \r
+// 3) The method may differ per fragment, subject to the constraint that the method may vary by\r
+// window coordinates, not screen coordinates. The invariance requirement described in section\r
+// 3.1 of the OpenGL 1.4 specification is relaxed for derivative calculations, because\r
+// the method may be a function of fragment location.\r
+// \r
+// Other properties that are desirable, but not required, are:\r
+// \r
+// 4) Functions should be evaluated within the interior of a primitive (interpolated, not\r
+// extrapolated).\r
+// \r
+// 5) Functions for dFdx should be evaluated while holding y constant. Functions for dFdy should\r
+// be evaluated while holding x constant. However, mixed higher order derivatives, like\r
+// dFdx(dFdy(y)) and dFdy(dFdx(x)) are undefined.\r
+// \r
+// In some implementations, varying degrees of derivative accuracy may be obtained by providing\r
+// GL hints (section 5.6 of the OpenGL 1.4 specification), allowing a user to make an image\r
+// quality versus speed tradeoff.\r
+// \r
+\r
+// \r
+// Returns the derivative in x using local differencing for the input argument p.\r
+// \r
+// XXX\r
+float dFdx (float p) {\r
+ return 0.0;\r
+}\r
+// XXX\r
+vec2 dFdx (vec2 p) {\r
+ return vec2 (0.0);\r
+}\r
+// XXX\r
+vec3 dFdx (vec3 p) {\r
+ return vec3 (0.0);\r
+}\r
+// XXX\r
+vec4 dFdx (vec4 p) {\r
+ return vec4 (0.0);\r
+}\r
+\r
+// \r
+// Returns the derivative in y using local differencing for the input argument p.\r
+// \r
+// These two functions are commonly used to estimate the filter width used to anti-alias procedural\r
+// textures.We are assuming that the expression is being evaluated in parallel on a SIMD array so\r
+// that at any given point in time the value of the function is known at the grid points\r
+// represented by the SIMD array. Local differencing between SIMD array elements can therefore\r
+// be used to derive dFdx, dFdy, etc.\r
+// \r
+// XXX\r
+float dFdy (float p) {\r
+ return 0.0;\r
+}\r
+// XXX\r
+vec2 dFdy (vec2 p) {\r
+ return vec2 (0.0);\r
+}\r
+// XXX\r
+vec3 dFdy (vec3 p) {\r
+ return vec3 (0.0);\r
+}\r
+// XXX\r
+vec4 dFdy (vec4 p) {\r
+ return vec4 (0.0);\r
+}\r
+\r
+// \r
+// Returns the sum of the absolute derivative in x and y using local differencing for the input\r
+// argument p, i.e.:\r
+// \r
+// return = abs (dFdx (p)) + abs (dFdy (p));\r
+// \r
+\r
+float fwidth (float p) {\r
+ return abs (dFdx (p)) + abs (dFdy (p));\r
+}\r
+vec2 fwidth (vec2 p) {\r
+ return abs (dFdx (p)) + abs (dFdy (p));\r
+}\r
+vec3 fwidth (vec3 p) {\r
+ return abs (dFdx (p)) + abs (dFdy (p));\r
+}\r
+vec4 fwidth (vec4 p) {\r
+ return abs (dFdx (p)) + abs (dFdy (p));\r
+}\r
+\r
--- /dev/null
+\r
+// \r
+// TODO:\r
+// - what to do with ftransform? can it stay in the current form?\r
+// - implement texture1DLod, texture2DLod, texture3DLod, textureCubeLod,\r
+// - implement shadow1DLod, shadow2DLod,\r
+// \r
+\r
+// \r
+// From Shader Spec, ver. 1.051\r
+// \r
+// Some OpenGL operations still continue to occur in fixed functionality in between the vertex\r
+// processor and the fragment processor. Other OpenGL operations continue to occur in fixed\r
+// functionality after the fragment processor. Shaders communicate with the fixed functionality\r
+// of OpenGL through the use of built-in variables.\r
+// \r
+// The variable gl_Position is available only in the vertex language and is intended for writing\r
+// the homogeneous vertex position. All executions of a well-formed vertex shader must write\r
+// a value into this variable. It can be written at any time during shader execution. It may also\r
+// be read back by the shader after being written. This value will be used by primitive assembly,\r
+// clipping, culling, and other fixed functionality operations that operate on primitives after\r
+// vertex processing has occurred. Compilers may generate a diagnostic message if they detect\r
+// gl_Position is not written, or read before being written, but not all such cases are detectable.\r
+// Results are undefined if a vertex shader is executed and does not write gl_Position.\r
+// \r
+// The variable gl_PointSize is available only in the vertex language and is intended for a vertex\r
+// shader to write the size of the point to be rasterized. It is measured in pixels.\r
+// \r
+// The variable gl_ClipVertex is available only in the vertex language and provides a place for\r
+// vertex shaders to write the coordinate to be used with the user clipping planes. The user must\r
+// ensure the clip vertex and user clipping planes are defined in the same coordinate space. User\r
+// clip planes work properly only under linear transform. It is undefined what happens under\r
+// non-linear transform.\r
+// \r
+// These built-in vertex shader variables for communicating with fixed functionality are\r
+// intrinsically declared with the following types:\r
+// \r
+\r
+vec4 gl_Position; // must be written to\r
+float gl_PointSize; // may be written to\r
+vec4 gl_ClipVertex; // may be written to\r
+\r
+// \r
+// If gl_PointSize or gl_ClipVertex are not written to, their values are undefined. Any of these\r
+// variables can be read back by the shader after writing to them, to retrieve what was written.\r
+// Reading them before writing them results in undefined behavior. If they are written more than\r
+// once, it is the last value written that is consumed by the subsequent operations.\r
+// \r
+// These built-in variables have global scope.\r
+// \r
+\r
+// \r
+// The following attribute names are built into the OpenGL vertex language and can be used from\r
+// within a vertex shader to access the current values of attributes declared by OpenGL. All page\r
+// numbers and notations are references to the OpenGL 1.4 specification.\r
+// \r
+\r
+// \r
+// Vertex Attributes, p. 19.\r
+// \r
+\r
+attribute vec4 gl_Color;\r
+attribute vec4 gl_SecondaryColor;\r
+attribute vec3 gl_Normal;\r
+attribute vec4 gl_Vertex;\r
+attribute vec4 gl_MultiTexCoord0;\r
+attribute vec4 gl_MultiTexCoord1;\r
+attribute vec4 gl_MultiTexCoord2;\r
+attribute vec4 gl_MultiTexCoord3;\r
+attribute vec4 gl_MultiTexCoord4;\r
+attribute vec4 gl_MultiTexCoord5;\r
+attribute vec4 gl_MultiTexCoord6;\r
+attribute vec4 gl_MultiTexCoord7;\r
+attribute float gl_FogCoord;\r
+\r
+// \r
+// Unlike user-defined varying variables, the built-in varying variables don\92t have a strict\r
+// one-to-one correspondence between the vertex language and the fragment language. Two sets are\r
+// provided, one for each language. Their relationship is described below.\r
+// \r
+// The following built-in varying variables are available to write to in a vertex shader.\r
+// A particular one should be written to if any functionality in a corresponding fragment shader\r
+// or fixed pipeline uses it or state derived from it. Otherwise, behavior is undefined.\r
+//\r
+\r
+varying vec4 gl_FrontColor;\r
+varying vec4 gl_BackColor;\r
+varying vec4 gl_FrontSecondaryColor;\r
+varying vec4 gl_BackSecondaryColor;\r
+varying vec4 gl_TexCoord[]; // at most will be gl_MaxTextureCoordsARB\r
+varying float gl_FogFragCoord;\r
+\r
+// \r
+// For gl_FogFragCoord, the value written will be used as the \93c\94 value on page 160 of the\r
+// OpenGL 1.4 Specification by the fixed functionality pipeline. For example, if the z-coordinate\r
+// of the fragment in eye space is desired as \93c\94, then that's what the vertex shader should write\r
+// into gl_FogFragCoord.\r
+// \r
+// As with all arrays, indices used to subscript gl_TexCoord must either be integral constant\r
+// expressions, or this array must be re-declared by the shader with a size. The size can be\r
+// at most gl_MaxTextureCoordsARB. Using indexes close to 0 may aid the implementation\r
+// in preserving varying resources.\r
+// \r
+\r
+// \r
+// The OpenGL Shading Language defines an assortment of built-in convenience functions for scalar\r
+// and vector operations. Many of these built-in functions can be used in more than one type\r
+// of shader, but some are intended to provide a direct mapping to hardware and so are available\r
+// only for a specific type of shader.\r
+// \r
+// The built-in functions basically fall into three categories:\r
+// \r
+// \95 They expose some necessary hardware functionality in a convenient way such as accessing\r
+// a texture map. There is no way in the language for these functions to be emulated by a shader.\r
+// \r
+// \95 They represent a trivial operation (clamp, mix, etc.) that is very simple for the user\r
+// to write, but they are very common and may have direct hardware support. It is a very hard\r
+// problem for the compiler to map expressions to complex assembler instructions.\r
+// \r
+// \95 They represent an operation graphics hardware is likely to accelerate at some point. The\r
+// trigonometry functions fall into this category.\r
+// \r
+// Many of the functions are similar to the same named ones in common C libraries, but they support\r
+// vector input as well as the more traditional scalar input.\r
+// \r
+// Applications should be encouraged to use the built-in functions rather than do the equivalent\r
+// computations in their own shader code since the built-in functions are assumed to be optimal\r
+// (e.g., perhaps supported directly in hardware).\r
+// \r
+// User code can replace built-in functions with their own if they choose, by simply re-declaring\r
+// and defining the same name and argument list.\r
+// \r
+\r
+// \r
+// Geometric Functions\r
+// \r
+// These operate on vectors as vectors, not component-wise.\r
+// \r
+\r
+// \r
+// For vertex shaders only. This function will ensure that the incoming vertex value will be\r
+// transformed in a way that produces exactly the same result as would be produced by OpenGL\92s\r
+// fixed functionality transform. It is intended to be used to compute gl_Position, e.g.,\r
+// gl_Position = ftransform()\r
+// This function should be used, for example, when an application is rendering the same geometry in\r
+// separate passes, and one pass uses the fixed functionality path to render and another pass uses\r
+// programmable shaders.\r
+// \r
+\r
+vec4 ftransform () {\r
+ return gl_ModelViewProjectionMatrix * gl_Vertex;\r
+}\r
+\r
+// \r
+// Texture Lookup Functions\r
+// \r
+// Texture lookup functions are available to both vertex and fragment shaders. However, level\r
+// of detail is not computed by fixed functionality for vertex shaders, so there are some\r
+// differences in operation between vertex and fragment texture lookups. The functions in the table\r
+// below provide access to textures through samplers, as set up through the OpenGL API. Texture\r
+// properties such as size, pixel format, number of dimensions, filtering method, number of mip-map\r
+// levels, depth comparison, and so on are also defined by OpenGL API calls. Such properties are\r
+// taken into account as the texture is accessed via the built-in functions defined below.\r
+// \r
+// If a non-shadow texture call is made to a sampler whose texture has depth comparisons enabled,\r
+// then results are undefined. If a shadow texture call is made to a sampler whose texture does not\r
+// have depth comparisions enabled, the results are also undefined.\r
+// \r
+// In all functions below, the bias parameter is optional for fragment shaders. The bias parameter\r
+// is not accepted in a vertex shader. For a fragment shader, if bias is present, it is added to\r
+// the calculated level of detail prior to performing the texture access operation. If the bias\r
+// parameter is not provided, then the implementation automatically selects level of detail:\r
+// For a texture that is not mip-mapped, the texture is used directly. If it is mip-mapped and\r
+// running in a fragment shader, the LOD computed by the implementation is used to do the texture\r
+// lookup. If it is mip-mapped and running on the vertex shader, then the base texture is used.\r
+// \r
+// The built-ins suffixed with \93Lod\94 are allowed only in a vertex shader. For the \93Lod\94 functions,\r
+// lod is directly used as the level of detail.\r
+// \r
+\r
+// \r
+// Use the texture coordinate coord to do a texture lookup in the 1D texture currently bound\r
+// to sampler. For the projective (\93Proj\94) versions, the texture coordinate coord.s is divided by\r
+// the last component of coord.\r
+// \r
+// XXX\r
+vec4 texture1DLod (sampler1D sampler, float coord, float lod) {\r
+ return vec4 (0.0);\r
+}\r
+vec4 texture1DProjLod (sampler1D sampler, vec2 coord, float lod) {\r
+ return texture1DLod (sampler, coord.s / coord.t, lod);\r
+}\r
+vec4 texture1DProjLod (sampler1D sampler, vec4 coord, float lod) {\r
+ return texture1DLod (sampler, coord.s / coord.q, lod);\r
+}\r
+\r
+// \r
+// Use the texture coordinate coord to do a texture lookup in the 2D texture currently bound\r
+// to sampler. For the projective (\93Proj\94) versions, the texture coordinate (coord.s, coord.t) is\r
+// divided by the last component of coord. The third component of coord is ignored for the vec4\r
+// coord variant.\r
+// \r
+// XXX\r
+vec4 texture2DLod (sampler2D sampler, vec2 coord, float lod) {\r
+ return vec4 (0.0);\r
+}\r
+vec4 texture2DProjLod (sampler2D sampler, vec3 coord, float lod) {\r
+ return texture2DLod (sampler, vec2 (coord.s / coord.p, coord.t / coord.p), lod);\r
+}\r
+vec4 texture2DProjLod (sampler2D sampler, vec4 coord, float lod) {\r
+ return texture2DLod (sampler, vec2 (coord.s / coord.q, coord.t / coord.q), lod);\r
+}\r
+\r
+// \r
+// Use the texture coordinate coord to do a texture lookup in the 3D texture currently bound\r
+// to sampler. For the projective (\93Proj\94) versions, the texture coordinate is divided by coord.q.\r
+// \r
+// XXX\r
+vec4 texture3DLod (sampler3D sampler, vec3 coord, float lod) {\r
+ return vec4 (0.0);\r
+}\r
+vec4 texture3DProjLod (sampler3D sampler, vec4 coord, float lod) {\r
+ return texture3DLod (sampler, vec3 (coord.s / coord.q, coord.t / coord.q, coord.s / coord.q),\r
+ lod);\r
+}\r
+\r
+// \r
+// Use the texture coordinate coord to do a texture lookup in the cube map texture currently bound\r
+// to sampler. The direction of coord is used to select which face to do a 2-dimensional texture\r
+// lookup in, as described in section 3.8.6 in version 1.4 of the OpenGL specification.\r
+// \r
+// XXX\r
+vec4 textureCubeLod (samplerCube sampler, vec3 coord, float lod) {\r
+ return vec4 (0.0);\r
+}\r
+\r
+// \r
+// Use texture coordinate coord to do a depth comparison lookup on the depth texture bound\r
+// to sampler, as described in section 3.8.14 of version 1.4 of the OpenGL specification. The 3rd\r
+// component of coord (coord.p) is used as the R value. The texture bound to sampler must be a\r
+// depth texture, or results are undefined. For the projective (\93Proj\94) version of each built-in,\r
+// the texture coordinate is divide by coord.q, giving a depth value R of coord.p/coord.q. The\r
+// second component of coord is ignored for the \931D\94 variants.\r
+// \r
+// XXX\r
+vec4 shadow1DLod (sampler1DShadow sampler, vec3 coord, float lod) {\r
+ return vec4 (0.0);\r
+}\r
+// XXX\r
+vec4 shadow2DLod (sampler2DShadow sampler, vec3 coord, float lod) {\r
+ return vec4 (0.0);\r
+}\r
+vec4 shadow1DProjLod(sampler1DShadow sampler, vec4 coord, float lod) {\r
+ return shadow1DLod (sampler, vec3 (coord.s / coord.q, 0.0, coord.p / coord.q), lod);\r
+}\r
+vec4 shadow2DProjLod(sampler2DShadow sampler, vec4 coord, float lod) {\r
+ return shadow2DLod (sampler, vec3 (coord.s / coord.q, coord.t / coord.q, coord.p / coord.q),\r
+ lod);\r
+}\r
+\r
projects / mesa.git / commitdiff