2 * Procedural Bump Mapping demo. Uses the example shaders from
3 * chapter 11 of the OpenGL Shading Language "orange" book.
16 #include "shaderutil.h"
19 static char *FragProgFile
= "CH11-bumpmap.frag";
20 static char *VertProgFile
= "CH11-bumpmap.vert";
22 /* program/shader objects */
23 static GLuint fragShader
;
24 static GLuint vertShader
;
25 static GLuint program
;
28 static struct uniform_info Uniforms
[] = {
29 { "LightPosition", 3, GL_FLOAT
, { 0.57737, 0.57735, 0.57735, 0.0 }, -1 },
30 { "SurfaceColor", 3, GL_FLOAT
, { 0.8, 0.8, 0.2, 0 }, -1 },
31 { "BumpDensity", 1, GL_FLOAT
, { 10.0, 0, 0, 0 }, -1 },
32 { "BumpSize", 1, GL_FLOAT
, { 0.125, 0, 0, 0 }, -1 },
33 { "SpecularFactor", 1, GL_FLOAT
, { 0.5, 0, 0, 0 }, -1 },
39 static GLfloat xRot
= 20.0f
, yRot
= 0.0f
, zRot
= 0.0f
;
41 static GLuint tangentAttrib
;
43 static GLboolean Anim
= GL_FALSE
;
49 GLenum err
= glGetError();
51 printf("GL Error %s (0x%x) at line %d\n",
52 gluErrorString(err
), (int) err
, line
);
57 * Draw a square, specifying normal and tangent vectors.
63 glVertexAttrib3f_func(tangentAttrib
, 1, 0, 0);
65 glTexCoord2f(0, 0); glVertex2f(-size
, -size
);
66 glTexCoord2f(1, 0); glVertex2f( size
, -size
);
67 glTexCoord2f(1, 1); glVertex2f( size
, size
);
68 glTexCoord2f(0, 1); glVertex2f(-size
, size
);
78 glRotatef(90, 0, 1, 0);
79 glTranslatef(0, 0, size
);
85 glRotatef(-90, 0, 1, 0);
86 glTranslatef(0, 0, size
);
92 glRotatef(90, 1, 0, 0);
93 glTranslatef(0, 0, size
);
99 glRotatef(-90, 1, 0, 0);
100 glTranslatef(0, 0, size
);
107 glTranslatef(0, 0, size
);
113 glRotatef(180, 0, 1, 0);
114 glTranslatef(0, 0, size
);
124 GLint t
= glutGet(GLUT_ELAPSED_TIME
);
133 glClear(GL_COLOR_BUFFER_BIT
| GL_DEPTH_BUFFER_BIT
);
136 glRotatef(xRot
, 1.0f
, 0.0f
, 0.0f
);
137 glRotatef(yRot
, 0.0f
, 1.0f
, 0.0f
);
138 glRotatef(zRot
, 0.0f
, 0.0f
, 1.0f
);
144 CheckError(__LINE__
);
151 Reshape(int width
, int height
)
153 float ar
= (float) width
/ (float) height
;
154 glViewport(0, 0, width
, height
);
155 glMatrixMode(GL_PROJECTION
);
157 glFrustum(-ar
, ar
, -1.0, 1.0, 5.0, 25.0);
158 glMatrixMode(GL_MODELVIEW
);
160 glTranslatef(0.0f
, 0.0f
, -15.0f
);
167 glDeleteShader_func(fragShader
);
168 glDeleteShader_func(vertShader
);
169 glDeleteProgram_func(program
);
170 glutDestroyWindow(win
);
175 Key(unsigned char key
, int x
, int y
)
177 const GLfloat step
= 2.0;
184 glutIdleFunc(Anim
? Idle
: NULL
);
202 SpecialKey(int key
, int x
, int y
)
204 const GLfloat step
= 2.0;
230 if (!ShadersSupported())
235 vertShader
= CompileShaderFile(GL_VERTEX_SHADER
, VertProgFile
);
236 fragShader
= CompileShaderFile(GL_FRAGMENT_SHADER
, FragProgFile
);
237 program
= LinkShaders(vertShader
, fragShader
);
239 glUseProgram_func(program
);
241 assert(glIsProgram_func(program
));
242 assert(glIsShader_func(fragShader
));
243 assert(glIsShader_func(vertShader
));
245 assert(glGetError() == 0);
247 CheckError(__LINE__
);
249 InitUniforms(program
, Uniforms
);
251 CheckError(__LINE__
);
253 tangentAttrib
= glGetAttribLocation_func(program
, "Tangent");
254 printf("Tangent Attrib: %d\n", tangentAttrib
);
256 assert(tangentAttrib
>= 0);
258 CheckError(__LINE__
);
260 glClearColor(0.4f
, 0.4f
, 0.8f
, 0.0f
);
262 glEnable(GL_DEPTH_TEST
);
269 ParseOptions(int argc
, char *argv
[])
272 for (i
= 1; i
< argc
; i
++) {
273 if (strcmp(argv
[i
], "-fs") == 0) {
274 FragProgFile
= argv
[i
+1];
276 else if (strcmp(argv
[i
], "-vs") == 0) {
277 VertProgFile
= argv
[i
+1];
284 main(int argc
, char *argv
[])
286 glutInit(&argc
, argv
);
287 glutInitWindowPosition( 0, 0);
288 glutInitWindowSize(400, 400);
289 glutInitDisplayMode(GLUT_RGB
| GLUT_DOUBLE
| GLUT_DEPTH
);
290 win
= glutCreateWindow(argv
[0]);
291 glutReshapeFunc(Reshape
);
292 glutKeyboardFunc(Key
);
293 glutSpecialFunc(SpecialKey
);
294 glutDisplayFunc(Redisplay
);
295 ParseOptions(argc
, argv
);