2 * Mesa 3-D graphics library
4 * Copyright (C) 1999-2007 Brian Paul All Rights Reserved.
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the "Software"),
8 * to deal in the Software without restriction, including without limitation
9 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
10 * and/or sell copies of the Software, and to permit persons to whom the
11 * Software is furnished to do so, subject to the following conditions:
13 * The above copyright notice and this permission notice shall be included
14 * in all copies or substantial portions of the Software.
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
17 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
20 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
21 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
22 * OTHER DEALINGS IN THE SOFTWARE.
27 #include "main/glheader.h"
28 #include "main/colormac.h"
29 #include "main/feedback.h"
30 #include "main/light.h"
31 #include "main/macros.h"
32 #include "util/simple_list.h"
33 #include "main/mtypes.h"
35 #include "math/m_matrix.h"
41 * Clip a point against the view volume.
43 * \param v vertex vector describing the point to clip.
45 * \return zero if outside view volume, or one if inside.
48 viewclip_point_xy( const GLfloat v
[] )
50 if ( v
[0] > v
[3] || v
[0] < -v
[3]
51 || v
[1] > v
[3] || v
[1] < -v
[3] ) {
61 * Clip a point against the far/near Z clipping planes.
63 * \param v vertex vector describing the point to clip.
65 * \return zero if outside view volume, or one if inside.
68 viewclip_point_z( const GLfloat v
[] )
70 if (v
[2] > v
[3] || v
[2] < -v
[3] ) {
80 * Clip a point against the user clipping planes.
82 * \param ctx GL context.
83 * \param v vertex vector describing the point to clip.
85 * \return zero if the point was clipped, or one otherwise.
88 userclip_point( struct gl_context
*ctx
, const GLfloat v
[] )
92 for (p
= 0; p
< ctx
->Const
.MaxClipPlanes
; p
++) {
93 if (ctx
->Transform
.ClipPlanesEnabled
& (1 << p
)) {
94 GLfloat dot
= v
[0] * ctx
->Transform
._ClipUserPlane
[p
][0]
95 + v
[1] * ctx
->Transform
._ClipUserPlane
[p
][1]
96 + v
[2] * ctx
->Transform
._ClipUserPlane
[p
][2]
97 + v
[3] * ctx
->Transform
._ClipUserPlane
[p
][3];
109 * Compute lighting for the raster position. RGB modes computed.
110 * \param ctx the context
111 * \param vertex vertex location
112 * \param normal normal vector
113 * \param Rcolor returned color
114 * \param Rspec returned specular color (if separate specular enabled)
117 shade_rastpos(struct gl_context
*ctx
,
118 const GLfloat vertex
[4],
119 const GLfloat normal
[3],
123 /*const*/ GLfloat (*base
)[3] = ctx
->Light
._BaseColor
;
124 const struct gl_light
*light
;
125 GLfloat diffuseColor
[4], specularColor
[4]; /* for RGB mode only */
127 COPY_3V(diffuseColor
, base
[0]);
128 diffuseColor
[3] = CLAMP(
129 ctx
->Light
.Material
.Attrib
[MAT_ATTRIB_FRONT_DIFFUSE
][3], 0.0F
, 1.0F
);
130 ASSIGN_4V(specularColor
, 0.0, 0.0, 0.0, 1.0);
132 foreach (light
, &ctx
->Light
.EnabledList
) {
133 GLfloat attenuation
= 1.0;
134 GLfloat VP
[3]; /* vector from vertex to light pos */
136 GLfloat diffuseContrib
[3], specularContrib
[3];
138 if (!(light
->_Flags
& LIGHT_POSITIONAL
)) {
139 /* light at infinity */
140 COPY_3V(VP
, light
->_VP_inf_norm
);
141 attenuation
= light
->_VP_inf_spot_attenuation
;
144 /* local/positional light */
147 /* VP = vector from vertex pos to light[i].pos */
148 SUB_3V(VP
, light
->_Position
, vertex
);
150 d
= (GLfloat
) LEN_3FV( VP
);
153 GLfloat invd
= 1.0F
/ d
;
154 SELF_SCALE_SCALAR_3V(VP
, invd
);
158 attenuation
= 1.0F
/ (light
->ConstantAttenuation
+ d
*
159 (light
->LinearAttenuation
+ d
*
160 light
->QuadraticAttenuation
));
162 if (light
->_Flags
& LIGHT_SPOT
) {
163 GLfloat PV_dot_dir
= - DOT3(VP
, light
->_NormSpotDirection
);
165 if (PV_dot_dir
<light
->_CosCutoff
) {
169 GLfloat spot
= powf(PV_dot_dir
, light
->SpotExponent
);
175 if (attenuation
< 1e-3)
178 n_dot_VP
= DOT3( normal
, VP
);
180 if (n_dot_VP
< 0.0F
) {
181 ACC_SCALE_SCALAR_3V(diffuseColor
, attenuation
, light
->_MatAmbient
[0]);
185 /* Ambient + diffuse */
186 COPY_3V(diffuseContrib
, light
->_MatAmbient
[0]);
187 ACC_SCALE_SCALAR_3V(diffuseContrib
, n_dot_VP
, light
->_MatDiffuse
[0]);
194 ASSIGN_3V(specularContrib
, 0.0, 0.0, 0.0);
196 if (ctx
->Light
.Model
.LocalViewer
) {
204 else if (light
->_Flags
& LIGHT_POSITIONAL
) {
205 ACC_3V(VP
, ctx
->_EyeZDir
);
210 h
= light
->_h_inf_norm
;
213 n_dot_h
= DOT3(normal
, h
);
215 if (n_dot_h
> 0.0F
) {
219 shine
= ctx
->Light
.Material
.Attrib
[MAT_ATTRIB_FRONT_SHININESS
][0];
220 spec_coef
= powf(n_dot_h
, shine
);
222 if (spec_coef
> 1.0e-10) {
223 if (ctx
->Light
.Model
.ColorControl
==GL_SEPARATE_SPECULAR_COLOR
) {
224 ACC_SCALE_SCALAR_3V( specularContrib
, spec_coef
,
225 light
->_MatSpecular
[0]);
228 ACC_SCALE_SCALAR_3V( diffuseContrib
, spec_coef
,
229 light
->_MatSpecular
[0]);
235 ACC_SCALE_SCALAR_3V( diffuseColor
, attenuation
, diffuseContrib
);
236 ACC_SCALE_SCALAR_3V( specularColor
, attenuation
, specularContrib
);
239 Rcolor
[0] = CLAMP(diffuseColor
[0], 0.0F
, 1.0F
);
240 Rcolor
[1] = CLAMP(diffuseColor
[1], 0.0F
, 1.0F
);
241 Rcolor
[2] = CLAMP(diffuseColor
[2], 0.0F
, 1.0F
);
242 Rcolor
[3] = CLAMP(diffuseColor
[3], 0.0F
, 1.0F
);
243 Rspec
[0] = CLAMP(specularColor
[0], 0.0F
, 1.0F
);
244 Rspec
[1] = CLAMP(specularColor
[1], 0.0F
, 1.0F
);
245 Rspec
[2] = CLAMP(specularColor
[2], 0.0F
, 1.0F
);
246 Rspec
[3] = CLAMP(specularColor
[3], 0.0F
, 1.0F
);
251 * Do texgen needed for glRasterPos.
252 * \param ctx rendering context
253 * \param vObj object-space vertex coordinate
254 * \param vEye eye-space vertex coordinate
255 * \param normal vertex normal
256 * \param unit texture unit number
257 * \param texcoord incoming texcoord and resulting texcoord
260 compute_texgen(struct gl_context
*ctx
, const GLfloat vObj
[4], const GLfloat vEye
[4],
261 const GLfloat normal
[3], GLuint unit
, GLfloat texcoord
[4])
263 const struct gl_texture_unit
*texUnit
= &ctx
->Texture
.Unit
[unit
];
265 /* always compute sphere map terms, just in case */
266 GLfloat u
[3], two_nu
, rx
, ry
, rz
, m
, mInv
;
269 two_nu
= 2.0F
* DOT3(normal
, u
);
270 rx
= u
[0] - normal
[0] * two_nu
;
271 ry
= u
[1] - normal
[1] * two_nu
;
272 rz
= u
[2] - normal
[2] * two_nu
;
273 m
= rx
* rx
+ ry
* ry
+ (rz
+ 1.0F
) * (rz
+ 1.0F
);
275 mInv
= 0.5F
* INV_SQRTF(m
);
279 if (texUnit
->TexGenEnabled
& S_BIT
) {
280 switch (texUnit
->GenS
.Mode
) {
281 case GL_OBJECT_LINEAR
:
282 texcoord
[0] = DOT4(vObj
, texUnit
->GenS
.ObjectPlane
);
285 texcoord
[0] = DOT4(vEye
, texUnit
->GenS
.EyePlane
);
288 texcoord
[0] = rx
* mInv
+ 0.5F
;
290 case GL_REFLECTION_MAP
:
294 texcoord
[0] = normal
[0];
297 _mesa_problem(ctx
, "Bad S texgen in compute_texgen()");
302 if (texUnit
->TexGenEnabled
& T_BIT
) {
303 switch (texUnit
->GenT
.Mode
) {
304 case GL_OBJECT_LINEAR
:
305 texcoord
[1] = DOT4(vObj
, texUnit
->GenT
.ObjectPlane
);
308 texcoord
[1] = DOT4(vEye
, texUnit
->GenT
.EyePlane
);
311 texcoord
[1] = ry
* mInv
+ 0.5F
;
313 case GL_REFLECTION_MAP
:
317 texcoord
[1] = normal
[1];
320 _mesa_problem(ctx
, "Bad T texgen in compute_texgen()");
325 if (texUnit
->TexGenEnabled
& R_BIT
) {
326 switch (texUnit
->GenR
.Mode
) {
327 case GL_OBJECT_LINEAR
:
328 texcoord
[2] = DOT4(vObj
, texUnit
->GenR
.ObjectPlane
);
331 texcoord
[2] = DOT4(vEye
, texUnit
->GenR
.EyePlane
);
333 case GL_REFLECTION_MAP
:
337 texcoord
[2] = normal
[2];
340 _mesa_problem(ctx
, "Bad R texgen in compute_texgen()");
345 if (texUnit
->TexGenEnabled
& Q_BIT
) {
346 switch (texUnit
->GenQ
.Mode
) {
347 case GL_OBJECT_LINEAR
:
348 texcoord
[3] = DOT4(vObj
, texUnit
->GenQ
.ObjectPlane
);
351 texcoord
[3] = DOT4(vEye
, texUnit
->GenQ
.EyePlane
);
354 _mesa_problem(ctx
, "Bad Q texgen in compute_texgen()");
362 * glRasterPos transformation. Typically called via ctx->Driver.RasterPos().
363 * XXX some of this code (such as viewport xform, clip testing and setting
364 * of ctx->Current.Raster* fields) could get lifted up into the
365 * main/rasterpos.c code.
367 * \param vObj vertex position in object space
370 _tnl_RasterPos(struct gl_context
*ctx
, const GLfloat vObj
[4])
372 if (ctx
->VertexProgram
._Enabled
) {
373 /* XXX implement this */
374 _mesa_problem(ctx
, "Vertex programs not implemented for glRasterPos");
378 GLfloat eye
[4], clip
[4], ndc
[3], d
;
379 GLfloat
*norm
, eyenorm
[3];
380 GLfloat
*objnorm
= ctx
->Current
.Attrib
[VERT_ATTRIB_NORMAL
];
382 /* apply modelview matrix: eye = MV * obj */
383 TRANSFORM_POINT( eye
, ctx
->ModelviewMatrixStack
.Top
->m
, vObj
);
384 /* apply projection matrix: clip = Proj * eye */
385 TRANSFORM_POINT( clip
, ctx
->ProjectionMatrixStack
.Top
->m
, eye
);
387 /* clip to view volume. */
388 if (!ctx
->Transform
.DepthClamp
) {
389 if (viewclip_point_z(clip
) == 0) {
390 ctx
->Current
.RasterPosValid
= GL_FALSE
;
394 if (!ctx
->Transform
.RasterPositionUnclipped
) {
395 if (viewclip_point_xy(clip
) == 0) {
396 ctx
->Current
.RasterPosValid
= GL_FALSE
;
401 /* clip to user clipping planes */
402 if (ctx
->Transform
.ClipPlanesEnabled
&& !userclip_point(ctx
, clip
)) {
403 ctx
->Current
.RasterPosValid
= GL_FALSE
;
408 d
= (clip
[3] == 0.0F
) ? 1.0F
: 1.0F
/ clip
[3];
409 ndc
[0] = clip
[0] * d
;
410 ndc
[1] = clip
[1] * d
;
411 ndc
[2] = clip
[2] * d
;
412 /* wincoord = viewport_mapping(ndc) */
413 ctx
->Current
.RasterPos
[0] = (ndc
[0] * ctx
->ViewportArray
[0]._WindowMap
.m
[MAT_SX
]
414 + ctx
->ViewportArray
[0]._WindowMap
.m
[MAT_TX
]);
415 ctx
->Current
.RasterPos
[1] = (ndc
[1] * ctx
->ViewportArray
[0]._WindowMap
.m
[MAT_SY
]
416 + ctx
->ViewportArray
[0]._WindowMap
.m
[MAT_TY
]);
417 ctx
->Current
.RasterPos
[2] = (ndc
[2] * ctx
->ViewportArray
[0]._WindowMap
.m
[MAT_SZ
]
418 + ctx
->ViewportArray
[0]._WindowMap
.m
[MAT_TZ
])
419 / ctx
->DrawBuffer
->_DepthMaxF
;
420 ctx
->Current
.RasterPos
[3] = clip
[3];
422 if (ctx
->Transform
.DepthClamp
) {
423 ctx
->Current
.RasterPos
[3] = CLAMP(ctx
->Current
.RasterPos
[3],
424 ctx
->ViewportArray
[0].Near
,
425 ctx
->ViewportArray
[0].Far
);
428 /* compute raster distance */
429 if (ctx
->Fog
.FogCoordinateSource
== GL_FOG_COORDINATE_EXT
)
430 ctx
->Current
.RasterDistance
= ctx
->Current
.Attrib
[VERT_ATTRIB_FOG
][0];
432 ctx
->Current
.RasterDistance
=
433 sqrtf( eye
[0]*eye
[0] + eye
[1]*eye
[1] + eye
[2]*eye
[2] );
435 /* compute transformed normal vector (for lighting or texgen) */
436 if (ctx
->_NeedEyeCoords
) {
437 const GLfloat
*inv
= ctx
->ModelviewMatrixStack
.Top
->inv
;
438 TRANSFORM_NORMAL( eyenorm
, objnorm
, inv
);
445 /* update raster color */
446 if (ctx
->Light
.Enabled
) {
448 shade_rastpos( ctx
, vObj
, norm
,
449 ctx
->Current
.RasterColor
,
450 ctx
->Current
.RasterSecondaryColor
);
453 /* use current color */
454 COPY_4FV(ctx
->Current
.RasterColor
,
455 ctx
->Current
.Attrib
[VERT_ATTRIB_COLOR0
]);
456 COPY_4FV(ctx
->Current
.RasterSecondaryColor
,
457 ctx
->Current
.Attrib
[VERT_ATTRIB_COLOR1
]);
463 for (u
= 0; u
< ctx
->Const
.MaxTextureCoordUnits
; u
++) {
465 COPY_4V(tc
, ctx
->Current
.Attrib
[VERT_ATTRIB_TEX0
+ u
]);
466 if (ctx
->Texture
.Unit
[u
].TexGenEnabled
) {
467 compute_texgen(ctx
, vObj
, eye
, norm
, u
, tc
);
469 TRANSFORM_POINT(ctx
->Current
.RasterTexCoords
[u
],
470 ctx
->TextureMatrixStack
[u
].Top
->m
, tc
);
474 ctx
->Current
.RasterPosValid
= GL_TRUE
;
477 if (ctx
->RenderMode
== GL_SELECT
) {
478 _mesa_update_hitflag( ctx
, ctx
->Current
.RasterPos
[2] );