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.
26 #include "main/glheader.h"
27 #include "main/colormac.h"
28 #include "main/feedback.h"
29 #include "main/light.h"
30 #include "main/macros.h"
31 #include "main/simple_list.h"
32 #include "main/mtypes.h"
34 #include "math/m_matrix.h"
40 * Clip a point against the view volume.
42 * \param v vertex vector describing the point to clip.
44 * \return zero if outside view volume, or one if inside.
47 viewclip_point_xy( const GLfloat v
[] )
49 if ( v
[0] > v
[3] || v
[0] < -v
[3]
50 || v
[1] > v
[3] || v
[1] < -v
[3] ) {
60 * Clip a point against the far/near Z clipping planes.
62 * \param v vertex vector describing the point to clip.
64 * \return zero if outside view volume, or one if inside.
67 viewclip_point_z( const GLfloat v
[] )
69 if (v
[2] > v
[3] || v
[2] < -v
[3] ) {
79 * Clip a point against the user clipping planes.
81 * \param ctx GL context.
82 * \param v vertex vector describing the point to clip.
84 * \return zero if the point was clipped, or one otherwise.
87 userclip_point( struct gl_context
*ctx
, const GLfloat v
[] )
91 for (p
= 0; p
< ctx
->Const
.MaxClipPlanes
; p
++) {
92 if (ctx
->Transform
.ClipPlanesEnabled
& (1 << p
)) {
93 GLfloat dot
= v
[0] * ctx
->Transform
._ClipUserPlane
[p
][0]
94 + v
[1] * ctx
->Transform
._ClipUserPlane
[p
][1]
95 + v
[2] * ctx
->Transform
._ClipUserPlane
[p
][2]
96 + v
[3] * ctx
->Transform
._ClipUserPlane
[p
][3];
108 * Compute lighting for the raster position. RGB modes computed.
109 * \param ctx the context
110 * \param vertex vertex location
111 * \param normal normal vector
112 * \param Rcolor returned color
113 * \param Rspec returned specular color (if separate specular enabled)
116 shade_rastpos(struct gl_context
*ctx
,
117 const GLfloat vertex
[4],
118 const GLfloat normal
[3],
122 /*const*/ GLfloat (*base
)[3] = ctx
->Light
._BaseColor
;
123 const struct gl_light
*light
;
124 GLfloat diffuseColor
[4], specularColor
[4]; /* for RGB mode only */
126 COPY_3V(diffuseColor
, base
[0]);
127 diffuseColor
[3] = CLAMP(
128 ctx
->Light
.Material
.Attrib
[MAT_ATTRIB_FRONT_DIFFUSE
][3], 0.0F
, 1.0F
);
129 ASSIGN_4V(specularColor
, 0.0, 0.0, 0.0, 1.0);
131 foreach (light
, &ctx
->Light
.EnabledList
) {
132 GLfloat attenuation
= 1.0;
133 GLfloat VP
[3]; /* vector from vertex to light pos */
135 GLfloat diffuseContrib
[3], specularContrib
[3];
137 if (!(light
->_Flags
& LIGHT_POSITIONAL
)) {
138 /* light at infinity */
139 COPY_3V(VP
, light
->_VP_inf_norm
);
140 attenuation
= light
->_VP_inf_spot_attenuation
;
143 /* local/positional light */
146 /* VP = vector from vertex pos to light[i].pos */
147 SUB_3V(VP
, light
->_Position
, vertex
);
149 d
= (GLfloat
) LEN_3FV( VP
);
152 GLfloat invd
= 1.0F
/ d
;
153 SELF_SCALE_SCALAR_3V(VP
, invd
);
157 attenuation
= 1.0F
/ (light
->ConstantAttenuation
+ d
*
158 (light
->LinearAttenuation
+ d
*
159 light
->QuadraticAttenuation
));
161 if (light
->_Flags
& LIGHT_SPOT
) {
162 GLfloat PV_dot_dir
= - DOT3(VP
, light
->_NormSpotDirection
);
164 if (PV_dot_dir
<light
->_CosCutoff
) {
168 GLfloat spot
= powf(PV_dot_dir
, light
->SpotExponent
);
174 if (attenuation
< 1e-3)
177 n_dot_VP
= DOT3( normal
, VP
);
179 if (n_dot_VP
< 0.0F
) {
180 ACC_SCALE_SCALAR_3V(diffuseColor
, attenuation
, light
->_MatAmbient
[0]);
184 /* Ambient + diffuse */
185 COPY_3V(diffuseContrib
, light
->_MatAmbient
[0]);
186 ACC_SCALE_SCALAR_3V(diffuseContrib
, n_dot_VP
, light
->_MatDiffuse
[0]);
193 ASSIGN_3V(specularContrib
, 0.0, 0.0, 0.0);
195 if (ctx
->Light
.Model
.LocalViewer
) {
203 else if (light
->_Flags
& LIGHT_POSITIONAL
) {
204 ACC_3V(VP
, ctx
->_EyeZDir
);
209 h
= light
->_h_inf_norm
;
212 n_dot_h
= DOT3(normal
, h
);
214 if (n_dot_h
> 0.0F
) {
218 shine
= ctx
->Light
.Material
.Attrib
[MAT_ATTRIB_FRONT_SHININESS
][0];
219 spec_coef
= powf(n_dot_h
, shine
);
221 if (spec_coef
> 1.0e-10) {
222 if (ctx
->Light
.Model
.ColorControl
==GL_SEPARATE_SPECULAR_COLOR
) {
223 ACC_SCALE_SCALAR_3V( specularContrib
, spec_coef
,
224 light
->_MatSpecular
[0]);
227 ACC_SCALE_SCALAR_3V( diffuseContrib
, spec_coef
,
228 light
->_MatSpecular
[0]);
234 ACC_SCALE_SCALAR_3V( diffuseColor
, attenuation
, diffuseContrib
);
235 ACC_SCALE_SCALAR_3V( specularColor
, attenuation
, specularContrib
);
238 Rcolor
[0] = CLAMP(diffuseColor
[0], 0.0F
, 1.0F
);
239 Rcolor
[1] = CLAMP(diffuseColor
[1], 0.0F
, 1.0F
);
240 Rcolor
[2] = CLAMP(diffuseColor
[2], 0.0F
, 1.0F
);
241 Rcolor
[3] = CLAMP(diffuseColor
[3], 0.0F
, 1.0F
);
242 Rspec
[0] = CLAMP(specularColor
[0], 0.0F
, 1.0F
);
243 Rspec
[1] = CLAMP(specularColor
[1], 0.0F
, 1.0F
);
244 Rspec
[2] = CLAMP(specularColor
[2], 0.0F
, 1.0F
);
245 Rspec
[3] = CLAMP(specularColor
[3], 0.0F
, 1.0F
);
250 * Do texgen needed for glRasterPos.
251 * \param ctx rendering context
252 * \param vObj object-space vertex coordinate
253 * \param vEye eye-space vertex coordinate
254 * \param normal vertex normal
255 * \param unit texture unit number
256 * \param texcoord incoming texcoord and resulting texcoord
259 compute_texgen(struct gl_context
*ctx
, const GLfloat vObj
[4], const GLfloat vEye
[4],
260 const GLfloat normal
[3], GLuint unit
, GLfloat texcoord
[4])
262 const struct gl_texture_unit
*texUnit
= &ctx
->Texture
.Unit
[unit
];
264 /* always compute sphere map terms, just in case */
265 GLfloat u
[3], two_nu
, rx
, ry
, rz
, m
, mInv
;
268 two_nu
= 2.0F
* DOT3(normal
, u
);
269 rx
= u
[0] - normal
[0] * two_nu
;
270 ry
= u
[1] - normal
[1] * two_nu
;
271 rz
= u
[2] - normal
[2] * two_nu
;
272 m
= rx
* rx
+ ry
* ry
+ (rz
+ 1.0F
) * (rz
+ 1.0F
);
274 mInv
= 0.5F
* INV_SQRTF(m
);
278 if (texUnit
->TexGenEnabled
& S_BIT
) {
279 switch (texUnit
->GenS
.Mode
) {
280 case GL_OBJECT_LINEAR
:
281 texcoord
[0] = DOT4(vObj
, texUnit
->GenS
.ObjectPlane
);
284 texcoord
[0] = DOT4(vEye
, texUnit
->GenS
.EyePlane
);
287 texcoord
[0] = rx
* mInv
+ 0.5F
;
289 case GL_REFLECTION_MAP
:
293 texcoord
[0] = normal
[0];
296 _mesa_problem(ctx
, "Bad S texgen in compute_texgen()");
301 if (texUnit
->TexGenEnabled
& T_BIT
) {
302 switch (texUnit
->GenT
.Mode
) {
303 case GL_OBJECT_LINEAR
:
304 texcoord
[1] = DOT4(vObj
, texUnit
->GenT
.ObjectPlane
);
307 texcoord
[1] = DOT4(vEye
, texUnit
->GenT
.EyePlane
);
310 texcoord
[1] = ry
* mInv
+ 0.5F
;
312 case GL_REFLECTION_MAP
:
316 texcoord
[1] = normal
[1];
319 _mesa_problem(ctx
, "Bad T texgen in compute_texgen()");
324 if (texUnit
->TexGenEnabled
& R_BIT
) {
325 switch (texUnit
->GenR
.Mode
) {
326 case GL_OBJECT_LINEAR
:
327 texcoord
[2] = DOT4(vObj
, texUnit
->GenR
.ObjectPlane
);
330 texcoord
[2] = DOT4(vEye
, texUnit
->GenR
.EyePlane
);
332 case GL_REFLECTION_MAP
:
336 texcoord
[2] = normal
[2];
339 _mesa_problem(ctx
, "Bad R texgen in compute_texgen()");
344 if (texUnit
->TexGenEnabled
& Q_BIT
) {
345 switch (texUnit
->GenQ
.Mode
) {
346 case GL_OBJECT_LINEAR
:
347 texcoord
[3] = DOT4(vObj
, texUnit
->GenQ
.ObjectPlane
);
350 texcoord
[3] = DOT4(vEye
, texUnit
->GenQ
.EyePlane
);
353 _mesa_problem(ctx
, "Bad Q texgen in compute_texgen()");
361 * glRasterPos transformation. Typically called via ctx->Driver.RasterPos().
362 * XXX some of this code (such as viewport xform, clip testing and setting
363 * of ctx->Current.Raster* fields) could get lifted up into the
364 * main/rasterpos.c code.
366 * \param vObj vertex position in object space
369 _tnl_RasterPos(struct gl_context
*ctx
, const GLfloat vObj
[4])
371 if (ctx
->VertexProgram
._Enabled
) {
372 /* XXX implement this */
373 _mesa_problem(ctx
, "Vertex programs not implemented for glRasterPos");
377 GLfloat eye
[4], clip
[4], ndc
[3], d
;
378 GLfloat
*norm
, eyenorm
[3];
379 GLfloat
*objnorm
= ctx
->Current
.Attrib
[VERT_ATTRIB_NORMAL
];
381 /* apply modelview matrix: eye = MV * obj */
382 TRANSFORM_POINT( eye
, ctx
->ModelviewMatrixStack
.Top
->m
, vObj
);
383 /* apply projection matrix: clip = Proj * eye */
384 TRANSFORM_POINT( clip
, ctx
->ProjectionMatrixStack
.Top
->m
, eye
);
386 /* clip to view volume. */
387 if (!ctx
->Transform
.DepthClamp
) {
388 if (viewclip_point_z(clip
) == 0) {
389 ctx
->Current
.RasterPosValid
= GL_FALSE
;
393 if (!ctx
->Transform
.RasterPositionUnclipped
) {
394 if (viewclip_point_xy(clip
) == 0) {
395 ctx
->Current
.RasterPosValid
= GL_FALSE
;
400 /* clip to user clipping planes */
401 if (ctx
->Transform
.ClipPlanesEnabled
&& !userclip_point(ctx
, clip
)) {
402 ctx
->Current
.RasterPosValid
= GL_FALSE
;
407 d
= (clip
[3] == 0.0F
) ? 1.0F
: 1.0F
/ clip
[3];
408 ndc
[0] = clip
[0] * d
;
409 ndc
[1] = clip
[1] * d
;
410 ndc
[2] = clip
[2] * d
;
411 /* wincoord = viewport_mapping(ndc) */
412 ctx
->Current
.RasterPos
[0] = (ndc
[0] * ctx
->ViewportArray
[0]._WindowMap
.m
[MAT_SX
]
413 + ctx
->ViewportArray
[0]._WindowMap
.m
[MAT_TX
]);
414 ctx
->Current
.RasterPos
[1] = (ndc
[1] * ctx
->ViewportArray
[0]._WindowMap
.m
[MAT_SY
]
415 + ctx
->ViewportArray
[0]._WindowMap
.m
[MAT_TY
]);
416 ctx
->Current
.RasterPos
[2] = (ndc
[2] * ctx
->ViewportArray
[0]._WindowMap
.m
[MAT_SZ
]
417 + ctx
->ViewportArray
[0]._WindowMap
.m
[MAT_TZ
])
418 / ctx
->DrawBuffer
->_DepthMaxF
;
419 ctx
->Current
.RasterPos
[3] = clip
[3];
421 if (ctx
->Transform
.DepthClamp
) {
422 ctx
->Current
.RasterPos
[3] = CLAMP(ctx
->Current
.RasterPos
[3],
423 ctx
->ViewportArray
[0].Near
,
424 ctx
->ViewportArray
[0].Far
);
427 /* compute raster distance */
428 if (ctx
->Fog
.FogCoordinateSource
== GL_FOG_COORDINATE_EXT
)
429 ctx
->Current
.RasterDistance
= ctx
->Current
.Attrib
[VERT_ATTRIB_FOG
][0];
431 ctx
->Current
.RasterDistance
=
432 sqrtf( eye
[0]*eye
[0] + eye
[1]*eye
[1] + eye
[2]*eye
[2] );
434 /* compute transformed normal vector (for lighting or texgen) */
435 if (ctx
->_NeedEyeCoords
) {
436 const GLfloat
*inv
= ctx
->ModelviewMatrixStack
.Top
->inv
;
437 TRANSFORM_NORMAL( eyenorm
, objnorm
, inv
);
444 /* update raster color */
445 if (ctx
->Light
.Enabled
) {
447 shade_rastpos( ctx
, vObj
, norm
,
448 ctx
->Current
.RasterColor
,
449 ctx
->Current
.RasterSecondaryColor
);
452 /* use current color */
453 COPY_4FV(ctx
->Current
.RasterColor
,
454 ctx
->Current
.Attrib
[VERT_ATTRIB_COLOR0
]);
455 COPY_4FV(ctx
->Current
.RasterSecondaryColor
,
456 ctx
->Current
.Attrib
[VERT_ATTRIB_COLOR1
]);
462 for (u
= 0; u
< ctx
->Const
.MaxTextureCoordUnits
; u
++) {
464 COPY_4V(tc
, ctx
->Current
.Attrib
[VERT_ATTRIB_TEX0
+ u
]);
465 if (ctx
->Texture
.Unit
[u
].TexGenEnabled
) {
466 compute_texgen(ctx
, vObj
, eye
, norm
, u
, tc
);
468 TRANSFORM_POINT(ctx
->Current
.RasterTexCoords
[u
],
469 ctx
->TextureMatrixStack
[u
].Top
->m
, tc
);
473 ctx
->Current
.RasterPosValid
= GL_TRUE
;
476 if (ctx
->RenderMode
== GL_SELECT
) {
477 _mesa_update_hitflag( ctx
, ctx
->Current
.RasterPos
[2] );