1 /*
2 * Mesa 3-D graphics library
3 * Version: 7.0.3
4 *
5 * Copyright (C) 1999-2007 Brian Paul All Rights Reserved.
6 *
7 * Permission is hereby granted, free of charge, to any person obtaining a
8 * copy of this software and associated documentation files (the "Software"),
9 * to deal in the Software without restriction, including without limitation
10 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
11 * and/or sell copies of the Software, and to permit persons to whom the
12 * Software is furnished to do so, subject to the following conditions:
13 *
14 * The above copyright notice and this permission notice shall be included
15 * in all copies or substantial portions of the Software.
16 *
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
18 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
20 * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
21 * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
22 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
23 */
24
25 #include "main/glheader.h"
26 #include "main/colormac.h"
27 #include "main/samplerobj.h"
28 #include "program/prog_instruction.h"
29
30 #include "s_context.h"
31 #include "s_fragprog.h"
32 #include "s_span.h"
33
34 /**
35 * \brief Should swrast use a fragment program?
36 *
37 * \return true if the current fragment program exists and is not the fixed
38 * function fragment program
39 */
40 GLboolean
_swrast_use_fragment_program(struct gl_context * ctx)41 _swrast_use_fragment_program(struct gl_context *ctx)
42 {
43 struct gl_fragment_program *fp = ctx->FragmentProgram._Current;
44 return fp && !(fp == ctx->FragmentProgram._TexEnvProgram
45 && fp->Base.NumInstructions == 0);
46 }
47
48 /**
49 * Apply texture object's swizzle (X/Y/Z/W/0/1) to incoming 'texel'
50 * and return results in 'colorOut'.
51 */
52 static inline void
swizzle_texel(const GLfloat texel[4],GLfloat colorOut[4],GLuint swizzle)53 swizzle_texel(const GLfloat texel[4], GLfloat colorOut[4], GLuint swizzle)
54 {
55 if (swizzle == SWIZZLE_NOOP) {
56 COPY_4V(colorOut, texel);
57 }
58 else {
59 GLfloat vector[6];
60 vector[SWIZZLE_X] = texel[0];
61 vector[SWIZZLE_Y] = texel[1];
62 vector[SWIZZLE_Z] = texel[2];
63 vector[SWIZZLE_W] = texel[3];
64 vector[SWIZZLE_ZERO] = 0.0F;
65 vector[SWIZZLE_ONE] = 1.0F;
66 colorOut[0] = vector[GET_SWZ(swizzle, 0)];
67 colorOut[1] = vector[GET_SWZ(swizzle, 1)];
68 colorOut[2] = vector[GET_SWZ(swizzle, 2)];
69 colorOut[3] = vector[GET_SWZ(swizzle, 3)];
70 }
71 }
72
73
74 /**
75 * Fetch a texel with given lod.
76 * Called via machine->FetchTexelLod()
77 */
78 static void
fetch_texel_lod(struct gl_context * ctx,const GLfloat texcoord[4],GLfloat lambda,GLuint unit,GLfloat color[4])79 fetch_texel_lod( struct gl_context *ctx, const GLfloat texcoord[4], GLfloat lambda,
80 GLuint unit, GLfloat color[4] )
81 {
82 const struct gl_texture_object *texObj = ctx->Texture.Unit[unit]._Current;
83
84 if (texObj) {
85 SWcontext *swrast = SWRAST_CONTEXT(ctx);
86 GLfloat rgba[4];
87 const struct gl_sampler_object *samp = _mesa_get_samplerobj(ctx, unit);
88
89 lambda = CLAMP(lambda, samp->MinLod, samp->MaxLod);
90
91 swrast->TextureSample[unit](ctx, samp, ctx->Texture.Unit[unit]._Current,
92 1, (const GLfloat (*)[4]) texcoord,
93 &lambda, &rgba);
94 swizzle_texel(rgba, color, texObj->_Swizzle);
95 }
96 else {
97 ASSIGN_4V(color, 0.0F, 0.0F, 0.0F, 1.0F);
98 }
99 }
100
101
102 /**
103 * Fetch a texel with the given partial derivatives to compute a level
104 * of detail in the mipmap.
105 * Called via machine->FetchTexelDeriv()
106 * \param lodBias the lod bias which may be specified by a TXB instruction,
107 * otherwise zero.
108 */
109 static void
fetch_texel_deriv(struct gl_context * ctx,const GLfloat texcoord[4],const GLfloat texdx[4],const GLfloat texdy[4],GLfloat lodBias,GLuint unit,GLfloat color[4])110 fetch_texel_deriv( struct gl_context *ctx, const GLfloat texcoord[4],
111 const GLfloat texdx[4], const GLfloat texdy[4],
112 GLfloat lodBias, GLuint unit, GLfloat color[4] )
113 {
114 SWcontext *swrast = SWRAST_CONTEXT(ctx);
115 const struct gl_texture_unit *texUnit = &ctx->Texture.Unit[unit];
116 const struct gl_texture_object *texObj = texUnit->_Current;
117
118 if (texObj) {
119 const struct gl_texture_image *texImg =
120 texObj->Image[0][texObj->BaseLevel];
121 const struct swrast_texture_image *swImg =
122 swrast_texture_image_const(texImg);
123 const struct gl_sampler_object *samp = _mesa_get_samplerobj(ctx, unit);
124 const GLfloat texW = (GLfloat) swImg->WidthScale;
125 const GLfloat texH = (GLfloat) swImg->HeightScale;
126 GLfloat lambda;
127 GLfloat rgba[4];
128
129 lambda = _swrast_compute_lambda(texdx[0], texdy[0], /* ds/dx, ds/dy */
130 texdx[1], texdy[1], /* dt/dx, dt/dy */
131 texdx[3], texdy[3], /* dq/dx, dq/dy */
132 texW, texH,
133 texcoord[0], texcoord[1], texcoord[3],
134 1.0F / texcoord[3]);
135
136 lambda += lodBias + texUnit->LodBias + samp->LodBias;
137
138 lambda = CLAMP(lambda, samp->MinLod, samp->MaxLod);
139
140 swrast->TextureSample[unit](ctx, samp, ctx->Texture.Unit[unit]._Current,
141 1, (const GLfloat (*)[4]) texcoord,
142 &lambda, &rgba);
143 swizzle_texel(rgba, color, texObj->_Swizzle);
144 }
145 else {
146 ASSIGN_4V(color, 0.0F, 0.0F, 0.0F, 1.0F);
147 }
148 }
149
150
151 /**
152 * Initialize the virtual fragment program machine state prior to running
153 * fragment program on a fragment. This involves initializing the input
154 * registers, condition codes, etc.
155 * \param machine the virtual machine state to init
156 * \param program the fragment program we're about to run
157 * \param span the span of pixels we'll operate on
158 * \param col which element (column) of the span we'll operate on
159 */
160 static void
init_machine(struct gl_context * ctx,struct gl_program_machine * machine,const struct gl_fragment_program * program,const SWspan * span,GLuint col)161 init_machine(struct gl_context *ctx, struct gl_program_machine *machine,
162 const struct gl_fragment_program *program,
163 const SWspan *span, GLuint col)
164 {
165 GLfloat *wpos = span->array->attribs[FRAG_ATTRIB_WPOS][col];
166
167 if (program->Base.Target == GL_FRAGMENT_PROGRAM_NV) {
168 /* Clear temporary registers (undefined for ARB_f_p) */
169 memset(machine->Temporaries, 0, MAX_PROGRAM_TEMPS * 4 * sizeof(GLfloat));
170 }
171
172 /* ARB_fragment_coord_conventions */
173 if (program->OriginUpperLeft)
174 wpos[1] = ctx->DrawBuffer->Height - 1 - wpos[1];
175 if (!program->PixelCenterInteger) {
176 wpos[0] += 0.5F;
177 wpos[1] += 0.5F;
178 }
179
180 /* Setup pointer to input attributes */
181 machine->Attribs = span->array->attribs;
182
183 machine->DerivX = (GLfloat (*)[4]) span->attrStepX;
184 machine->DerivY = (GLfloat (*)[4]) span->attrStepY;
185 machine->NumDeriv = FRAG_ATTRIB_MAX;
186
187 machine->Samplers = program->Base.SamplerUnits;
188
189 /* if running a GLSL program (not ARB_fragment_program) */
190 if (ctx->Shader.CurrentFragmentProgram) {
191 /* Store front/back facing value */
192 machine->Attribs[FRAG_ATTRIB_FACE][col][0] = 1.0F - span->facing;
193 }
194
195 machine->CurElement = col;
196
197 /* init condition codes */
198 machine->CondCodes[0] = COND_EQ;
199 machine->CondCodes[1] = COND_EQ;
200 machine->CondCodes[2] = COND_EQ;
201 machine->CondCodes[3] = COND_EQ;
202
203 /* init call stack */
204 machine->StackDepth = 0;
205
206 machine->FetchTexelLod = fetch_texel_lod;
207 machine->FetchTexelDeriv = fetch_texel_deriv;
208 }
209
210
211 /**
212 * Run fragment program on the pixels in span from 'start' to 'end' - 1.
213 */
214 static void
run_program(struct gl_context * ctx,SWspan * span,GLuint start,GLuint end)215 run_program(struct gl_context *ctx, SWspan *span, GLuint start, GLuint end)
216 {
217 SWcontext *swrast = SWRAST_CONTEXT(ctx);
218 const struct gl_fragment_program *program = ctx->FragmentProgram._Current;
219 const GLbitfield64 outputsWritten = program->Base.OutputsWritten;
220 struct gl_program_machine *machine = &swrast->FragProgMachine;
221 GLuint i;
222
223 for (i = start; i < end; i++) {
224 if (span->array->mask[i]) {
225 init_machine(ctx, machine, program, span, i);
226
227 if (_mesa_execute_program(ctx, &program->Base, machine)) {
228
229 /* Store result color */
230 if (outputsWritten & BITFIELD64_BIT(FRAG_RESULT_COLOR)) {
231 COPY_4V(span->array->attribs[FRAG_ATTRIB_COL0][i],
232 machine->Outputs[FRAG_RESULT_COLOR]);
233 }
234 else {
235 /* Multiple drawbuffers / render targets
236 * Note that colors beyond 0 and 1 will overwrite other
237 * attributes, such as FOGC, TEX0, TEX1, etc. That's OK.
238 */
239 GLuint buf;
240 for (buf = 0; buf < ctx->DrawBuffer->_NumColorDrawBuffers; buf++) {
241 if (outputsWritten & BITFIELD64_BIT(FRAG_RESULT_DATA0 + buf)) {
242 COPY_4V(span->array->attribs[FRAG_ATTRIB_COL0 + buf][i],
243 machine->Outputs[FRAG_RESULT_DATA0 + buf]);
244 }
245 }
246 }
247
248 /* Store result depth/z */
249 if (outputsWritten & BITFIELD64_BIT(FRAG_RESULT_DEPTH)) {
250 const GLfloat depth = machine->Outputs[FRAG_RESULT_DEPTH][2];
251 if (depth <= 0.0)
252 span->array->z[i] = 0;
253 else if (depth >= 1.0)
254 span->array->z[i] = ctx->DrawBuffer->_DepthMax;
255 else
256 span->array->z[i] =
257 (GLuint) (depth * ctx->DrawBuffer->_DepthMaxF + 0.5F);
258 }
259 }
260 else {
261 /* killed fragment */
262 span->array->mask[i] = GL_FALSE;
263 span->writeAll = GL_FALSE;
264 }
265 }
266 }
267 }
268
269
270 /**
271 * Execute the current fragment program for all the fragments
272 * in the given span.
273 */
274 void
_swrast_exec_fragment_program(struct gl_context * ctx,SWspan * span)275 _swrast_exec_fragment_program( struct gl_context *ctx, SWspan *span )
276 {
277 const struct gl_fragment_program *program = ctx->FragmentProgram._Current;
278
279 /* incoming colors should be floats */
280 if (program->Base.InputsRead & FRAG_BIT_COL0) {
281 ASSERT(span->array->ChanType == GL_FLOAT);
282 }
283
284 run_program(ctx, span, 0, span->end);
285
286 if (program->Base.OutputsWritten & BITFIELD64_BIT(FRAG_RESULT_COLOR)) {
287 span->interpMask &= ~SPAN_RGBA;
288 span->arrayMask |= SPAN_RGBA;
289 }
290
291 if (program->Base.OutputsWritten & BITFIELD64_BIT(FRAG_RESULT_DEPTH)) {
292 span->interpMask &= ~SPAN_Z;
293 span->arrayMask |= SPAN_Z;
294 }
295 }
296
297