1 /* 2 * Mesa 3-D graphics library 3 * 4 * Copyright (C) 1999-2007 Brian Paul All Rights Reserved. 5 * 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: 12 * 13 * The above copyright notice and this permission notice shall be included 14 * in all copies or substantial portions of the Software. 15 * 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. 23 */ 24 25 #include "main/glheader.h" 26 #include "main/macros.h" 27 #include "main/samplerobj.h" 28 #include "main/teximage.h" 29 #include "program/prog_instruction.h" 30 31 #include "s_context.h" 32 #include "s_fragprog.h" 33 #include "s_span.h" 34 35 /** 36 * \brief Should swrast use a fragment program? 37 * 38 * \return true if the current fragment program exists and is not the fixed 39 * function fragment program 40 */ 41 GLboolean 42 _swrast_use_fragment_program(struct gl_context *ctx) 43 { 44 struct gl_program *fp = ctx->FragmentProgram._Current; 45 return fp && !(fp == ctx->FragmentProgram._TexEnvProgram 46 && fp->arb.NumInstructions == 0); 47 } 48 49 /** 50 * Apply texture object's swizzle (X/Y/Z/W/0/1) to incoming 'texel' 51 * and return results in 'colorOut'. 52 */ 53 static inline void 54 swizzle_texel(const GLfloat texel[4], GLfloat colorOut[4], GLuint swizzle) 55 { 56 if (swizzle == SWIZZLE_NOOP) { 57 COPY_4V(colorOut, texel); 58 } 59 else { 60 GLfloat vector[6]; 61 vector[SWIZZLE_X] = texel[0]; 62 vector[SWIZZLE_Y] = texel[1]; 63 vector[SWIZZLE_Z] = texel[2]; 64 vector[SWIZZLE_W] = texel[3]; 65 vector[SWIZZLE_ZERO] = 0.0F; 66 vector[SWIZZLE_ONE] = 1.0F; 67 colorOut[0] = vector[GET_SWZ(swizzle, 0)]; 68 colorOut[1] = vector[GET_SWZ(swizzle, 1)]; 69 colorOut[2] = vector[GET_SWZ(swizzle, 2)]; 70 colorOut[3] = vector[GET_SWZ(swizzle, 3)]; 71 } 72 } 73 74 75 /** 76 * Fetch a texel with given lod. 77 * Called via machine->FetchTexelLod() 78 */ 79 static void 80 fetch_texel_lod( struct gl_context *ctx, const GLfloat texcoord[4], GLfloat lambda, 81 GLuint unit, GLfloat color[4] ) 82 { 83 const struct gl_texture_object *texObj = ctx->Texture.Unit[unit]._Current; 84 85 if (texObj) { 86 SWcontext *swrast = SWRAST_CONTEXT(ctx); 87 GLfloat rgba[4]; 88 const struct gl_sampler_object *samp = _mesa_get_samplerobj(ctx, unit); 89 90 lambda = CLAMP(lambda, samp->MinLod, samp->MaxLod); 91 92 swrast->TextureSample[unit](ctx, samp, ctx->Texture.Unit[unit]._Current, 93 1, (const GLfloat (*)[4]) texcoord, 94 &lambda, &rgba); 95 swizzle_texel(rgba, color, texObj->_Swizzle); 96 } 97 else { 98 ASSIGN_4V(color, 0.0F, 0.0F, 0.0F, 1.0F); 99 } 100 } 101 102 103 /** 104 * Fetch a texel with the given partial derivatives to compute a level 105 * of detail in the mipmap. 106 * Called via machine->FetchTexelDeriv() 107 * \param lodBias the lod bias which may be specified by a TXB instruction, 108 * otherwise zero. 109 */ 110 static void 111 fetch_texel_deriv( struct gl_context *ctx, const GLfloat texcoord[4], 112 const GLfloat texdx[4], const GLfloat texdy[4], 113 GLfloat lodBias, GLuint unit, GLfloat color[4] ) 114 { 115 SWcontext *swrast = SWRAST_CONTEXT(ctx); 116 const struct gl_texture_unit *texUnit = &ctx->Texture.Unit[unit]; 117 const struct gl_texture_object *texObj = texUnit->_Current; 118 119 if (texObj) { 120 const struct gl_texture_image *texImg = _mesa_base_tex_image(texObj); 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 161 init_machine(struct gl_context *ctx, struct gl_program_machine *machine, 162 const struct gl_program *program, const SWspan *span, GLuint col) 163 { 164 GLfloat *wpos = span->array->attribs[VARYING_SLOT_POS][col]; 165 166 /* ARB_fragment_coord_conventions */ 167 if (program->OriginUpperLeft) 168 wpos[1] = ctx->DrawBuffer->Height - 1 - wpos[1]; 169 if (!program->PixelCenterInteger) { 170 wpos[0] += 0.5F; 171 wpos[1] += 0.5F; 172 } 173 174 /* Setup pointer to input attributes */ 175 machine->Attribs = span->array->attribs; 176 177 machine->DerivX = (GLfloat (*)[4]) span->attrStepX; 178 machine->DerivY = (GLfloat (*)[4]) span->attrStepY; 179 machine->NumDeriv = VARYING_SLOT_MAX; 180 181 machine->Samplers = program->SamplerUnits; 182 183 /* if running a GLSL program (not ARB_fragment_program) */ 184 if (ctx->_Shader->CurrentProgram[MESA_SHADER_FRAGMENT]) { 185 /* Store front/back facing value */ 186 machine->Attribs[VARYING_SLOT_FACE][col][0] = 1.0F - span->facing; 187 } 188 189 machine->CurElement = col; 190 191 /* init call stack */ 192 machine->StackDepth = 0; 193 194 machine->FetchTexelLod = fetch_texel_lod; 195 machine->FetchTexelDeriv = fetch_texel_deriv; 196 } 197 198 199 /** 200 * Run fragment program on the pixels in span from 'start' to 'end' - 1. 201 */ 202 static void 203 run_program(struct gl_context *ctx, SWspan *span, GLuint start, GLuint end) 204 { 205 SWcontext *swrast = SWRAST_CONTEXT(ctx); 206 const struct gl_program *program = ctx->FragmentProgram._Current; 207 const GLbitfield64 outputsWritten = program->info.outputs_written; 208 struct gl_program_machine *machine = &swrast->FragProgMachine; 209 GLuint i; 210 211 for (i = start; i < end; i++) { 212 if (span->array->mask[i]) { 213 init_machine(ctx, machine, program, span, i); 214 215 if (_mesa_execute_program(ctx, program, machine)) { 216 217 /* Store result color */ 218 if (outputsWritten & BITFIELD64_BIT(FRAG_RESULT_COLOR)) { 219 COPY_4V(span->array->attribs[VARYING_SLOT_COL0][i], 220 machine->Outputs[FRAG_RESULT_COLOR]); 221 } 222 else { 223 /* Multiple drawbuffers / render targets 224 * Note that colors beyond 0 and 1 will overwrite other 225 * attributes, such as FOGC, TEX0, TEX1, etc. That's OK. 226 */ 227 GLuint buf; 228 for (buf = 0; buf < ctx->DrawBuffer->_NumColorDrawBuffers; buf++) { 229 if (outputsWritten & BITFIELD64_BIT(FRAG_RESULT_DATA0 + buf)) { 230 COPY_4V(span->array->attribs[VARYING_SLOT_COL0 + buf][i], 231 machine->Outputs[FRAG_RESULT_DATA0 + buf]); 232 } 233 } 234 } 235 236 /* Store result depth/z */ 237 if (outputsWritten & BITFIELD64_BIT(FRAG_RESULT_DEPTH)) { 238 const GLfloat depth = machine->Outputs[FRAG_RESULT_DEPTH][2]; 239 if (depth <= 0.0F) 240 span->array->z[i] = 0; 241 else if (depth >= 1.0F) 242 span->array->z[i] = ctx->DrawBuffer->_DepthMax; 243 else 244 span->array->z[i] = 245 (GLuint) (depth * ctx->DrawBuffer->_DepthMaxF + 0.5F); 246 } 247 } 248 else { 249 /* killed fragment */ 250 span->array->mask[i] = GL_FALSE; 251 span->writeAll = GL_FALSE; 252 } 253 } 254 } 255 } 256 257 258 /** 259 * Execute the current fragment program for all the fragments 260 * in the given span. 261 */ 262 void 263 _swrast_exec_fragment_program( struct gl_context *ctx, SWspan *span ) 264 { 265 const struct gl_program *program = ctx->FragmentProgram._Current; 266 267 /* incoming colors should be floats */ 268 if (program->info.inputs_read & VARYING_BIT_COL0) { 269 assert(span->array->ChanType == GL_FLOAT); 270 } 271 272 run_program(ctx, span, 0, span->end); 273 274 if (program->info.outputs_written & BITFIELD64_BIT(FRAG_RESULT_COLOR)) { 275 span->interpMask &= ~SPAN_RGBA; 276 span->arrayMask |= SPAN_RGBA; 277 } 278 279 if (program->info.outputs_written & BITFIELD64_BIT(FRAG_RESULT_DEPTH)) { 280 span->interpMask &= ~SPAN_Z; 281 span->arrayMask |= SPAN_Z; 282 } 283 } 284 285