1/* 2 * Mesa 3-D graphics library 3 * 4 * Copyright (C) 1999-2008 Brian Paul All Rights Reserved. 5 * Copyright (C) 2009 VMware, Inc. 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 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR 21 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, 22 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR 23 * OTHER DEALINGS IN THE SOFTWARE. 24 */ 25 26 27/** 28 * \file swrast/s_span.c 29 * \brief Span processing functions used by all rasterization functions. 30 * This is where all the per-fragment tests are performed 31 * \author Brian Paul 32 */ 33 34#include "c99_math.h" 35#include "main/errors.h" 36#include "main/glheader.h" 37#include "main/format_pack.h" 38#include "main/format_unpack.h" 39#include "main/macros.h" 40#include "main/imports.h" 41#include "main/image.h" 42#include "main/samplerobj.h" 43#include "main/state.h" 44#include "main/stencil.h" 45#include "main/teximage.h" 46 47#include "s_atifragshader.h" 48#include "s_alpha.h" 49#include "s_blend.h" 50#include "s_context.h" 51#include "s_depth.h" 52#include "s_fog.h" 53#include "s_logic.h" 54#include "s_masking.h" 55#include "s_fragprog.h" 56#include "s_span.h" 57#include "s_stencil.h" 58#include "s_texcombine.h" 59 60#include <stdbool.h> 61 62/** 63 * Set default fragment attributes for the span using the 64 * current raster values. Used prior to glDraw/CopyPixels 65 * and glBitmap. 66 */ 67void 68_swrast_span_default_attribs(struct gl_context *ctx, SWspan *span) 69{ 70 GLchan r, g, b, a; 71 /* Z*/ 72 { 73 const GLfloat depthMax = ctx->DrawBuffer->_DepthMaxF; 74 if (ctx->DrawBuffer->Visual.depthBits <= 16) 75 span->z = FloatToFixed(ctx->Current.RasterPos[2] * depthMax + 0.5F); 76 else { 77 GLfloat tmpf = ctx->Current.RasterPos[2] * depthMax; 78 tmpf = MIN2(tmpf, depthMax); 79 span->z = (GLint)tmpf; 80 } 81 span->zStep = 0; 82 span->interpMask |= SPAN_Z; 83 } 84 85 /* W (for perspective correction) */ 86 span->attrStart[VARYING_SLOT_POS][3] = 1.0; 87 span->attrStepX[VARYING_SLOT_POS][3] = 0.0; 88 span->attrStepY[VARYING_SLOT_POS][3] = 0.0; 89 90 /* primary color, or color index */ 91 UNCLAMPED_FLOAT_TO_CHAN(r, ctx->Current.RasterColor[0]); 92 UNCLAMPED_FLOAT_TO_CHAN(g, ctx->Current.RasterColor[1]); 93 UNCLAMPED_FLOAT_TO_CHAN(b, ctx->Current.RasterColor[2]); 94 UNCLAMPED_FLOAT_TO_CHAN(a, ctx->Current.RasterColor[3]); 95#if CHAN_TYPE == GL_FLOAT 96 span->red = r; 97 span->green = g; 98 span->blue = b; 99 span->alpha = a; 100#else 101 span->red = IntToFixed(r); 102 span->green = IntToFixed(g); 103 span->blue = IntToFixed(b); 104 span->alpha = IntToFixed(a); 105#endif 106 span->redStep = 0; 107 span->greenStep = 0; 108 span->blueStep = 0; 109 span->alphaStep = 0; 110 span->interpMask |= SPAN_RGBA; 111 112 COPY_4V(span->attrStart[VARYING_SLOT_COL0], ctx->Current.RasterColor); 113 ASSIGN_4V(span->attrStepX[VARYING_SLOT_COL0], 0.0, 0.0, 0.0, 0.0); 114 ASSIGN_4V(span->attrStepY[VARYING_SLOT_COL0], 0.0, 0.0, 0.0, 0.0); 115 116 /* Secondary color */ 117 if (ctx->Light.Enabled || ctx->Fog.ColorSumEnabled) 118 { 119 COPY_4V(span->attrStart[VARYING_SLOT_COL1], ctx->Current.RasterSecondaryColor); 120 ASSIGN_4V(span->attrStepX[VARYING_SLOT_COL1], 0.0, 0.0, 0.0, 0.0); 121 ASSIGN_4V(span->attrStepY[VARYING_SLOT_COL1], 0.0, 0.0, 0.0, 0.0); 122 } 123 124 /* fog */ 125 { 126 const SWcontext *swrast = SWRAST_CONTEXT(ctx); 127 GLfloat fogVal; /* a coord or a blend factor */ 128 if (swrast->_PreferPixelFog) { 129 /* fog blend factors will be computed from fog coordinates per pixel */ 130 fogVal = ctx->Current.RasterDistance; 131 } 132 else { 133 /* fog blend factor should be computed from fogcoord now */ 134 fogVal = _swrast_z_to_fogfactor(ctx, ctx->Current.RasterDistance); 135 } 136 span->attrStart[VARYING_SLOT_FOGC][0] = fogVal; 137 span->attrStepX[VARYING_SLOT_FOGC][0] = 0.0; 138 span->attrStepY[VARYING_SLOT_FOGC][0] = 0.0; 139 } 140 141 /* texcoords */ 142 { 143 GLuint i; 144 for (i = 0; i < ctx->Const.MaxTextureCoordUnits; i++) { 145 const GLuint attr = VARYING_SLOT_TEX0 + i; 146 const GLfloat *tc = ctx->Current.RasterTexCoords[i]; 147 if (_swrast_use_fragment_program(ctx) || 148 _mesa_ati_fragment_shader_enabled(ctx)) { 149 COPY_4V(span->attrStart[attr], tc); 150 } 151 else if (tc[3] > 0.0F) { 152 /* use (s/q, t/q, r/q, 1) */ 153 span->attrStart[attr][0] = tc[0] / tc[3]; 154 span->attrStart[attr][1] = tc[1] / tc[3]; 155 span->attrStart[attr][2] = tc[2] / tc[3]; 156 span->attrStart[attr][3] = 1.0; 157 } 158 else { 159 ASSIGN_4V(span->attrStart[attr], 0.0F, 0.0F, 0.0F, 1.0F); 160 } 161 ASSIGN_4V(span->attrStepX[attr], 0.0F, 0.0F, 0.0F, 0.0F); 162 ASSIGN_4V(span->attrStepY[attr], 0.0F, 0.0F, 0.0F, 0.0F); 163 } 164 } 165} 166 167 168/** 169 * Interpolate the active attributes (and'd with attrMask) to 170 * fill in span->array->attribs[]. 171 * Perspective correction will be done. The point/line/triangle function 172 * should have computed attrStart/Step values for VARYING_SLOT_POS[3]! 173 */ 174static inline void 175interpolate_active_attribs(struct gl_context *ctx, SWspan *span, 176 GLbitfield64 attrMask) 177{ 178 const SWcontext *swrast = SWRAST_CONTEXT(ctx); 179 180 /* 181 * Don't overwrite existing array values, such as colors that may have 182 * been produced by glDraw/CopyPixels. 183 */ 184 attrMask &= ~span->arrayAttribs; 185 186 ATTRIB_LOOP_BEGIN 187 if (attrMask & BITFIELD64_BIT(attr)) { 188 const GLfloat dwdx = span->attrStepX[VARYING_SLOT_POS][3]; 189 GLfloat w = span->attrStart[VARYING_SLOT_POS][3]; 190 const GLfloat dv0dx = span->attrStepX[attr][0]; 191 const GLfloat dv1dx = span->attrStepX[attr][1]; 192 const GLfloat dv2dx = span->attrStepX[attr][2]; 193 const GLfloat dv3dx = span->attrStepX[attr][3]; 194 GLfloat v0 = span->attrStart[attr][0] + span->leftClip * dv0dx; 195 GLfloat v1 = span->attrStart[attr][1] + span->leftClip * dv1dx; 196 GLfloat v2 = span->attrStart[attr][2] + span->leftClip * dv2dx; 197 GLfloat v3 = span->attrStart[attr][3] + span->leftClip * dv3dx; 198 GLuint k; 199 for (k = 0; k < span->end; k++) { 200 const GLfloat invW = 1.0f / w; 201 span->array->attribs[attr][k][0] = v0 * invW; 202 span->array->attribs[attr][k][1] = v1 * invW; 203 span->array->attribs[attr][k][2] = v2 * invW; 204 span->array->attribs[attr][k][3] = v3 * invW; 205 v0 += dv0dx; 206 v1 += dv1dx; 207 v2 += dv2dx; 208 v3 += dv3dx; 209 w += dwdx; 210 } 211 assert((span->arrayAttribs & BITFIELD64_BIT(attr)) == 0); 212 span->arrayAttribs |= BITFIELD64_BIT(attr); 213 } 214 ATTRIB_LOOP_END 215} 216 217 218/** 219 * Interpolate primary colors to fill in the span->array->rgba8 (or rgb16) 220 * color array. 221 */ 222static inline void 223interpolate_int_colors(struct gl_context *ctx, SWspan *span) 224{ 225#if CHAN_BITS != 32 226 const GLuint n = span->end; 227 GLuint i; 228 229 assert(!(span->arrayMask & SPAN_RGBA)); 230#endif 231 232 switch (span->array->ChanType) { 233#if CHAN_BITS != 32 234 case GL_UNSIGNED_BYTE: 235 { 236 GLubyte (*rgba)[4] = span->array->rgba8; 237 if (span->interpMask & SPAN_FLAT) { 238 GLubyte color[4]; 239 color[RCOMP] = FixedToInt(span->red); 240 color[GCOMP] = FixedToInt(span->green); 241 color[BCOMP] = FixedToInt(span->blue); 242 color[ACOMP] = FixedToInt(span->alpha); 243 for (i = 0; i < n; i++) { 244 COPY_4UBV(rgba[i], color); 245 } 246 } 247 else { 248 GLfixed r = span->red; 249 GLfixed g = span->green; 250 GLfixed b = span->blue; 251 GLfixed a = span->alpha; 252 GLint dr = span->redStep; 253 GLint dg = span->greenStep; 254 GLint db = span->blueStep; 255 GLint da = span->alphaStep; 256 for (i = 0; i < n; i++) { 257 rgba[i][RCOMP] = FixedToChan(r); 258 rgba[i][GCOMP] = FixedToChan(g); 259 rgba[i][BCOMP] = FixedToChan(b); 260 rgba[i][ACOMP] = FixedToChan(a); 261 r += dr; 262 g += dg; 263 b += db; 264 a += da; 265 } 266 } 267 } 268 break; 269 case GL_UNSIGNED_SHORT: 270 { 271 GLushort (*rgba)[4] = span->array->rgba16; 272 if (span->interpMask & SPAN_FLAT) { 273 GLushort color[4]; 274 color[RCOMP] = FixedToInt(span->red); 275 color[GCOMP] = FixedToInt(span->green); 276 color[BCOMP] = FixedToInt(span->blue); 277 color[ACOMP] = FixedToInt(span->alpha); 278 for (i = 0; i < n; i++) { 279 COPY_4V(rgba[i], color); 280 } 281 } 282 else { 283 GLushort (*rgba)[4] = span->array->rgba16; 284 GLfixed r, g, b, a; 285 GLint dr, dg, db, da; 286 r = span->red; 287 g = span->green; 288 b = span->blue; 289 a = span->alpha; 290 dr = span->redStep; 291 dg = span->greenStep; 292 db = span->blueStep; 293 da = span->alphaStep; 294 for (i = 0; i < n; i++) { 295 rgba[i][RCOMP] = FixedToChan(r); 296 rgba[i][GCOMP] = FixedToChan(g); 297 rgba[i][BCOMP] = FixedToChan(b); 298 rgba[i][ACOMP] = FixedToChan(a); 299 r += dr; 300 g += dg; 301 b += db; 302 a += da; 303 } 304 } 305 } 306 break; 307#endif 308 case GL_FLOAT: 309 interpolate_active_attribs(ctx, span, VARYING_BIT_COL0); 310 break; 311 default: 312 _mesa_problem(ctx, "bad datatype 0x%x in interpolate_int_colors", 313 span->array->ChanType); 314 } 315 span->arrayMask |= SPAN_RGBA; 316} 317 318 319/** 320 * Populate the VARYING_SLOT_COL0 array. 321 */ 322static inline void 323interpolate_float_colors(SWspan *span) 324{ 325 GLfloat (*col0)[4] = span->array->attribs[VARYING_SLOT_COL0]; 326 const GLuint n = span->end; 327 GLuint i; 328 329 assert(!(span->arrayAttribs & VARYING_BIT_COL0)); 330 331 if (span->arrayMask & SPAN_RGBA) { 332 /* convert array of int colors */ 333 for (i = 0; i < n; i++) { 334 col0[i][0] = UBYTE_TO_FLOAT(span->array->rgba8[i][0]); 335 col0[i][1] = UBYTE_TO_FLOAT(span->array->rgba8[i][1]); 336 col0[i][2] = UBYTE_TO_FLOAT(span->array->rgba8[i][2]); 337 col0[i][3] = UBYTE_TO_FLOAT(span->array->rgba8[i][3]); 338 } 339 } 340 else { 341 /* interpolate red/green/blue/alpha to get float colors */ 342 assert(span->interpMask & SPAN_RGBA); 343 if (span->interpMask & SPAN_FLAT) { 344 GLfloat r = FixedToFloat(span->red); 345 GLfloat g = FixedToFloat(span->green); 346 GLfloat b = FixedToFloat(span->blue); 347 GLfloat a = FixedToFloat(span->alpha); 348 for (i = 0; i < n; i++) { 349 ASSIGN_4V(col0[i], r, g, b, a); 350 } 351 } 352 else { 353 GLfloat r = FixedToFloat(span->red); 354 GLfloat g = FixedToFloat(span->green); 355 GLfloat b = FixedToFloat(span->blue); 356 GLfloat a = FixedToFloat(span->alpha); 357 GLfloat dr = FixedToFloat(span->redStep); 358 GLfloat dg = FixedToFloat(span->greenStep); 359 GLfloat db = FixedToFloat(span->blueStep); 360 GLfloat da = FixedToFloat(span->alphaStep); 361 for (i = 0; i < n; i++) { 362 col0[i][0] = r; 363 col0[i][1] = g; 364 col0[i][2] = b; 365 col0[i][3] = a; 366 r += dr; 367 g += dg; 368 b += db; 369 a += da; 370 } 371 } 372 } 373 374 span->arrayAttribs |= VARYING_BIT_COL0; 375 span->array->ChanType = GL_FLOAT; 376} 377 378 379 380/** 381 * Fill in the span.zArray array from the span->z, zStep values. 382 */ 383void 384_swrast_span_interpolate_z( const struct gl_context *ctx, SWspan *span ) 385{ 386 const GLuint n = span->end; 387 GLuint i; 388 389 assert(!(span->arrayMask & SPAN_Z)); 390 391 if (ctx->DrawBuffer->Visual.depthBits <= 16) { 392 GLfixed zval = span->z; 393 GLuint *z = span->array->z; 394 for (i = 0; i < n; i++) { 395 z[i] = FixedToInt(zval); 396 zval += span->zStep; 397 } 398 } 399 else { 400 /* Deep Z buffer, no fixed->int shift */ 401 GLuint zval = span->z; 402 GLuint *z = span->array->z; 403 for (i = 0; i < n; i++) { 404 z[i] = zval; 405 zval += span->zStep; 406 } 407 } 408 span->interpMask &= ~SPAN_Z; 409 span->arrayMask |= SPAN_Z; 410} 411 412 413/** 414 * Compute mipmap LOD from partial derivatives. 415 * This the ideal solution, as given in the OpenGL spec. 416 */ 417GLfloat 418_swrast_compute_lambda(GLfloat dsdx, GLfloat dsdy, GLfloat dtdx, GLfloat dtdy, 419 GLfloat dqdx, GLfloat dqdy, GLfloat texW, GLfloat texH, 420 GLfloat s, GLfloat t, GLfloat q, GLfloat invQ) 421{ 422 GLfloat dudx = texW * ((s + dsdx) / (q + dqdx) - s * invQ); 423 GLfloat dvdx = texH * ((t + dtdx) / (q + dqdx) - t * invQ); 424 GLfloat dudy = texW * ((s + dsdy) / (q + dqdy) - s * invQ); 425 GLfloat dvdy = texH * ((t + dtdy) / (q + dqdy) - t * invQ); 426 GLfloat x = sqrtf(dudx * dudx + dvdx * dvdx); 427 GLfloat y = sqrtf(dudy * dudy + dvdy * dvdy); 428 GLfloat rho = MAX2(x, y); 429 GLfloat lambda = LOG2(rho); 430 return lambda; 431} 432 433 434/** 435 * Compute mipmap LOD from partial derivatives. 436 * This is a faster approximation than above function. 437 */ 438#if 0 439GLfloat 440_swrast_compute_lambda(GLfloat dsdx, GLfloat dsdy, GLfloat dtdx, GLfloat dtdy, 441 GLfloat dqdx, GLfloat dqdy, GLfloat texW, GLfloat texH, 442 GLfloat s, GLfloat t, GLfloat q, GLfloat invQ) 443{ 444 GLfloat dsdx2 = (s + dsdx) / (q + dqdx) - s * invQ; 445 GLfloat dtdx2 = (t + dtdx) / (q + dqdx) - t * invQ; 446 GLfloat dsdy2 = (s + dsdy) / (q + dqdy) - s * invQ; 447 GLfloat dtdy2 = (t + dtdy) / (q + dqdy) - t * invQ; 448 GLfloat maxU, maxV, rho, lambda; 449 dsdx2 = fabsf(dsdx2); 450 dsdy2 = fabsf(dsdy2); 451 dtdx2 = fabsf(dtdx2); 452 dtdy2 = fabsf(dtdy2); 453 maxU = MAX2(dsdx2, dsdy2) * texW; 454 maxV = MAX2(dtdx2, dtdy2) * texH; 455 rho = MAX2(maxU, maxV); 456 lambda = LOG2(rho); 457 return lambda; 458} 459#endif 460 461 462/** 463 * Fill in the span.array->attrib[VARYING_SLOT_TEXn] arrays from the 464 * using the attrStart/Step values. 465 * 466 * This function only used during fixed-function fragment processing. 467 * 468 * Note: in the places where we divide by Q (or mult by invQ) we're 469 * really doing two things: perspective correction and texcoord 470 * projection. Remember, for texcoord (s,t,r,q) we need to index 471 * texels with (s/q, t/q, r/q). 472 */ 473static void 474interpolate_texcoords(struct gl_context *ctx, SWspan *span) 475{ 476 const GLuint maxUnit 477 = (ctx->Texture._EnabledCoordUnits > 1) ? ctx->Const.MaxTextureUnits : 1; 478 GLuint u; 479 480 /* XXX CoordUnits vs. ImageUnits */ 481 for (u = 0; u < maxUnit; u++) { 482 if (ctx->Texture._EnabledCoordUnits & (1 << u)) { 483 const GLuint attr = VARYING_SLOT_TEX0 + u; 484 const struct gl_texture_object *obj = ctx->Texture.Unit[u]._Current; 485 GLfloat texW, texH; 486 GLboolean needLambda; 487 GLfloat (*texcoord)[4] = span->array->attribs[attr]; 488 GLfloat *lambda = span->array->lambda[u]; 489 const GLfloat dsdx = span->attrStepX[attr][0]; 490 const GLfloat dsdy = span->attrStepY[attr][0]; 491 const GLfloat dtdx = span->attrStepX[attr][1]; 492 const GLfloat dtdy = span->attrStepY[attr][1]; 493 const GLfloat drdx = span->attrStepX[attr][2]; 494 const GLfloat dqdx = span->attrStepX[attr][3]; 495 const GLfloat dqdy = span->attrStepY[attr][3]; 496 GLfloat s = span->attrStart[attr][0] + span->leftClip * dsdx; 497 GLfloat t = span->attrStart[attr][1] + span->leftClip * dtdx; 498 GLfloat r = span->attrStart[attr][2] + span->leftClip * drdx; 499 GLfloat q = span->attrStart[attr][3] + span->leftClip * dqdx; 500 501 if (obj) { 502 const struct gl_texture_image *img = _mesa_base_tex_image(obj); 503 const struct swrast_texture_image *swImg = 504 swrast_texture_image_const(img); 505 const struct gl_sampler_object *samp = _mesa_get_samplerobj(ctx, u); 506 507 needLambda = (samp->MinFilter != samp->MagFilter) 508 || _swrast_use_fragment_program(ctx); 509 /* LOD is calculated directly in the ansiotropic filter, we can 510 * skip the normal lambda function as the result is ignored. 511 */ 512 if (samp->MaxAnisotropy > 1.0F && 513 samp->MinFilter == GL_LINEAR_MIPMAP_LINEAR) { 514 needLambda = GL_FALSE; 515 } 516 texW = swImg->WidthScale; 517 texH = swImg->HeightScale; 518 } 519 else { 520 /* using a fragment program */ 521 texW = 1.0; 522 texH = 1.0; 523 needLambda = GL_FALSE; 524 } 525 526 if (needLambda) { 527 GLuint i; 528 if (_swrast_use_fragment_program(ctx) 529 || _mesa_ati_fragment_shader_enabled(ctx)) { 530 /* do perspective correction but don't divide s, t, r by q */ 531 const GLfloat dwdx = span->attrStepX[VARYING_SLOT_POS][3]; 532 GLfloat w = span->attrStart[VARYING_SLOT_POS][3] + span->leftClip * dwdx; 533 for (i = 0; i < span->end; i++) { 534 const GLfloat invW = 1.0F / w; 535 texcoord[i][0] = s * invW; 536 texcoord[i][1] = t * invW; 537 texcoord[i][2] = r * invW; 538 texcoord[i][3] = q * invW; 539 lambda[i] = _swrast_compute_lambda(dsdx, dsdy, dtdx, dtdy, 540 dqdx, dqdy, texW, texH, 541 s, t, q, invW); 542 s += dsdx; 543 t += dtdx; 544 r += drdx; 545 q += dqdx; 546 w += dwdx; 547 } 548 } 549 else { 550 for (i = 0; i < span->end; i++) { 551 const GLfloat invQ = (q == 0.0F) ? 1.0F : (1.0F / q); 552 texcoord[i][0] = s * invQ; 553 texcoord[i][1] = t * invQ; 554 texcoord[i][2] = r * invQ; 555 texcoord[i][3] = q; 556 lambda[i] = _swrast_compute_lambda(dsdx, dsdy, dtdx, dtdy, 557 dqdx, dqdy, texW, texH, 558 s, t, q, invQ); 559 s += dsdx; 560 t += dtdx; 561 r += drdx; 562 q += dqdx; 563 } 564 } 565 span->arrayMask |= SPAN_LAMBDA; 566 } 567 else { 568 GLuint i; 569 if (_swrast_use_fragment_program(ctx) || 570 _mesa_ati_fragment_shader_enabled(ctx)) { 571 /* do perspective correction but don't divide s, t, r by q */ 572 const GLfloat dwdx = span->attrStepX[VARYING_SLOT_POS][3]; 573 GLfloat w = span->attrStart[VARYING_SLOT_POS][3] + span->leftClip * dwdx; 574 for (i = 0; i < span->end; i++) { 575 const GLfloat invW = 1.0F / w; 576 texcoord[i][0] = s * invW; 577 texcoord[i][1] = t * invW; 578 texcoord[i][2] = r * invW; 579 texcoord[i][3] = q * invW; 580 lambda[i] = 0.0; 581 s += dsdx; 582 t += dtdx; 583 r += drdx; 584 q += dqdx; 585 w += dwdx; 586 } 587 } 588 else if (dqdx == 0.0F) { 589 /* Ortho projection or polygon's parallel to window X axis */ 590 const GLfloat invQ = (q == 0.0F) ? 1.0F : (1.0F / q); 591 for (i = 0; i < span->end; i++) { 592 texcoord[i][0] = s * invQ; 593 texcoord[i][1] = t * invQ; 594 texcoord[i][2] = r * invQ; 595 texcoord[i][3] = q; 596 lambda[i] = 0.0; 597 s += dsdx; 598 t += dtdx; 599 r += drdx; 600 } 601 } 602 else { 603 for (i = 0; i < span->end; i++) { 604 const GLfloat invQ = (q == 0.0F) ? 1.0F : (1.0F / q); 605 texcoord[i][0] = s * invQ; 606 texcoord[i][1] = t * invQ; 607 texcoord[i][2] = r * invQ; 608 texcoord[i][3] = q; 609 lambda[i] = 0.0; 610 s += dsdx; 611 t += dtdx; 612 r += drdx; 613 q += dqdx; 614 } 615 } 616 } /* lambda */ 617 } /* if */ 618 } /* for */ 619} 620 621 622/** 623 * Fill in the arrays->attribs[VARYING_SLOT_POS] array. 624 */ 625static inline void 626interpolate_wpos(struct gl_context *ctx, SWspan *span) 627{ 628 GLfloat (*wpos)[4] = span->array->attribs[VARYING_SLOT_POS]; 629 GLuint i; 630 const GLfloat zScale = 1.0F / ctx->DrawBuffer->_DepthMaxF; 631 GLfloat w, dw; 632 633 if (span->arrayMask & SPAN_XY) { 634 for (i = 0; i < span->end; i++) { 635 wpos[i][0] = (GLfloat) span->array->x[i]; 636 wpos[i][1] = (GLfloat) span->array->y[i]; 637 } 638 } 639 else { 640 for (i = 0; i < span->end; i++) { 641 wpos[i][0] = (GLfloat) span->x + i; 642 wpos[i][1] = (GLfloat) span->y; 643 } 644 } 645 646 dw = span->attrStepX[VARYING_SLOT_POS][3]; 647 w = span->attrStart[VARYING_SLOT_POS][3] + span->leftClip * dw; 648 for (i = 0; i < span->end; i++) { 649 wpos[i][2] = (GLfloat) span->array->z[i] * zScale; 650 wpos[i][3] = w; 651 w += dw; 652 } 653} 654 655 656/** 657 * Apply the current polygon stipple pattern to a span of pixels. 658 */ 659static inline void 660stipple_polygon_span(struct gl_context *ctx, SWspan *span) 661{ 662 GLubyte *mask = span->array->mask; 663 664 assert(ctx->Polygon.StippleFlag); 665 666 if (span->arrayMask & SPAN_XY) { 667 /* arrays of x/y pixel coords */ 668 GLuint i; 669 for (i = 0; i < span->end; i++) { 670 const GLint col = span->array->x[i] % 32; 671 const GLint row = span->array->y[i] % 32; 672 const GLuint stipple = ctx->PolygonStipple[row]; 673 if (((1 << col) & stipple) == 0) { 674 mask[i] = 0; 675 } 676 } 677 } 678 else { 679 /* horizontal span of pixels */ 680 const GLuint highBit = 1 << 31; 681 const GLuint stipple = ctx->PolygonStipple[span->y % 32]; 682 GLuint i, m = highBit >> (GLuint) (span->x % 32); 683 for (i = 0; i < span->end; i++) { 684 if ((m & stipple) == 0) { 685 mask[i] = 0; 686 } 687 m = m >> 1; 688 if (m == 0) { 689 m = highBit; 690 } 691 } 692 } 693 span->writeAll = GL_FALSE; 694} 695 696 697/** 698 * Clip a pixel span to the current buffer/window boundaries: 699 * DrawBuffer->_Xmin, _Xmax, _Ymin, _Ymax. This will accomplish 700 * window clipping and scissoring. 701 * Return: GL_TRUE some pixels still visible 702 * GL_FALSE nothing visible 703 */ 704static inline GLuint 705clip_span( struct gl_context *ctx, SWspan *span ) 706{ 707 const GLint xmin = ctx->DrawBuffer->_Xmin; 708 const GLint xmax = ctx->DrawBuffer->_Xmax; 709 const GLint ymin = ctx->DrawBuffer->_Ymin; 710 const GLint ymax = ctx->DrawBuffer->_Ymax; 711 712 span->leftClip = 0; 713 714 if (span->arrayMask & SPAN_XY) { 715 /* arrays of x/y pixel coords */ 716 const GLint *x = span->array->x; 717 const GLint *y = span->array->y; 718 const GLint n = span->end; 719 GLubyte *mask = span->array->mask; 720 GLint i; 721 GLuint passed = 0; 722 if (span->arrayMask & SPAN_MASK) { 723 /* note: using & intead of && to reduce branches */ 724 for (i = 0; i < n; i++) { 725 mask[i] &= (x[i] >= xmin) & (x[i] < xmax) 726 & (y[i] >= ymin) & (y[i] < ymax); 727 passed += mask[i]; 728 } 729 } 730 else { 731 /* note: using & intead of && to reduce branches */ 732 for (i = 0; i < n; i++) { 733 mask[i] = (x[i] >= xmin) & (x[i] < xmax) 734 & (y[i] >= ymin) & (y[i] < ymax); 735 passed += mask[i]; 736 } 737 } 738 return passed > 0; 739 } 740 else { 741 /* horizontal span of pixels */ 742 const GLint x = span->x; 743 const GLint y = span->y; 744 GLint n = span->end; 745 746 /* Trivial rejection tests */ 747 if (y < ymin || y >= ymax || x + n <= xmin || x >= xmax) { 748 span->end = 0; 749 return GL_FALSE; /* all pixels clipped */ 750 } 751 752 /* Clip to right */ 753 if (x + n > xmax) { 754 assert(x < xmax); 755 n = span->end = xmax - x; 756 } 757 758 /* Clip to the left */ 759 if (x < xmin) { 760 const GLint leftClip = xmin - x; 761 GLuint i; 762 763 assert(leftClip > 0); 764 assert(x + n > xmin); 765 766 /* Clip 'leftClip' pixels from the left side. 767 * The span->leftClip field will be applied when we interpolate 768 * fragment attributes. 769 * For arrays of values, shift them left. 770 */ 771 for (i = 0; i < VARYING_SLOT_MAX; i++) { 772 if (span->interpMask & (1u << i)) { 773 GLuint j; 774 for (j = 0; j < 4; j++) { 775 span->attrStart[i][j] += leftClip * span->attrStepX[i][j]; 776 } 777 } 778 } 779 780 span->red += leftClip * span->redStep; 781 span->green += leftClip * span->greenStep; 782 span->blue += leftClip * span->blueStep; 783 span->alpha += leftClip * span->alphaStep; 784 span->index += leftClip * span->indexStep; 785 span->z += leftClip * span->zStep; 786 span->intTex[0] += leftClip * span->intTexStep[0]; 787 span->intTex[1] += leftClip * span->intTexStep[1]; 788 789#define SHIFT_ARRAY(ARRAY, SHIFT, LEN) \ 790 memmove(ARRAY, ARRAY + (SHIFT), (LEN) * sizeof(ARRAY[0])) 791 792 for (i = 0; i < VARYING_SLOT_MAX; i++) { 793 if (span->arrayAttribs & BITFIELD64_BIT(i)) { 794 /* shift array elements left by 'leftClip' */ 795 SHIFT_ARRAY(span->array->attribs[i], leftClip, n - leftClip); 796 } 797 } 798 799 SHIFT_ARRAY(span->array->mask, leftClip, n - leftClip); 800 SHIFT_ARRAY(span->array->rgba8, leftClip, n - leftClip); 801 SHIFT_ARRAY(span->array->rgba16, leftClip, n - leftClip); 802 SHIFT_ARRAY(span->array->x, leftClip, n - leftClip); 803 SHIFT_ARRAY(span->array->y, leftClip, n - leftClip); 804 SHIFT_ARRAY(span->array->z, leftClip, n - leftClip); 805 SHIFT_ARRAY(span->array->index, leftClip, n - leftClip); 806 for (i = 0; i < MAX_TEXTURE_COORD_UNITS; i++) { 807 SHIFT_ARRAY(span->array->lambda[i], leftClip, n - leftClip); 808 } 809 SHIFT_ARRAY(span->array->coverage, leftClip, n - leftClip); 810 811#undef SHIFT_ARRAY 812 813 span->leftClip = leftClip; 814 span->x = xmin; 815 span->end -= leftClip; 816 span->writeAll = GL_FALSE; 817 } 818 819 assert(span->x >= xmin); 820 assert(span->x + span->end <= xmax); 821 assert(span->y >= ymin); 822 assert(span->y < ymax); 823 824 return GL_TRUE; /* some pixels visible */ 825 } 826} 827 828 829/** 830 * Add specular colors to primary colors. 831 * Only called during fixed-function operation. 832 * Result is float color array (VARYING_SLOT_COL0). 833 */ 834static inline void 835add_specular(struct gl_context *ctx, SWspan *span) 836{ 837 const SWcontext *swrast = SWRAST_CONTEXT(ctx); 838 const GLubyte *mask = span->array->mask; 839 GLfloat (*col0)[4] = span->array->attribs[VARYING_SLOT_COL0]; 840 GLfloat (*col1)[4] = span->array->attribs[VARYING_SLOT_COL1]; 841 GLuint i; 842 843 assert(!_swrast_use_fragment_program(ctx)); 844 assert(span->arrayMask & SPAN_RGBA); 845 assert(swrast->_ActiveAttribMask & VARYING_BIT_COL1); 846 (void) swrast; /* silence warning */ 847 848 if (span->array->ChanType == GL_FLOAT) { 849 if ((span->arrayAttribs & VARYING_BIT_COL0) == 0) { 850 interpolate_active_attribs(ctx, span, VARYING_BIT_COL0); 851 } 852 } 853 else { 854 /* need float colors */ 855 if ((span->arrayAttribs & VARYING_BIT_COL0) == 0) { 856 interpolate_float_colors(span); 857 } 858 } 859 860 if ((span->arrayAttribs & VARYING_BIT_COL1) == 0) { 861 /* XXX could avoid this and interpolate COL1 in the loop below */ 862 interpolate_active_attribs(ctx, span, VARYING_BIT_COL1); 863 } 864 865 assert(span->arrayAttribs & VARYING_BIT_COL0); 866 assert(span->arrayAttribs & VARYING_BIT_COL1); 867 868 for (i = 0; i < span->end; i++) { 869 if (mask[i]) { 870 col0[i][0] += col1[i][0]; 871 col0[i][1] += col1[i][1]; 872 col0[i][2] += col1[i][2]; 873 } 874 } 875 876 span->array->ChanType = GL_FLOAT; 877} 878 879 880/** 881 * Apply antialiasing coverage value to alpha values. 882 */ 883static inline void 884apply_aa_coverage(SWspan *span) 885{ 886 const GLfloat *coverage = span->array->coverage; 887 GLuint i; 888 if (span->array->ChanType == GL_UNSIGNED_BYTE) { 889 GLubyte (*rgba)[4] = span->array->rgba8; 890 for (i = 0; i < span->end; i++) { 891 const GLfloat a = rgba[i][ACOMP] * coverage[i]; 892 rgba[i][ACOMP] = (GLubyte) CLAMP(a, 0.0F, 255.0F); 893 assert(coverage[i] >= 0.0F); 894 assert(coverage[i] <= 1.0F); 895 } 896 } 897 else if (span->array->ChanType == GL_UNSIGNED_SHORT) { 898 GLushort (*rgba)[4] = span->array->rgba16; 899 for (i = 0; i < span->end; i++) { 900 const GLfloat a = rgba[i][ACOMP] * coverage[i]; 901 rgba[i][ACOMP] = (GLushort) CLAMP(a, 0.0F, 65535.0F); 902 } 903 } 904 else { 905 GLfloat (*rgba)[4] = span->array->attribs[VARYING_SLOT_COL0]; 906 for (i = 0; i < span->end; i++) { 907 rgba[i][ACOMP] = rgba[i][ACOMP] * coverage[i]; 908 /* clamp later */ 909 } 910 } 911} 912 913 914/** 915 * Clamp span's float colors to [0,1] 916 */ 917static inline void 918clamp_colors(SWspan *span) 919{ 920 GLfloat (*rgba)[4] = span->array->attribs[VARYING_SLOT_COL0]; 921 GLuint i; 922 assert(span->array->ChanType == GL_FLOAT); 923 for (i = 0; i < span->end; i++) { 924 rgba[i][RCOMP] = CLAMP(rgba[i][RCOMP], 0.0F, 1.0F); 925 rgba[i][GCOMP] = CLAMP(rgba[i][GCOMP], 0.0F, 1.0F); 926 rgba[i][BCOMP] = CLAMP(rgba[i][BCOMP], 0.0F, 1.0F); 927 rgba[i][ACOMP] = CLAMP(rgba[i][ACOMP], 0.0F, 1.0F); 928 } 929} 930 931 932/** 933 * Convert the span's color arrays to the given type. 934 * The only way 'output' can be greater than zero is when we have a fragment 935 * program that writes to gl_FragData[1] or higher. 936 * \param output which fragment program color output is being processed 937 */ 938static inline void 939convert_color_type(SWspan *span, GLenum srcType, GLenum newType, GLuint output) 940{ 941 GLvoid *src, *dst; 942 943 if (output > 0 || srcType == GL_FLOAT) { 944 src = span->array->attribs[VARYING_SLOT_COL0 + output]; 945 span->array->ChanType = GL_FLOAT; 946 } 947 else if (srcType == GL_UNSIGNED_BYTE) { 948 src = span->array->rgba8; 949 } 950 else { 951 assert(srcType == GL_UNSIGNED_SHORT); 952 src = span->array->rgba16; 953 } 954 955 if (newType == GL_UNSIGNED_BYTE) { 956 dst = span->array->rgba8; 957 } 958 else if (newType == GL_UNSIGNED_SHORT) { 959 dst = span->array->rgba16; 960 } 961 else { 962 dst = span->array->attribs[VARYING_SLOT_COL0]; 963 } 964 965 _mesa_convert_colors(span->array->ChanType, src, 966 newType, dst, 967 span->end, span->array->mask); 968 969 span->array->ChanType = newType; 970 span->array->rgba = dst; 971} 972 973 974 975/** 976 * Apply fragment shader, fragment program or normal texturing to span. 977 */ 978static inline void 979shade_texture_span(struct gl_context *ctx, SWspan *span) 980{ 981 if (_swrast_use_fragment_program(ctx) || 982 _mesa_ati_fragment_shader_enabled(ctx)) { 983 /* programmable shading */ 984 if (span->primitive == GL_BITMAP && span->array->ChanType != GL_FLOAT) { 985 convert_color_type(span, span->array->ChanType, GL_FLOAT, 0); 986 } 987 else { 988 span->array->rgba = (void *) span->array->attribs[VARYING_SLOT_COL0]; 989 } 990 991 if (span->primitive != GL_POINT || 992 (span->interpMask & SPAN_RGBA) || 993 ctx->Point.PointSprite) { 994 /* for single-pixel points, we populated the arrays already */ 995 interpolate_active_attribs(ctx, span, ~0); 996 } 997 span->array->ChanType = GL_FLOAT; 998 999 if (!(span->arrayMask & SPAN_Z)) 1000 _swrast_span_interpolate_z (ctx, span); 1001 1002#if 0 1003 if (inputsRead & VARYING_BIT_POS) 1004#else 1005 /* XXX always interpolate wpos so that DDX/DDY work */ 1006#endif 1007 interpolate_wpos(ctx, span); 1008 1009 /* Run fragment program/shader now */ 1010 if (_swrast_use_fragment_program(ctx)) { 1011 _swrast_exec_fragment_program(ctx, span); 1012 } 1013 else { 1014 assert(_mesa_ati_fragment_shader_enabled(ctx)); 1015 _swrast_exec_fragment_shader(ctx, span); 1016 } 1017 } 1018 else if (ctx->Texture._EnabledCoordUnits) { 1019 /* conventional texturing */ 1020 1021#if CHAN_BITS == 32 1022 if ((span->arrayAttribs & VARYING_BIT_COL0) == 0) { 1023 interpolate_int_colors(ctx, span); 1024 } 1025#else 1026 if (!(span->arrayMask & SPAN_RGBA)) 1027 interpolate_int_colors(ctx, span); 1028#endif 1029 if ((span->arrayAttribs & VARYING_BITS_TEX_ANY) == 0x0) 1030 interpolate_texcoords(ctx, span); 1031 1032 _swrast_texture_span(ctx, span); 1033 } 1034} 1035 1036 1037/** Put colors at x/y locations into a renderbuffer */ 1038static void 1039put_values(struct gl_context *ctx, struct gl_renderbuffer *rb, 1040 GLenum datatype, 1041 GLuint count, const GLint x[], const GLint y[], 1042 const void *values, const GLubyte *mask) 1043{ 1044 gl_pack_ubyte_rgba_func pack_ubyte = NULL; 1045 gl_pack_float_rgba_func pack_float = NULL; 1046 GLuint i; 1047 1048 if (datatype == GL_UNSIGNED_BYTE) 1049 pack_ubyte = _mesa_get_pack_ubyte_rgba_function(rb->Format); 1050 else 1051 pack_float = _mesa_get_pack_float_rgba_function(rb->Format); 1052 1053 for (i = 0; i < count; i++) { 1054 if (mask[i]) { 1055 GLubyte *dst = _swrast_pixel_address(rb, x[i], y[i]); 1056 1057 if (datatype == GL_UNSIGNED_BYTE) { 1058 pack_ubyte((const GLubyte *) values + 4 * i, dst); 1059 } 1060 else { 1061 assert(datatype == GL_FLOAT); 1062 pack_float((const GLfloat *) values + 4 * i, dst); 1063 } 1064 } 1065 } 1066} 1067 1068 1069/** Put row of colors into renderbuffer */ 1070void 1071_swrast_put_row(struct gl_context *ctx, struct gl_renderbuffer *rb, 1072 GLenum datatype, 1073 GLuint count, GLint x, GLint y, 1074 const void *values, const GLubyte *mask) 1075{ 1076 GLubyte *dst = _swrast_pixel_address(rb, x, y); 1077 1078 if (!mask) { 1079 if (datatype == GL_UNSIGNED_BYTE) { 1080 _mesa_pack_ubyte_rgba_row(rb->Format, count, 1081 (const GLubyte (*)[4]) values, dst); 1082 } 1083 else { 1084 assert(datatype == GL_FLOAT); 1085 _mesa_pack_float_rgba_row(rb->Format, count, 1086 (const GLfloat (*)[4]) values, dst); 1087 } 1088 } 1089 else { 1090 const GLuint bpp = _mesa_get_format_bytes(rb->Format); 1091 GLuint i, runLen, runStart; 1092 /* We can't pass a 'mask' array to the _mesa_pack_rgba_row() functions 1093 * so look for runs where mask=1... 1094 */ 1095 runLen = runStart = 0; 1096 for (i = 0; i < count; i++) { 1097 if (mask[i]) { 1098 if (runLen == 0) 1099 runStart = i; 1100 runLen++; 1101 } 1102 1103 if (!mask[i] || i == count - 1) { 1104 /* might be the end of a run of pixels */ 1105 if (runLen > 0) { 1106 if (datatype == GL_UNSIGNED_BYTE) { 1107 _mesa_pack_ubyte_rgba_row(rb->Format, runLen, 1108 (const GLubyte (*)[4]) values + runStart, 1109 dst + runStart * bpp); 1110 } 1111 else { 1112 assert(datatype == GL_FLOAT); 1113 _mesa_pack_float_rgba_row(rb->Format, runLen, 1114 (const GLfloat (*)[4]) values + runStart, 1115 dst + runStart * bpp); 1116 } 1117 runLen = 0; 1118 } 1119 } 1120 } 1121 } 1122} 1123 1124 1125 1126/** 1127 * Apply all the per-fragment operations to a span. 1128 * This now includes texturing (_swrast_write_texture_span() is history). 1129 * This function may modify any of the array values in the span. 1130 * span->interpMask and span->arrayMask may be changed but will be restored 1131 * to their original values before returning. 1132 */ 1133void 1134_swrast_write_rgba_span( struct gl_context *ctx, SWspan *span) 1135{ 1136 const SWcontext *swrast = SWRAST_CONTEXT(ctx); 1137 const GLbitfield origInterpMask = span->interpMask; 1138 const GLbitfield origArrayMask = span->arrayMask; 1139 const GLbitfield64 origArrayAttribs = span->arrayAttribs; 1140 const GLenum origChanType = span->array->ChanType; 1141 void * const origRgba = span->array->rgba; 1142 const GLboolean shader = (_swrast_use_fragment_program(ctx) 1143 || _mesa_ati_fragment_shader_enabled(ctx)); 1144 const GLboolean shaderOrTexture = shader || ctx->Texture._EnabledCoordUnits; 1145 struct gl_framebuffer *fb = ctx->DrawBuffer; 1146 1147 /* 1148 printf("%s() interp 0x%x array 0x%x\n", __func__, 1149 span->interpMask, span->arrayMask); 1150 */ 1151 1152 assert(span->primitive == GL_POINT || 1153 span->primitive == GL_LINE || 1154 span->primitive == GL_POLYGON || 1155 span->primitive == GL_BITMAP); 1156 1157 /* Fragment write masks */ 1158 if (span->arrayMask & SPAN_MASK) { 1159 /* mask was initialized by caller, probably glBitmap */ 1160 span->writeAll = GL_FALSE; 1161 } 1162 else { 1163 memset(span->array->mask, 1, span->end); 1164 span->writeAll = GL_TRUE; 1165 } 1166 1167 /* Clip to window/scissor box */ 1168 if (!clip_span(ctx, span)) { 1169 return; 1170 } 1171 1172 assert(span->end <= SWRAST_MAX_WIDTH); 1173 1174 /* Depth bounds test */ 1175 if (ctx->Depth.BoundsTest && fb->Visual.depthBits > 0) { 1176 if (!_swrast_depth_bounds_test(ctx, span)) { 1177 return; 1178 } 1179 } 1180 1181#ifdef DEBUG 1182 /* Make sure all fragments are within window bounds */ 1183 if (span->arrayMask & SPAN_XY) { 1184 /* array of pixel locations */ 1185 GLuint i; 1186 for (i = 0; i < span->end; i++) { 1187 if (span->array->mask[i]) { 1188 assert(span->array->x[i] >= fb->_Xmin); 1189 assert(span->array->x[i] < fb->_Xmax); 1190 assert(span->array->y[i] >= fb->_Ymin); 1191 assert(span->array->y[i] < fb->_Ymax); 1192 } 1193 } 1194 } 1195#endif 1196 1197 /* Polygon Stippling */ 1198 if (ctx->Polygon.StippleFlag && span->primitive == GL_POLYGON) { 1199 stipple_polygon_span(ctx, span); 1200 } 1201 1202 /* This is the normal place to compute the fragment color/Z 1203 * from texturing or shading. 1204 */ 1205 if (shaderOrTexture && !swrast->_DeferredTexture) { 1206 shade_texture_span(ctx, span); 1207 } 1208 1209 /* Do the alpha test */ 1210 if (ctx->Color.AlphaEnabled) { 1211 if (!_swrast_alpha_test(ctx, span)) { 1212 /* all fragments failed test */ 1213 goto end; 1214 } 1215 } 1216 1217 /* Stencil and Z testing */ 1218 if (_mesa_stencil_is_enabled(ctx) || ctx->Depth.Test) { 1219 if (!(span->arrayMask & SPAN_Z)) 1220 _swrast_span_interpolate_z(ctx, span); 1221 1222 if (ctx->Transform.DepthClampNear && ctx->Transform.DepthClampFar) 1223 _swrast_depth_clamp_span(ctx, span); 1224 1225 if (_mesa_stencil_is_enabled(ctx)) { 1226 /* Combined Z/stencil tests */ 1227 if (!_swrast_stencil_and_ztest_span(ctx, span)) { 1228 /* all fragments failed test */ 1229 goto end; 1230 } 1231 } 1232 else if (fb->Visual.depthBits > 0) { 1233 /* Just regular depth testing */ 1234 assert(ctx->Depth.Test); 1235 assert(span->arrayMask & SPAN_Z); 1236 if (!_swrast_depth_test_span(ctx, span)) { 1237 /* all fragments failed test */ 1238 goto end; 1239 } 1240 } 1241 } 1242 1243 if (ctx->Query.CurrentOcclusionObject) { 1244 /* update count of 'passed' fragments */ 1245 struct gl_query_object *q = ctx->Query.CurrentOcclusionObject; 1246 GLuint i; 1247 for (i = 0; i < span->end; i++) 1248 q->Result += span->array->mask[i]; 1249 } 1250 1251 /* We had to wait until now to check for glColorMask(0,0,0,0) because of 1252 * the occlusion test. 1253 */ 1254 if (fb->_NumColorDrawBuffers == 1 && 1255 !GET_COLORMASK(ctx->Color.ColorMask, 0)) { 1256 /* no colors to write */ 1257 goto end; 1258 } 1259 1260 /* If we were able to defer fragment color computation to now, there's 1261 * a good chance that many fragments will have already been killed by 1262 * Z/stencil testing. 1263 */ 1264 if (shaderOrTexture && swrast->_DeferredTexture) { 1265 shade_texture_span(ctx, span); 1266 } 1267 1268#if CHAN_BITS == 32 1269 if ((span->arrayAttribs & VARYING_BIT_COL0) == 0) { 1270 interpolate_active_attribs(ctx, span, VARYING_BIT_COL0); 1271 } 1272#else 1273 if ((span->arrayMask & SPAN_RGBA) == 0) { 1274 interpolate_int_colors(ctx, span); 1275 } 1276#endif 1277 1278 assert(span->arrayMask & SPAN_RGBA); 1279 1280 if (span->primitive == GL_BITMAP || !swrast->SpecularVertexAdd) { 1281 /* Add primary and specular (diffuse + specular) colors */ 1282 if (!shader) { 1283 if (ctx->Fog.ColorSumEnabled || 1284 (ctx->Light.Enabled && 1285 ctx->Light.Model.ColorControl == GL_SEPARATE_SPECULAR_COLOR)) { 1286 add_specular(ctx, span); 1287 } 1288 } 1289 } 1290 1291 /* Fog */ 1292 if (swrast->_FogEnabled) { 1293 _swrast_fog_rgba_span(ctx, span); 1294 } 1295 1296 /* Antialias coverage application */ 1297 if (span->arrayMask & SPAN_COVERAGE) { 1298 apply_aa_coverage(span); 1299 } 1300 1301 /* Clamp color/alpha values over the range [0.0, 1.0] before storage */ 1302 if (ctx->Color.ClampFragmentColor == GL_TRUE && 1303 span->array->ChanType == GL_FLOAT) { 1304 clamp_colors(span); 1305 } 1306 1307 /* 1308 * Write to renderbuffers. 1309 * Depending on glDrawBuffer() state and the which color outputs are 1310 * written by the fragment shader, we may either replicate one color to 1311 * all renderbuffers or write a different color to each renderbuffer. 1312 * multiFragOutputs=TRUE for the later case. 1313 */ 1314 { 1315 const GLuint numBuffers = fb->_NumColorDrawBuffers; 1316 const struct gl_program *fp = ctx->FragmentProgram._Current; 1317 const GLboolean multiFragOutputs = 1318 _swrast_use_fragment_program(ctx) 1319 && fp->info.outputs_written >= (1 << FRAG_RESULT_DATA0); 1320 /* Save srcColorType because convert_color_type() can change it */ 1321 const GLenum srcColorType = span->array->ChanType; 1322 GLuint buf; 1323 1324 for (buf = 0; buf < numBuffers; buf++) { 1325 struct gl_renderbuffer *rb = fb->_ColorDrawBuffers[buf]; 1326 1327 /* color[fragOutput] will be written to buffer[buf] */ 1328 1329 if (rb) { 1330 /* re-use one of the attribute array buffers for rgbaSave */ 1331 GLchan (*rgbaSave)[4] = (GLchan (*)[4]) span->array->attribs[0]; 1332 struct swrast_renderbuffer *srb = swrast_renderbuffer(rb); 1333 const GLenum dstColorType = srb->ColorType; 1334 1335 assert(dstColorType == GL_UNSIGNED_BYTE || 1336 dstColorType == GL_FLOAT); 1337 1338 /* set span->array->rgba to colors for renderbuffer's datatype */ 1339 if (srcColorType != dstColorType) { 1340 convert_color_type(span, srcColorType, dstColorType, 1341 multiFragOutputs ? buf : 0); 1342 } 1343 else { 1344 if (srcColorType == GL_UNSIGNED_BYTE) { 1345 span->array->rgba = span->array->rgba8; 1346 } 1347 else { 1348 span->array->rgba = (void *) 1349 span->array->attribs[VARYING_SLOT_COL0]; 1350 } 1351 } 1352 1353 if (!multiFragOutputs && numBuffers > 1) { 1354 /* save colors for second, third renderbuffer writes */ 1355 memcpy(rgbaSave, span->array->rgba, 1356 4 * span->end * sizeof(GLchan)); 1357 } 1358 1359 assert(rb->_BaseFormat == GL_RGBA || 1360 rb->_BaseFormat == GL_RGB || 1361 rb->_BaseFormat == GL_RED || 1362 rb->_BaseFormat == GL_RG || 1363 rb->_BaseFormat == GL_ALPHA); 1364 1365 if (ctx->Color.ColorLogicOpEnabled) { 1366 _swrast_logicop_rgba_span(ctx, rb, span); 1367 } 1368 else if ((ctx->Color.BlendEnabled >> buf) & 1) { 1369 _swrast_blend_span(ctx, rb, span); 1370 } 1371 1372 if (GET_COLORMASK(ctx->Color.ColorMask, buf) != 0xf) { 1373 _swrast_mask_rgba_span(ctx, rb, span, buf); 1374 } 1375 1376 if (span->arrayMask & SPAN_XY) { 1377 /* array of pixel coords */ 1378 put_values(ctx, rb, 1379 span->array->ChanType, span->end, 1380 span->array->x, span->array->y, 1381 span->array->rgba, span->array->mask); 1382 } 1383 else { 1384 /* horizontal run of pixels */ 1385 _swrast_put_row(ctx, rb, 1386 span->array->ChanType, 1387 span->end, span->x, span->y, 1388 span->array->rgba, 1389 span->writeAll ? NULL: span->array->mask); 1390 } 1391 1392 if (!multiFragOutputs && numBuffers > 1) { 1393 /* restore original span values */ 1394 memcpy(span->array->rgba, rgbaSave, 1395 4 * span->end * sizeof(GLchan)); 1396 } 1397 1398 } /* if rb */ 1399 } /* for buf */ 1400 } 1401 1402end: 1403 /* restore these values before returning */ 1404 span->interpMask = origInterpMask; 1405 span->arrayMask = origArrayMask; 1406 span->arrayAttribs = origArrayAttribs; 1407 span->array->ChanType = origChanType; 1408 span->array->rgba = origRgba; 1409} 1410 1411 1412/** 1413 * Read float RGBA pixels from a renderbuffer. Clipping will be done to 1414 * prevent reading ouside the buffer's boundaries. 1415 * \param rgba the returned colors 1416 */ 1417void 1418_swrast_read_rgba_span( struct gl_context *ctx, struct gl_renderbuffer *rb, 1419 GLuint n, GLint x, GLint y, 1420 GLvoid *rgba) 1421{ 1422 struct swrast_renderbuffer *srb = swrast_renderbuffer(rb); 1423 GLenum dstType = GL_FLOAT; 1424 const GLint bufWidth = (GLint) rb->Width; 1425 const GLint bufHeight = (GLint) rb->Height; 1426 1427 if (y < 0 || y >= bufHeight || x + (GLint) n < 0 || x >= bufWidth) { 1428 /* completely above, below, or right */ 1429 /* XXX maybe leave rgba values undefined? */ 1430 memset(rgba, 0, 4 * n * sizeof(GLchan)); 1431 } 1432 else { 1433 GLint skip, length; 1434 GLubyte *src; 1435 1436 if (x < 0) { 1437 /* left edge clipping */ 1438 skip = -x; 1439 length = (GLint) n - skip; 1440 if (length < 0) { 1441 /* completely left of window */ 1442 return; 1443 } 1444 if (length > bufWidth) { 1445 length = bufWidth; 1446 } 1447 } 1448 else if ((GLint) (x + n) > bufWidth) { 1449 /* right edge clipping */ 1450 skip = 0; 1451 length = bufWidth - x; 1452 if (length < 0) { 1453 /* completely to right of window */ 1454 return; 1455 } 1456 } 1457 else { 1458 /* no clipping */ 1459 skip = 0; 1460 length = (GLint) n; 1461 } 1462 1463 assert(rb); 1464 assert(rb->_BaseFormat == GL_RGBA || 1465 rb->_BaseFormat == GL_RGB || 1466 rb->_BaseFormat == GL_RG || 1467 rb->_BaseFormat == GL_RED || 1468 rb->_BaseFormat == GL_LUMINANCE || 1469 rb->_BaseFormat == GL_INTENSITY || 1470 rb->_BaseFormat == GL_LUMINANCE_ALPHA || 1471 rb->_BaseFormat == GL_ALPHA); 1472 1473 assert(srb->Map); 1474 (void) srb; /* silence unused var warning */ 1475 1476 src = _swrast_pixel_address(rb, x + skip, y); 1477 1478 if (dstType == GL_UNSIGNED_BYTE) { 1479 _mesa_unpack_ubyte_rgba_row(rb->Format, length, src, 1480 (GLubyte (*)[4]) rgba + skip); 1481 } 1482 else if (dstType == GL_FLOAT) { 1483 _mesa_unpack_rgba_row(rb->Format, length, src, 1484 (GLfloat (*)[4]) rgba + skip); 1485 } 1486 else { 1487 _mesa_problem(ctx, "unexpected type in _swrast_read_rgba_span()"); 1488 } 1489 } 1490} 1491 1492 1493/** 1494 * Get colors at x/y positions with clipping. 1495 * \param type type of values to return 1496 */ 1497static void 1498get_values(struct gl_context *ctx, struct gl_renderbuffer *rb, 1499 GLuint count, const GLint x[], const GLint y[], 1500 void *values, GLenum type) 1501{ 1502 GLuint i; 1503 1504 for (i = 0; i < count; i++) { 1505 if (x[i] >= 0 && y[i] >= 0 && 1506 x[i] < (GLint) rb->Width && y[i] < (GLint) rb->Height) { 1507 /* inside */ 1508 const GLubyte *src = _swrast_pixel_address(rb, x[i], y[i]); 1509 1510 if (type == GL_UNSIGNED_BYTE) { 1511 _mesa_unpack_ubyte_rgba_row(rb->Format, 1, src, 1512 (GLubyte (*)[4]) values + i); 1513 } 1514 else if (type == GL_FLOAT) { 1515 _mesa_unpack_rgba_row(rb->Format, 1, src, 1516 (GLfloat (*)[4]) values + i); 1517 } 1518 else { 1519 _mesa_problem(ctx, "unexpected type in get_values()"); 1520 } 1521 } 1522 } 1523} 1524 1525 1526/** 1527 * Get row of colors with clipping. 1528 * \param type type of values to return 1529 */ 1530static void 1531get_row(struct gl_context *ctx, struct gl_renderbuffer *rb, 1532 GLuint count, GLint x, GLint y, 1533 GLvoid *values, GLenum type) 1534{ 1535 GLint skip = 0; 1536 GLubyte *src; 1537 1538 if (y < 0 || y >= (GLint) rb->Height) 1539 return; /* above or below */ 1540 1541 if (x + (GLint) count <= 0 || x >= (GLint) rb->Width) 1542 return; /* entirely left or right */ 1543 1544 if (x + count > rb->Width) { 1545 /* right clip */ 1546 GLint clip = x + count - rb->Width; 1547 count -= clip; 1548 } 1549 1550 if (x < 0) { 1551 /* left clip */ 1552 skip = -x; 1553 x = 0; 1554 count -= skip; 1555 } 1556 1557 src = _swrast_pixel_address(rb, x, y); 1558 1559 if (type == GL_UNSIGNED_BYTE) { 1560 _mesa_unpack_ubyte_rgba_row(rb->Format, count, src, 1561 (GLubyte (*)[4]) values + skip); 1562 } 1563 else if (type == GL_FLOAT) { 1564 _mesa_unpack_rgba_row(rb->Format, count, src, 1565 (GLfloat (*)[4]) values + skip); 1566 } 1567 else { 1568 _mesa_problem(ctx, "unexpected type in get_row()"); 1569 } 1570} 1571 1572 1573/** 1574 * Get RGBA pixels from the given renderbuffer. 1575 * Used by blending, logicop and masking functions. 1576 * \return pointer to the colors we read. 1577 */ 1578void * 1579_swrast_get_dest_rgba(struct gl_context *ctx, struct gl_renderbuffer *rb, 1580 SWspan *span) 1581{ 1582 void *rbPixels; 1583 1584 /* Point rbPixels to a temporary space */ 1585 rbPixels = span->array->attribs[VARYING_SLOT_MAX - 1]; 1586 1587 /* Get destination values from renderbuffer */ 1588 if (span->arrayMask & SPAN_XY) { 1589 get_values(ctx, rb, span->end, span->array->x, span->array->y, 1590 rbPixels, span->array->ChanType); 1591 } 1592 else { 1593 get_row(ctx, rb, span->end, span->x, span->y, 1594 rbPixels, span->array->ChanType); 1595 } 1596 1597 return rbPixels; 1598} 1599