1 /* 2 * Mesa 3-D graphics library 3 * Version: 7.5 4 * 5 * Copyright (C) 1999-2008 Brian Paul All Rights Reserved. 6 * Copyright (C) 2009 VMware, Inc. All Rights Reserved. 7 * 8 * Permission is hereby granted, free of charge, to any person obtaining a 9 * copy of this software and associated documentation files (the "Software"), 10 * to deal in the Software without restriction, including without limitation 11 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 12 * and/or sell copies of the Software, and to permit persons to whom the 13 * Software is furnished to do so, subject to the following conditions: 14 * 15 * The above copyright notice and this permission notice shall be included 16 * in all copies or substantial portions of the Software. 17 * 18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS 19 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 20 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 21 * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN 22 * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 23 * CONNECTION WITH THE SOFTWARE OR THE USE OR 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 "main/glheader.h" 35 #include "main/colormac.h" 36 #include "main/format_pack.h" 37 #include "main/format_unpack.h" 38 #include "main/macros.h" 39 #include "main/imports.h" 40 #include "main/image.h" 41 #include "main/samplerobj.h" 42 43 #include "s_atifragshader.h" 44 #include "s_alpha.h" 45 #include "s_blend.h" 46 #include "s_context.h" 47 #include "s_depth.h" 48 #include "s_fog.h" 49 #include "s_logic.h" 50 #include "s_masking.h" 51 #include "s_fragprog.h" 52 #include "s_span.h" 53 #include "s_stencil.h" 54 #include "s_texcombine.h" 55 56 #include <stdbool.h> 57 58 /** 59 * Set default fragment attributes for the span using the 60 * current raster values. Used prior to glDraw/CopyPixels 61 * and glBitmap. 62 */ 63 void 64 _swrast_span_default_attribs(struct gl_context *ctx, SWspan *span) 65 { 66 GLchan r, g, b, a; 67 /* Z*/ 68 { 69 const GLfloat depthMax = ctx->DrawBuffer->_DepthMaxF; 70 if (ctx->DrawBuffer->Visual.depthBits <= 16) 71 span->z = FloatToFixed(ctx->Current.RasterPos[2] * depthMax + 0.5F); 72 else { 73 GLfloat tmpf = ctx->Current.RasterPos[2] * depthMax; 74 tmpf = MIN2(tmpf, depthMax); 75 span->z = (GLint)tmpf; 76 } 77 span->zStep = 0; 78 span->interpMask |= SPAN_Z; 79 } 80 81 /* W (for perspective correction) */ 82 span->attrStart[FRAG_ATTRIB_WPOS][3] = 1.0; 83 span->attrStepX[FRAG_ATTRIB_WPOS][3] = 0.0; 84 span->attrStepY[FRAG_ATTRIB_WPOS][3] = 0.0; 85 86 /* primary color, or color index */ 87 UNCLAMPED_FLOAT_TO_CHAN(r, ctx->Current.RasterColor[0]); 88 UNCLAMPED_FLOAT_TO_CHAN(g, ctx->Current.RasterColor[1]); 89 UNCLAMPED_FLOAT_TO_CHAN(b, ctx->Current.RasterColor[2]); 90 UNCLAMPED_FLOAT_TO_CHAN(a, ctx->Current.RasterColor[3]); 91 #if CHAN_TYPE == GL_FLOAT 92 span->red = r; 93 span->green = g; 94 span->blue = b; 95 span->alpha = a; 96 #else 97 span->red = IntToFixed(r); 98 span->green = IntToFixed(g); 99 span->blue = IntToFixed(b); 100 span->alpha = IntToFixed(a); 101 #endif 102 span->redStep = 0; 103 span->greenStep = 0; 104 span->blueStep = 0; 105 span->alphaStep = 0; 106 span->interpMask |= SPAN_RGBA; 107 108 COPY_4V(span->attrStart[FRAG_ATTRIB_COL0], ctx->Current.RasterColor); 109 ASSIGN_4V(span->attrStepX[FRAG_ATTRIB_COL0], 0.0, 0.0, 0.0, 0.0); 110 ASSIGN_4V(span->attrStepY[FRAG_ATTRIB_COL0], 0.0, 0.0, 0.0, 0.0); 111 112 /* Secondary color */ 113 if (ctx->Light.Enabled || ctx->Fog.ColorSumEnabled) 114 { 115 COPY_4V(span->attrStart[FRAG_ATTRIB_COL1], ctx->Current.RasterSecondaryColor); 116 ASSIGN_4V(span->attrStepX[FRAG_ATTRIB_COL1], 0.0, 0.0, 0.0, 0.0); 117 ASSIGN_4V(span->attrStepY[FRAG_ATTRIB_COL1], 0.0, 0.0, 0.0, 0.0); 118 } 119 120 /* fog */ 121 { 122 const SWcontext *swrast = SWRAST_CONTEXT(ctx); 123 GLfloat fogVal; /* a coord or a blend factor */ 124 if (swrast->_PreferPixelFog) { 125 /* fog blend factors will be computed from fog coordinates per pixel */ 126 fogVal = ctx->Current.RasterDistance; 127 } 128 else { 129 /* fog blend factor should be computed from fogcoord now */ 130 fogVal = _swrast_z_to_fogfactor(ctx, ctx->Current.RasterDistance); 131 } 132 span->attrStart[FRAG_ATTRIB_FOGC][0] = fogVal; 133 span->attrStepX[FRAG_ATTRIB_FOGC][0] = 0.0; 134 span->attrStepY[FRAG_ATTRIB_FOGC][0] = 0.0; 135 } 136 137 /* texcoords */ 138 { 139 GLuint i; 140 for (i = 0; i < ctx->Const.MaxTextureCoordUnits; i++) { 141 const GLuint attr = FRAG_ATTRIB_TEX0 + i; 142 const GLfloat *tc = ctx->Current.RasterTexCoords[i]; 143 if (_swrast_use_fragment_program(ctx) || 144 ctx->ATIFragmentShader._Enabled) { 145 COPY_4V(span->attrStart[attr], tc); 146 } 147 else if (tc[3] > 0.0F) { 148 /* use (s/q, t/q, r/q, 1) */ 149 span->attrStart[attr][0] = tc[0] / tc[3]; 150 span->attrStart[attr][1] = tc[1] / tc[3]; 151 span->attrStart[attr][2] = tc[2] / tc[3]; 152 span->attrStart[attr][3] = 1.0; 153 } 154 else { 155 ASSIGN_4V(span->attrStart[attr], 0.0F, 0.0F, 0.0F, 1.0F); 156 } 157 ASSIGN_4V(span->attrStepX[attr], 0.0F, 0.0F, 0.0F, 0.0F); 158 ASSIGN_4V(span->attrStepY[attr], 0.0F, 0.0F, 0.0F, 0.0F); 159 } 160 } 161 } 162 163 164 /** 165 * Interpolate the active attributes (and'd with attrMask) to 166 * fill in span->array->attribs[]. 167 * Perspective correction will be done. The point/line/triangle function 168 * should have computed attrStart/Step values for FRAG_ATTRIB_WPOS[3]! 169 */ 170 static inline void 171 interpolate_active_attribs(struct gl_context *ctx, SWspan *span, 172 GLbitfield64 attrMask) 173 { 174 const SWcontext *swrast = SWRAST_CONTEXT(ctx); 175 176 /* 177 * Don't overwrite existing array values, such as colors that may have 178 * been produced by glDraw/CopyPixels. 179 */ 180 attrMask &= ~span->arrayAttribs; 181 182 ATTRIB_LOOP_BEGIN 183 if (attrMask & BITFIELD64_BIT(attr)) { 184 const GLfloat dwdx = span->attrStepX[FRAG_ATTRIB_WPOS][3]; 185 GLfloat w = span->attrStart[FRAG_ATTRIB_WPOS][3]; 186 const GLfloat dv0dx = span->attrStepX[attr][0]; 187 const GLfloat dv1dx = span->attrStepX[attr][1]; 188 const GLfloat dv2dx = span->attrStepX[attr][2]; 189 const GLfloat dv3dx = span->attrStepX[attr][3]; 190 GLfloat v0 = span->attrStart[attr][0] + span->leftClip * dv0dx; 191 GLfloat v1 = span->attrStart[attr][1] + span->leftClip * dv1dx; 192 GLfloat v2 = span->attrStart[attr][2] + span->leftClip * dv2dx; 193 GLfloat v3 = span->attrStart[attr][3] + span->leftClip * dv3dx; 194 GLuint k; 195 for (k = 0; k < span->end; k++) { 196 const GLfloat invW = 1.0f / w; 197 span->array->attribs[attr][k][0] = v0 * invW; 198 span->array->attribs[attr][k][1] = v1 * invW; 199 span->array->attribs[attr][k][2] = v2 * invW; 200 span->array->attribs[attr][k][3] = v3 * invW; 201 v0 += dv0dx; 202 v1 += dv1dx; 203 v2 += dv2dx; 204 v3 += dv3dx; 205 w += dwdx; 206 } 207 ASSERT((span->arrayAttribs & BITFIELD64_BIT(attr)) == 0); 208 span->arrayAttribs |= BITFIELD64_BIT(attr); 209 } 210 ATTRIB_LOOP_END 211 } 212 213 214 /** 215 * Interpolate primary colors to fill in the span->array->rgba8 (or rgb16) 216 * color array. 217 */ 218 static inline void 219 interpolate_int_colors(struct gl_context *ctx, SWspan *span) 220 { 221 #if CHAN_BITS != 32 222 const GLuint n = span->end; 223 GLuint i; 224 225 ASSERT(!(span->arrayMask & SPAN_RGBA)); 226 #endif 227 228 switch (span->array->ChanType) { 229 #if CHAN_BITS != 32 230 case GL_UNSIGNED_BYTE: 231 { 232 GLubyte (*rgba)[4] = span->array->rgba8; 233 if (span->interpMask & SPAN_FLAT) { 234 GLubyte color[4]; 235 color[RCOMP] = FixedToInt(span->red); 236 color[GCOMP] = FixedToInt(span->green); 237 color[BCOMP] = FixedToInt(span->blue); 238 color[ACOMP] = FixedToInt(span->alpha); 239 for (i = 0; i < n; i++) { 240 COPY_4UBV(rgba[i], color); 241 } 242 } 243 else { 244 GLfixed r = span->red; 245 GLfixed g = span->green; 246 GLfixed b = span->blue; 247 GLfixed a = span->alpha; 248 GLint dr = span->redStep; 249 GLint dg = span->greenStep; 250 GLint db = span->blueStep; 251 GLint da = span->alphaStep; 252 for (i = 0; i < n; i++) { 253 rgba[i][RCOMP] = FixedToChan(r); 254 rgba[i][GCOMP] = FixedToChan(g); 255 rgba[i][BCOMP] = FixedToChan(b); 256 rgba[i][ACOMP] = FixedToChan(a); 257 r += dr; 258 g += dg; 259 b += db; 260 a += da; 261 } 262 } 263 } 264 break; 265 case GL_UNSIGNED_SHORT: 266 { 267 GLushort (*rgba)[4] = span->array->rgba16; 268 if (span->interpMask & SPAN_FLAT) { 269 GLushort color[4]; 270 color[RCOMP] = FixedToInt(span->red); 271 color[GCOMP] = FixedToInt(span->green); 272 color[BCOMP] = FixedToInt(span->blue); 273 color[ACOMP] = FixedToInt(span->alpha); 274 for (i = 0; i < n; i++) { 275 COPY_4V(rgba[i], color); 276 } 277 } 278 else { 279 GLushort (*rgba)[4] = span->array->rgba16; 280 GLfixed r, g, b, a; 281 GLint dr, dg, db, da; 282 r = span->red; 283 g = span->green; 284 b = span->blue; 285 a = span->alpha; 286 dr = span->redStep; 287 dg = span->greenStep; 288 db = span->blueStep; 289 da = span->alphaStep; 290 for (i = 0; i < n; i++) { 291 rgba[i][RCOMP] = FixedToChan(r); 292 rgba[i][GCOMP] = FixedToChan(g); 293 rgba[i][BCOMP] = FixedToChan(b); 294 rgba[i][ACOMP] = FixedToChan(a); 295 r += dr; 296 g += dg; 297 b += db; 298 a += da; 299 } 300 } 301 } 302 break; 303 #endif 304 case GL_FLOAT: 305 interpolate_active_attribs(ctx, span, FRAG_BIT_COL0); 306 break; 307 default: 308 _mesa_problem(ctx, "bad datatype 0x%x in interpolate_int_colors", 309 span->array->ChanType); 310 } 311 span->arrayMask |= SPAN_RGBA; 312 } 313 314 315 /** 316 * Populate the FRAG_ATTRIB_COL0 array. 317 */ 318 static inline void 319 interpolate_float_colors(SWspan *span) 320 { 321 GLfloat (*col0)[4] = span->array->attribs[FRAG_ATTRIB_COL0]; 322 const GLuint n = span->end; 323 GLuint i; 324 325 assert(!(span->arrayAttribs & FRAG_BIT_COL0)); 326 327 if (span->arrayMask & SPAN_RGBA) { 328 /* convert array of int colors */ 329 for (i = 0; i < n; i++) { 330 col0[i][0] = UBYTE_TO_FLOAT(span->array->rgba8[i][0]); 331 col0[i][1] = UBYTE_TO_FLOAT(span->array->rgba8[i][1]); 332 col0[i][2] = UBYTE_TO_FLOAT(span->array->rgba8[i][2]); 333 col0[i][3] = UBYTE_TO_FLOAT(span->array->rgba8[i][3]); 334 } 335 } 336 else { 337 /* interpolate red/green/blue/alpha to get float colors */ 338 ASSERT(span->interpMask & SPAN_RGBA); 339 if (span->interpMask & SPAN_FLAT) { 340 GLfloat r = FixedToFloat(span->red); 341 GLfloat g = FixedToFloat(span->green); 342 GLfloat b = FixedToFloat(span->blue); 343 GLfloat a = FixedToFloat(span->alpha); 344 for (i = 0; i < n; i++) { 345 ASSIGN_4V(col0[i], r, g, b, a); 346 } 347 } 348 else { 349 GLfloat r = FixedToFloat(span->red); 350 GLfloat g = FixedToFloat(span->green); 351 GLfloat b = FixedToFloat(span->blue); 352 GLfloat a = FixedToFloat(span->alpha); 353 GLfloat dr = FixedToFloat(span->redStep); 354 GLfloat dg = FixedToFloat(span->greenStep); 355 GLfloat db = FixedToFloat(span->blueStep); 356 GLfloat da = FixedToFloat(span->alphaStep); 357 for (i = 0; i < n; i++) { 358 col0[i][0] = r; 359 col0[i][1] = g; 360 col0[i][2] = b; 361 col0[i][3] = a; 362 r += dr; 363 g += dg; 364 b += db; 365 a += da; 366 } 367 } 368 } 369 370 span->arrayAttribs |= FRAG_BIT_COL0; 371 span->array->ChanType = GL_FLOAT; 372 } 373 374 375 376 /** 377 * Fill in the span.zArray array from the span->z, zStep values. 378 */ 379 void 380 _swrast_span_interpolate_z( const struct gl_context *ctx, SWspan *span ) 381 { 382 const GLuint n = span->end; 383 GLuint i; 384 385 ASSERT(!(span->arrayMask & SPAN_Z)); 386 387 if (ctx->DrawBuffer->Visual.depthBits <= 16) { 388 GLfixed zval = span->z; 389 GLuint *z = span->array->z; 390 for (i = 0; i < n; i++) { 391 z[i] = FixedToInt(zval); 392 zval += span->zStep; 393 } 394 } 395 else { 396 /* Deep Z buffer, no fixed->int shift */ 397 GLuint zval = span->z; 398 GLuint *z = span->array->z; 399 for (i = 0; i < n; i++) { 400 z[i] = zval; 401 zval += span->zStep; 402 } 403 } 404 span->interpMask &= ~SPAN_Z; 405 span->arrayMask |= SPAN_Z; 406 } 407 408 409 /** 410 * Compute mipmap LOD from partial derivatives. 411 * This the ideal solution, as given in the OpenGL spec. 412 */ 413 GLfloat 414 _swrast_compute_lambda(GLfloat dsdx, GLfloat dsdy, GLfloat dtdx, GLfloat dtdy, 415 GLfloat dqdx, GLfloat dqdy, GLfloat texW, GLfloat texH, 416 GLfloat s, GLfloat t, GLfloat q, GLfloat invQ) 417 { 418 GLfloat dudx = texW * ((s + dsdx) / (q + dqdx) - s * invQ); 419 GLfloat dvdx = texH * ((t + dtdx) / (q + dqdx) - t * invQ); 420 GLfloat dudy = texW * ((s + dsdy) / (q + dqdy) - s * invQ); 421 GLfloat dvdy = texH * ((t + dtdy) / (q + dqdy) - t * invQ); 422 GLfloat x = SQRTF(dudx * dudx + dvdx * dvdx); 423 GLfloat y = SQRTF(dudy * dudy + dvdy * dvdy); 424 GLfloat rho = MAX2(x, y); 425 GLfloat lambda = LOG2(rho); 426 return lambda; 427 } 428 429 430 /** 431 * Compute mipmap LOD from partial derivatives. 432 * This is a faster approximation than above function. 433 */ 434 #if 0 435 GLfloat 436 _swrast_compute_lambda(GLfloat dsdx, GLfloat dsdy, GLfloat dtdx, GLfloat dtdy, 437 GLfloat dqdx, GLfloat dqdy, GLfloat texW, GLfloat texH, 438 GLfloat s, GLfloat t, GLfloat q, GLfloat invQ) 439 { 440 GLfloat dsdx2 = (s + dsdx) / (q + dqdx) - s * invQ; 441 GLfloat dtdx2 = (t + dtdx) / (q + dqdx) - t * invQ; 442 GLfloat dsdy2 = (s + dsdy) / (q + dqdy) - s * invQ; 443 GLfloat dtdy2 = (t + dtdy) / (q + dqdy) - t * invQ; 444 GLfloat maxU, maxV, rho, lambda; 445 dsdx2 = FABSF(dsdx2); 446 dsdy2 = FABSF(dsdy2); 447 dtdx2 = FABSF(dtdx2); 448 dtdy2 = FABSF(dtdy2); 449 maxU = MAX2(dsdx2, dsdy2) * texW; 450 maxV = MAX2(dtdx2, dtdy2) * texH; 451 rho = MAX2(maxU, maxV); 452 lambda = LOG2(rho); 453 return lambda; 454 } 455 #endif 456 457 458 /** 459 * Fill in the span.array->attrib[FRAG_ATTRIB_TEXn] arrays from the 460 * using the attrStart/Step values. 461 * 462 * This function only used during fixed-function fragment processing. 463 * 464 * Note: in the places where we divide by Q (or mult by invQ) we're 465 * really doing two things: perspective correction and texcoord 466 * projection. Remember, for texcoord (s,t,r,q) we need to index 467 * texels with (s/q, t/q, r/q). 468 */ 469 static void 470 interpolate_texcoords(struct gl_context *ctx, SWspan *span) 471 { 472 const GLuint maxUnit 473 = (ctx->Texture._EnabledCoordUnits > 1) ? ctx->Const.MaxTextureUnits : 1; 474 GLuint u; 475 476 /* XXX CoordUnits vs. ImageUnits */ 477 for (u = 0; u < maxUnit; u++) { 478 if (ctx->Texture._EnabledCoordUnits & (1 << u)) { 479 const GLuint attr = FRAG_ATTRIB_TEX0 + u; 480 const struct gl_texture_object *obj = ctx->Texture.Unit[u]._Current; 481 GLfloat texW, texH; 482 GLboolean needLambda; 483 GLfloat (*texcoord)[4] = span->array->attribs[attr]; 484 GLfloat *lambda = span->array->lambda[u]; 485 const GLfloat dsdx = span->attrStepX[attr][0]; 486 const GLfloat dsdy = span->attrStepY[attr][0]; 487 const GLfloat dtdx = span->attrStepX[attr][1]; 488 const GLfloat dtdy = span->attrStepY[attr][1]; 489 const GLfloat drdx = span->attrStepX[attr][2]; 490 const GLfloat dqdx = span->attrStepX[attr][3]; 491 const GLfloat dqdy = span->attrStepY[attr][3]; 492 GLfloat s = span->attrStart[attr][0] + span->leftClip * dsdx; 493 GLfloat t = span->attrStart[attr][1] + span->leftClip * dtdx; 494 GLfloat r = span->attrStart[attr][2] + span->leftClip * drdx; 495 GLfloat q = span->attrStart[attr][3] + span->leftClip * dqdx; 496 497 if (obj) { 498 const struct gl_texture_image *img = obj->Image[0][obj->BaseLevel]; 499 const struct swrast_texture_image *swImg = 500 swrast_texture_image_const(img); 501 const struct gl_sampler_object *samp = _mesa_get_samplerobj(ctx, u); 502 503 needLambda = (samp->MinFilter != samp->MagFilter) 504 || _swrast_use_fragment_program(ctx); 505 /* LOD is calculated directly in the ansiotropic filter, we can 506 * skip the normal lambda function as the result is ignored. 507 */ 508 if (samp->MaxAnisotropy > 1.0 && 509 samp->MinFilter == GL_LINEAR_MIPMAP_LINEAR) { 510 needLambda = GL_FALSE; 511 } 512 texW = swImg->WidthScale; 513 texH = swImg->HeightScale; 514 } 515 else { 516 /* using a fragment program */ 517 texW = 1.0; 518 texH = 1.0; 519 needLambda = GL_FALSE; 520 } 521 522 if (needLambda) { 523 GLuint i; 524 if (_swrast_use_fragment_program(ctx) 525 || ctx->ATIFragmentShader._Enabled) { 526 /* do perspective correction but don't divide s, t, r by q */ 527 const GLfloat dwdx = span->attrStepX[FRAG_ATTRIB_WPOS][3]; 528 GLfloat w = span->attrStart[FRAG_ATTRIB_WPOS][3] + span->leftClip * dwdx; 529 for (i = 0; i < span->end; i++) { 530 const GLfloat invW = 1.0F / w; 531 texcoord[i][0] = s * invW; 532 texcoord[i][1] = t * invW; 533 texcoord[i][2] = r * invW; 534 texcoord[i][3] = q * invW; 535 lambda[i] = _swrast_compute_lambda(dsdx, dsdy, dtdx, dtdy, 536 dqdx, dqdy, texW, texH, 537 s, t, q, invW); 538 s += dsdx; 539 t += dtdx; 540 r += drdx; 541 q += dqdx; 542 w += dwdx; 543 } 544 } 545 else { 546 for (i = 0; i < span->end; i++) { 547 const GLfloat invQ = (q == 0.0F) ? 1.0F : (1.0F / q); 548 texcoord[i][0] = s * invQ; 549 texcoord[i][1] = t * invQ; 550 texcoord[i][2] = r * invQ; 551 texcoord[i][3] = q; 552 lambda[i] = _swrast_compute_lambda(dsdx, dsdy, dtdx, dtdy, 553 dqdx, dqdy, texW, texH, 554 s, t, q, invQ); 555 s += dsdx; 556 t += dtdx; 557 r += drdx; 558 q += dqdx; 559 } 560 } 561 span->arrayMask |= SPAN_LAMBDA; 562 } 563 else { 564 GLuint i; 565 if (_swrast_use_fragment_program(ctx) || 566 ctx->ATIFragmentShader._Enabled) { 567 /* do perspective correction but don't divide s, t, r by q */ 568 const GLfloat dwdx = span->attrStepX[FRAG_ATTRIB_WPOS][3]; 569 GLfloat w = span->attrStart[FRAG_ATTRIB_WPOS][3] + span->leftClip * dwdx; 570 for (i = 0; i < span->end; i++) { 571 const GLfloat invW = 1.0F / w; 572 texcoord[i][0] = s * invW; 573 texcoord[i][1] = t * invW; 574 texcoord[i][2] = r * invW; 575 texcoord[i][3] = q * invW; 576 lambda[i] = 0.0; 577 s += dsdx; 578 t += dtdx; 579 r += drdx; 580 q += dqdx; 581 w += dwdx; 582 } 583 } 584 else if (dqdx == 0.0F) { 585 /* Ortho projection or polygon's parallel to window X axis */ 586 const GLfloat invQ = (q == 0.0F) ? 1.0F : (1.0F / q); 587 for (i = 0; i < span->end; i++) { 588 texcoord[i][0] = s * invQ; 589 texcoord[i][1] = t * invQ; 590 texcoord[i][2] = r * invQ; 591 texcoord[i][3] = q; 592 lambda[i] = 0.0; 593 s += dsdx; 594 t += dtdx; 595 r += drdx; 596 } 597 } 598 else { 599 for (i = 0; i < span->end; i++) { 600 const GLfloat invQ = (q == 0.0F) ? 1.0F : (1.0F / q); 601 texcoord[i][0] = s * invQ; 602 texcoord[i][1] = t * invQ; 603 texcoord[i][2] = r * invQ; 604 texcoord[i][3] = q; 605 lambda[i] = 0.0; 606 s += dsdx; 607 t += dtdx; 608 r += drdx; 609 q += dqdx; 610 } 611 } 612 } /* lambda */ 613 } /* if */ 614 } /* for */ 615 } 616 617 618 /** 619 * Fill in the arrays->attribs[FRAG_ATTRIB_WPOS] array. 620 */ 621 static inline void 622 interpolate_wpos(struct gl_context *ctx, SWspan *span) 623 { 624 GLfloat (*wpos)[4] = span->array->attribs[FRAG_ATTRIB_WPOS]; 625 GLuint i; 626 const GLfloat zScale = 1.0F / ctx->DrawBuffer->_DepthMaxF; 627 GLfloat w, dw; 628 629 if (span->arrayMask & SPAN_XY) { 630 for (i = 0; i < span->end; i++) { 631 wpos[i][0] = (GLfloat) span->array->x[i]; 632 wpos[i][1] = (GLfloat) span->array->y[i]; 633 } 634 } 635 else { 636 for (i = 0; i < span->end; i++) { 637 wpos[i][0] = (GLfloat) span->x + i; 638 wpos[i][1] = (GLfloat) span->y; 639 } 640 } 641 642 dw = span->attrStepX[FRAG_ATTRIB_WPOS][3]; 643 w = span->attrStart[FRAG_ATTRIB_WPOS][3] + span->leftClip * dw; 644 for (i = 0; i < span->end; i++) { 645 wpos[i][2] = (GLfloat) span->array->z[i] * zScale; 646 wpos[i][3] = w; 647 w += dw; 648 } 649 } 650 651 652 /** 653 * Apply the current polygon stipple pattern to a span of pixels. 654 */ 655 static inline void 656 stipple_polygon_span(struct gl_context *ctx, SWspan *span) 657 { 658 GLubyte *mask = span->array->mask; 659 660 ASSERT(ctx->Polygon.StippleFlag); 661 662 if (span->arrayMask & SPAN_XY) { 663 /* arrays of x/y pixel coords */ 664 GLuint i; 665 for (i = 0; i < span->end; i++) { 666 const GLint col = span->array->x[i] % 32; 667 const GLint row = span->array->y[i] % 32; 668 const GLuint stipple = ctx->PolygonStipple[row]; 669 if (((1 << col) & stipple) == 0) { 670 mask[i] = 0; 671 } 672 } 673 } 674 else { 675 /* horizontal span of pixels */ 676 const GLuint highBit = 1 << 31; 677 const GLuint stipple = ctx->PolygonStipple[span->y % 32]; 678 GLuint i, m = highBit >> (GLuint) (span->x % 32); 679 for (i = 0; i < span->end; i++) { 680 if ((m & stipple) == 0) { 681 mask[i] = 0; 682 } 683 m = m >> 1; 684 if (m == 0) { 685 m = highBit; 686 } 687 } 688 } 689 span->writeAll = GL_FALSE; 690 } 691 692 693 /** 694 * Clip a pixel span to the current buffer/window boundaries: 695 * DrawBuffer->_Xmin, _Xmax, _Ymin, _Ymax. This will accomplish 696 * window clipping and scissoring. 697 * Return: GL_TRUE some pixels still visible 698 * GL_FALSE nothing visible 699 */ 700 static inline GLuint 701 clip_span( struct gl_context *ctx, SWspan *span ) 702 { 703 const GLint xmin = ctx->DrawBuffer->_Xmin; 704 const GLint xmax = ctx->DrawBuffer->_Xmax; 705 const GLint ymin = ctx->DrawBuffer->_Ymin; 706 const GLint ymax = ctx->DrawBuffer->_Ymax; 707 708 span->leftClip = 0; 709 710 if (span->arrayMask & SPAN_XY) { 711 /* arrays of x/y pixel coords */ 712 const GLint *x = span->array->x; 713 const GLint *y = span->array->y; 714 const GLint n = span->end; 715 GLubyte *mask = span->array->mask; 716 GLint i; 717 GLuint passed = 0; 718 if (span->arrayMask & SPAN_MASK) { 719 /* note: using & intead of && to reduce branches */ 720 for (i = 0; i < n; i++) { 721 mask[i] &= (x[i] >= xmin) & (x[i] < xmax) 722 & (y[i] >= ymin) & (y[i] < ymax); 723 passed += mask[i]; 724 } 725 } 726 else { 727 /* note: using & intead of && to reduce branches */ 728 for (i = 0; i < n; i++) { 729 mask[i] = (x[i] >= xmin) & (x[i] < xmax) 730 & (y[i] >= ymin) & (y[i] < ymax); 731 passed += mask[i]; 732 } 733 } 734 return passed > 0; 735 } 736 else { 737 /* horizontal span of pixels */ 738 const GLint x = span->x; 739 const GLint y = span->y; 740 GLint n = span->end; 741 742 /* Trivial rejection tests */ 743 if (y < ymin || y >= ymax || x + n <= xmin || x >= xmax) { 744 span->end = 0; 745 return GL_FALSE; /* all pixels clipped */ 746 } 747 748 /* Clip to right */ 749 if (x + n > xmax) { 750 ASSERT(x < xmax); 751 n = span->end = xmax - x; 752 } 753 754 /* Clip to the left */ 755 if (x < xmin) { 756 const GLint leftClip = xmin - x; 757 GLuint i; 758 759 ASSERT(leftClip > 0); 760 ASSERT(x + n > xmin); 761 762 /* Clip 'leftClip' pixels from the left side. 763 * The span->leftClip field will be applied when we interpolate 764 * fragment attributes. 765 * For arrays of values, shift them left. 766 */ 767 for (i = 0; i < FRAG_ATTRIB_MAX; i++) { 768 if (span->interpMask & (1 << i)) { 769 GLuint j; 770 for (j = 0; j < 4; j++) { 771 span->attrStart[i][j] += leftClip * span->attrStepX[i][j]; 772 } 773 } 774 } 775 776 span->red += leftClip * span->redStep; 777 span->green += leftClip * span->greenStep; 778 span->blue += leftClip * span->blueStep; 779 span->alpha += leftClip * span->alphaStep; 780 span->index += leftClip * span->indexStep; 781 span->z += leftClip * span->zStep; 782 span->intTex[0] += leftClip * span->intTexStep[0]; 783 span->intTex[1] += leftClip * span->intTexStep[1]; 784 785 #define SHIFT_ARRAY(ARRAY, SHIFT, LEN) \ 786 memmove(ARRAY, ARRAY + (SHIFT), (LEN) * sizeof(ARRAY[0])) 787 788 for (i = 0; i < FRAG_ATTRIB_MAX; i++) { 789 if (span->arrayAttribs & (1 << i)) { 790 /* shift array elements left by 'leftClip' */ 791 SHIFT_ARRAY(span->array->attribs[i], leftClip, n - leftClip); 792 } 793 } 794 795 SHIFT_ARRAY(span->array->mask, leftClip, n - leftClip); 796 SHIFT_ARRAY(span->array->rgba8, leftClip, n - leftClip); 797 SHIFT_ARRAY(span->array->rgba16, leftClip, n - leftClip); 798 SHIFT_ARRAY(span->array->x, leftClip, n - leftClip); 799 SHIFT_ARRAY(span->array->y, leftClip, n - leftClip); 800 SHIFT_ARRAY(span->array->z, leftClip, n - leftClip); 801 SHIFT_ARRAY(span->array->index, leftClip, n - leftClip); 802 for (i = 0; i < MAX_TEXTURE_COORD_UNITS; i++) { 803 SHIFT_ARRAY(span->array->lambda[i], leftClip, n - leftClip); 804 } 805 SHIFT_ARRAY(span->array->coverage, leftClip, n - leftClip); 806 807 #undef SHIFT_ARRAY 808 809 span->leftClip = leftClip; 810 span->x = xmin; 811 span->end -= leftClip; 812 span->writeAll = GL_FALSE; 813 } 814 815 ASSERT(span->x >= xmin); 816 ASSERT(span->x + span->end <= xmax); 817 ASSERT(span->y >= ymin); 818 ASSERT(span->y < ymax); 819 820 return GL_TRUE; /* some pixels visible */ 821 } 822 } 823 824 825 /** 826 * Add specular colors to primary colors. 827 * Only called during fixed-function operation. 828 * Result is float color array (FRAG_ATTRIB_COL0). 829 */ 830 static inline void 831 add_specular(struct gl_context *ctx, SWspan *span) 832 { 833 const SWcontext *swrast = SWRAST_CONTEXT(ctx); 834 const GLubyte *mask = span->array->mask; 835 GLfloat (*col0)[4] = span->array->attribs[FRAG_ATTRIB_COL0]; 836 GLfloat (*col1)[4] = span->array->attribs[FRAG_ATTRIB_COL1]; 837 GLuint i; 838 839 ASSERT(!_swrast_use_fragment_program(ctx)); 840 ASSERT(span->arrayMask & SPAN_RGBA); 841 ASSERT(swrast->_ActiveAttribMask & FRAG_BIT_COL1); 842 (void) swrast; /* silence warning */ 843 844 if (span->array->ChanType == GL_FLOAT) { 845 if ((span->arrayAttribs & FRAG_BIT_COL0) == 0) { 846 interpolate_active_attribs(ctx, span, FRAG_BIT_COL0); 847 } 848 } 849 else { 850 /* need float colors */ 851 if ((span->arrayAttribs & FRAG_BIT_COL0) == 0) { 852 interpolate_float_colors(span); 853 } 854 } 855 856 if ((span->arrayAttribs & FRAG_BIT_COL1) == 0) { 857 /* XXX could avoid this and interpolate COL1 in the loop below */ 858 interpolate_active_attribs(ctx, span, FRAG_BIT_COL1); 859 } 860 861 ASSERT(span->arrayAttribs & FRAG_BIT_COL0); 862 ASSERT(span->arrayAttribs & FRAG_BIT_COL1); 863 864 for (i = 0; i < span->end; i++) { 865 if (mask[i]) { 866 col0[i][0] += col1[i][0]; 867 col0[i][1] += col1[i][1]; 868 col0[i][2] += col1[i][2]; 869 } 870 } 871 872 span->array->ChanType = GL_FLOAT; 873 } 874 875 876 /** 877 * Apply antialiasing coverage value to alpha values. 878 */ 879 static inline void 880 apply_aa_coverage(SWspan *span) 881 { 882 const GLfloat *coverage = span->array->coverage; 883 GLuint i; 884 if (span->array->ChanType == GL_UNSIGNED_BYTE) { 885 GLubyte (*rgba)[4] = span->array->rgba8; 886 for (i = 0; i < span->end; i++) { 887 const GLfloat a = rgba[i][ACOMP] * coverage[i]; 888 rgba[i][ACOMP] = (GLubyte) CLAMP(a, 0.0, 255.0); 889 ASSERT(coverage[i] >= 0.0); 890 ASSERT(coverage[i] <= 1.0); 891 } 892 } 893 else if (span->array->ChanType == GL_UNSIGNED_SHORT) { 894 GLushort (*rgba)[4] = span->array->rgba16; 895 for (i = 0; i < span->end; i++) { 896 const GLfloat a = rgba[i][ACOMP] * coverage[i]; 897 rgba[i][ACOMP] = (GLushort) CLAMP(a, 0.0, 65535.0); 898 } 899 } 900 else { 901 GLfloat (*rgba)[4] = span->array->attribs[FRAG_ATTRIB_COL0]; 902 for (i = 0; i < span->end; i++) { 903 rgba[i][ACOMP] = rgba[i][ACOMP] * coverage[i]; 904 /* clamp later */ 905 } 906 } 907 } 908 909 910 /** 911 * Clamp span's float colors to [0,1] 912 */ 913 static inline void 914 clamp_colors(SWspan *span) 915 { 916 GLfloat (*rgba)[4] = span->array->attribs[FRAG_ATTRIB_COL0]; 917 GLuint i; 918 ASSERT(span->array->ChanType == GL_FLOAT); 919 for (i = 0; i < span->end; i++) { 920 rgba[i][RCOMP] = CLAMP(rgba[i][RCOMP], 0.0F, 1.0F); 921 rgba[i][GCOMP] = CLAMP(rgba[i][GCOMP], 0.0F, 1.0F); 922 rgba[i][BCOMP] = CLAMP(rgba[i][BCOMP], 0.0F, 1.0F); 923 rgba[i][ACOMP] = CLAMP(rgba[i][ACOMP], 0.0F, 1.0F); 924 } 925 } 926 927 928 /** 929 * Convert the span's color arrays to the given type. 930 * The only way 'output' can be greater than zero is when we have a fragment 931 * program that writes to gl_FragData[1] or higher. 932 * \param output which fragment program color output is being processed 933 */ 934 static inline void 935 convert_color_type(SWspan *span, GLenum newType, GLuint output) 936 { 937 GLvoid *src, *dst; 938 939 if (output > 0 || span->array->ChanType == GL_FLOAT) { 940 src = span->array->attribs[FRAG_ATTRIB_COL0 + output]; 941 span->array->ChanType = GL_FLOAT; 942 } 943 else if (span->array->ChanType == GL_UNSIGNED_BYTE) { 944 src = span->array->rgba8; 945 } 946 else { 947 ASSERT(span->array->ChanType == GL_UNSIGNED_SHORT); 948 src = span->array->rgba16; 949 } 950 951 if (newType == GL_UNSIGNED_BYTE) { 952 dst = span->array->rgba8; 953 } 954 else if (newType == GL_UNSIGNED_SHORT) { 955 dst = span->array->rgba16; 956 } 957 else { 958 dst = span->array->attribs[FRAG_ATTRIB_COL0]; 959 } 960 961 _mesa_convert_colors(span->array->ChanType, src, 962 newType, dst, 963 span->end, span->array->mask); 964 965 span->array->ChanType = newType; 966 span->array->rgba = dst; 967 } 968 969 970 971 /** 972 * Apply fragment shader, fragment program or normal texturing to span. 973 */ 974 static inline void 975 shade_texture_span(struct gl_context *ctx, SWspan *span) 976 { 977 if (_swrast_use_fragment_program(ctx) || 978 ctx->ATIFragmentShader._Enabled) { 979 /* programmable shading */ 980 if (span->primitive == GL_BITMAP && span->array->ChanType != GL_FLOAT) { 981 convert_color_type(span, GL_FLOAT, 0); 982 } 983 else { 984 span->array->rgba = (void *) span->array->attribs[FRAG_ATTRIB_COL0]; 985 } 986 987 if (span->primitive != GL_POINT || 988 (span->interpMask & SPAN_RGBA) || 989 ctx->Point.PointSprite) { 990 /* for single-pixel points, we populated the arrays already */ 991 interpolate_active_attribs(ctx, span, ~0); 992 } 993 span->array->ChanType = GL_FLOAT; 994 995 if (!(span->arrayMask & SPAN_Z)) 996 _swrast_span_interpolate_z (ctx, span); 997 998 #if 0 999 if (inputsRead & FRAG_BIT_WPOS) 1000 #else 1001 /* XXX always interpolate wpos so that DDX/DDY work */ 1002 #endif 1003 interpolate_wpos(ctx, span); 1004 1005 /* Run fragment program/shader now */ 1006 if (_swrast_use_fragment_program(ctx)) { 1007 _swrast_exec_fragment_program(ctx, span); 1008 } 1009 else { 1010 ASSERT(ctx->ATIFragmentShader._Enabled); 1011 _swrast_exec_fragment_shader(ctx, span); 1012 } 1013 } 1014 else if (ctx->Texture._EnabledCoordUnits) { 1015 /* conventional texturing */ 1016 1017 #if CHAN_BITS == 32 1018 if ((span->arrayAttribs & FRAG_BIT_COL0) == 0) { 1019 interpolate_int_colors(ctx, span); 1020 } 1021 #else 1022 if (!(span->arrayMask & SPAN_RGBA)) 1023 interpolate_int_colors(ctx, span); 1024 #endif 1025 if ((span->arrayAttribs & FRAG_BITS_TEX_ANY) == 0x0) 1026 interpolate_texcoords(ctx, span); 1027 1028 _swrast_texture_span(ctx, span); 1029 } 1030 } 1031 1032 1033 /** Put colors at x/y locations into a renderbuffer */ 1034 static void 1035 put_values(struct gl_context *ctx, struct gl_renderbuffer *rb, 1036 GLenum datatype, 1037 GLuint count, const GLint x[], const GLint y[], 1038 const void *values, const GLubyte *mask) 1039 { 1040 gl_pack_ubyte_rgba_func pack_ubyte = NULL; 1041 gl_pack_float_rgba_func pack_float = NULL; 1042 GLuint i; 1043 1044 if (datatype == GL_UNSIGNED_BYTE) 1045 pack_ubyte = _mesa_get_pack_ubyte_rgba_function(rb->Format); 1046 else 1047 pack_float = _mesa_get_pack_float_rgba_function(rb->Format); 1048 1049 for (i = 0; i < count; i++) { 1050 if (mask[i]) { 1051 GLubyte *dst = _swrast_pixel_address(rb, x[i], y[i]); 1052 1053 if (datatype == GL_UNSIGNED_BYTE) { 1054 pack_ubyte((const GLubyte *) values + 4 * i, dst); 1055 } 1056 else { 1057 assert(datatype == GL_FLOAT); 1058 pack_float((const GLfloat *) values + 4 * i, dst); 1059 } 1060 } 1061 } 1062 } 1063 1064 1065 /** Put row of colors into renderbuffer */ 1066 void 1067 _swrast_put_row(struct gl_context *ctx, struct gl_renderbuffer *rb, 1068 GLenum datatype, 1069 GLuint count, GLint x, GLint y, 1070 const void *values, const GLubyte *mask) 1071 { 1072 GLubyte *dst = _swrast_pixel_address(rb, x, y); 1073 1074 if (!mask) { 1075 if (datatype == GL_UNSIGNED_BYTE) { 1076 _mesa_pack_ubyte_rgba_row(rb->Format, count, 1077 (const GLubyte (*)[4]) values, dst); 1078 } 1079 else { 1080 assert(datatype == GL_FLOAT); 1081 _mesa_pack_float_rgba_row(rb->Format, count, 1082 (const GLfloat (*)[4]) values, dst); 1083 } 1084 } 1085 else { 1086 const GLuint bpp = _mesa_get_format_bytes(rb->Format); 1087 GLuint i, runLen, runStart; 1088 /* We can't pass a 'mask' array to the _mesa_pack_rgba_row() functions 1089 * so look for runs where mask=1... 1090 */ 1091 runLen = runStart = 0; 1092 for (i = 0; i < count; i++) { 1093 if (mask[i]) { 1094 if (runLen == 0) 1095 runStart = i; 1096 runLen++; 1097 } 1098 1099 if (!mask[i] || i == count - 1) { 1100 /* might be the end of a run of pixels */ 1101 if (runLen > 0) { 1102 if (datatype == GL_UNSIGNED_BYTE) { 1103 _mesa_pack_ubyte_rgba_row(rb->Format, runLen, 1104 (const GLubyte (*)[4]) values + runStart, 1105 dst + runStart * bpp); 1106 } 1107 else { 1108 assert(datatype == GL_FLOAT); 1109 _mesa_pack_float_rgba_row(rb->Format, runLen, 1110 (const GLfloat (*)[4]) values + runStart, 1111 dst + runStart * bpp); 1112 } 1113 runLen = 0; 1114 } 1115 } 1116 } 1117 } 1118 } 1119 1120 1121 1122 /** 1123 * Apply all the per-fragment operations to a span. 1124 * This now includes texturing (_swrast_write_texture_span() is history). 1125 * This function may modify any of the array values in the span. 1126 * span->interpMask and span->arrayMask may be changed but will be restored 1127 * to their original values before returning. 1128 */ 1129 void 1130 _swrast_write_rgba_span( struct gl_context *ctx, SWspan *span) 1131 { 1132 const SWcontext *swrast = SWRAST_CONTEXT(ctx); 1133 const GLuint *colorMask = (GLuint *) ctx->Color.ColorMask; 1134 const GLbitfield origInterpMask = span->interpMask; 1135 const GLbitfield origArrayMask = span->arrayMask; 1136 const GLbitfield64 origArrayAttribs = span->arrayAttribs; 1137 const GLenum origChanType = span->array->ChanType; 1138 void * const origRgba = span->array->rgba; 1139 const GLboolean shader = (_swrast_use_fragment_program(ctx) 1140 || ctx->ATIFragmentShader._Enabled); 1141 const GLboolean shaderOrTexture = shader || ctx->Texture._EnabledCoordUnits; 1142 struct gl_framebuffer *fb = ctx->DrawBuffer; 1143 1144 /* 1145 printf("%s() interp 0x%x array 0x%x\n", __FUNCTION__, 1146 span->interpMask, span->arrayMask); 1147 */ 1148 1149 ASSERT(span->primitive == GL_POINT || 1150 span->primitive == GL_LINE || 1151 span->primitive == GL_POLYGON || 1152 span->primitive == GL_BITMAP); 1153 1154 /* Fragment write masks */ 1155 if (span->arrayMask & SPAN_MASK) { 1156 /* mask was initialized by caller, probably glBitmap */ 1157 span->writeAll = GL_FALSE; 1158 } 1159 else { 1160 memset(span->array->mask, 1, span->end); 1161 span->writeAll = GL_TRUE; 1162 } 1163 1164 /* Clip to window/scissor box */ 1165 if (!clip_span(ctx, span)) { 1166 return; 1167 } 1168 1169 ASSERT(span->end <= SWRAST_MAX_WIDTH); 1170 1171 /* Depth bounds test */ 1172 if (ctx->Depth.BoundsTest && fb->Visual.depthBits > 0) { 1173 if (!_swrast_depth_bounds_test(ctx, span)) { 1174 return; 1175 } 1176 } 1177 1178 #ifdef DEBUG 1179 /* Make sure all fragments are within window bounds */ 1180 if (span->arrayMask & SPAN_XY) { 1181 /* array of pixel locations */ 1182 GLuint i; 1183 for (i = 0; i < span->end; i++) { 1184 if (span->array->mask[i]) { 1185 assert(span->array->x[i] >= fb->_Xmin); 1186 assert(span->array->x[i] < fb->_Xmax); 1187 assert(span->array->y[i] >= fb->_Ymin); 1188 assert(span->array->y[i] < fb->_Ymax); 1189 } 1190 } 1191 } 1192 #endif 1193 1194 /* Polygon Stippling */ 1195 if (ctx->Polygon.StippleFlag && span->primitive == GL_POLYGON) { 1196 stipple_polygon_span(ctx, span); 1197 } 1198 1199 /* This is the normal place to compute the fragment color/Z 1200 * from texturing or shading. 1201 */ 1202 if (shaderOrTexture && !swrast->_DeferredTexture) { 1203 shade_texture_span(ctx, span); 1204 } 1205 1206 /* Do the alpha test */ 1207 if (ctx->Color.AlphaEnabled) { 1208 if (!_swrast_alpha_test(ctx, span)) { 1209 /* all fragments failed test */ 1210 goto end; 1211 } 1212 } 1213 1214 /* Stencil and Z testing */ 1215 if (ctx->Stencil._Enabled || ctx->Depth.Test) { 1216 if (!(span->arrayMask & SPAN_Z)) 1217 _swrast_span_interpolate_z(ctx, span); 1218 1219 if (ctx->Transform.DepthClamp) 1220 _swrast_depth_clamp_span(ctx, span); 1221 1222 if (ctx->Stencil._Enabled) { 1223 /* Combined Z/stencil tests */ 1224 if (!_swrast_stencil_and_ztest_span(ctx, span)) { 1225 /* all fragments failed test */ 1226 goto end; 1227 } 1228 } 1229 else if (fb->Visual.depthBits > 0) { 1230 /* Just regular depth testing */ 1231 ASSERT(ctx->Depth.Test); 1232 ASSERT(span->arrayMask & SPAN_Z); 1233 if (!_swrast_depth_test_span(ctx, span)) { 1234 /* all fragments failed test */ 1235 goto end; 1236 } 1237 } 1238 } 1239 1240 if (ctx->Query.CurrentOcclusionObject) { 1241 /* update count of 'passed' fragments */ 1242 struct gl_query_object *q = ctx->Query.CurrentOcclusionObject; 1243 GLuint i; 1244 for (i = 0; i < span->end; i++) 1245 q->Result += span->array->mask[i]; 1246 } 1247 1248 /* We had to wait until now to check for glColorMask(0,0,0,0) because of 1249 * the occlusion test. 1250 */ 1251 if (fb->_NumColorDrawBuffers == 1 && colorMask[0] == 0x0) { 1252 /* no colors to write */ 1253 goto end; 1254 } 1255 1256 /* If we were able to defer fragment color computation to now, there's 1257 * a good chance that many fragments will have already been killed by 1258 * Z/stencil testing. 1259 */ 1260 if (shaderOrTexture && swrast->_DeferredTexture) { 1261 shade_texture_span(ctx, span); 1262 } 1263 1264 #if CHAN_BITS == 32 1265 if ((span->arrayAttribs & FRAG_BIT_COL0) == 0) { 1266 interpolate_active_attribs(ctx, span, FRAG_BIT_COL0); 1267 } 1268 #else 1269 if ((span->arrayMask & SPAN_RGBA) == 0) { 1270 interpolate_int_colors(ctx, span); 1271 } 1272 #endif 1273 1274 ASSERT(span->arrayMask & SPAN_RGBA); 1275 1276 if (span->primitive == GL_BITMAP || !swrast->SpecularVertexAdd) { 1277 /* Add primary and specular (diffuse + specular) colors */ 1278 if (!shader) { 1279 if (ctx->Fog.ColorSumEnabled || 1280 (ctx->Light.Enabled && 1281 ctx->Light.Model.ColorControl == GL_SEPARATE_SPECULAR_COLOR)) { 1282 add_specular(ctx, span); 1283 } 1284 } 1285 } 1286 1287 /* Fog */ 1288 if (swrast->_FogEnabled) { 1289 _swrast_fog_rgba_span(ctx, span); 1290 } 1291 1292 /* Antialias coverage application */ 1293 if (span->arrayMask & SPAN_COVERAGE) { 1294 apply_aa_coverage(span); 1295 } 1296 1297 /* Clamp color/alpha values over the range [0.0, 1.0] before storage */ 1298 if (ctx->Color.ClampFragmentColor == GL_TRUE && 1299 span->array->ChanType == GL_FLOAT) { 1300 clamp_colors(span); 1301 } 1302 1303 /* 1304 * Write to renderbuffers. 1305 * Depending on glDrawBuffer() state and the which color outputs are 1306 * written by the fragment shader, we may either replicate one color to 1307 * all renderbuffers or write a different color to each renderbuffer. 1308 * multiFragOutputs=TRUE for the later case. 1309 */ 1310 { 1311 const GLuint numBuffers = fb->_NumColorDrawBuffers; 1312 const struct gl_fragment_program *fp = ctx->FragmentProgram._Current; 1313 const GLboolean multiFragOutputs = 1314 _swrast_use_fragment_program(ctx) 1315 && fp->Base.OutputsWritten >= (1 << FRAG_RESULT_DATA0); 1316 GLuint buf; 1317 1318 for (buf = 0; buf < numBuffers; buf++) { 1319 struct gl_renderbuffer *rb = fb->_ColorDrawBuffers[buf]; 1320 1321 /* color[fragOutput] will be written to buffer[buf] */ 1322 1323 if (rb) { 1324 /* re-use one of the attribute array buffers for rgbaSave */ 1325 GLchan (*rgbaSave)[4] = (GLchan (*)[4]) span->array->attribs[0]; 1326 struct swrast_renderbuffer *srb = swrast_renderbuffer(rb); 1327 GLenum colorType = srb->ColorType; 1328 1329 assert(colorType == GL_UNSIGNED_BYTE || 1330 colorType == GL_FLOAT); 1331 1332 /* set span->array->rgba to colors for renderbuffer's datatype */ 1333 if (span->array->ChanType != colorType) { 1334 convert_color_type(span, colorType, 0); 1335 } 1336 else { 1337 if (span->array->ChanType == GL_UNSIGNED_BYTE) { 1338 span->array->rgba = span->array->rgba8; 1339 } 1340 else { 1341 span->array->rgba = (void *) 1342 span->array->attribs[FRAG_ATTRIB_COL0]; 1343 } 1344 } 1345 1346 if (!multiFragOutputs && numBuffers > 1) { 1347 /* save colors for second, third renderbuffer writes */ 1348 memcpy(rgbaSave, span->array->rgba, 1349 4 * span->end * sizeof(GLchan)); 1350 } 1351 1352 ASSERT(rb->_BaseFormat == GL_RGBA || 1353 rb->_BaseFormat == GL_RGB || 1354 rb->_BaseFormat == GL_RED || 1355 rb->_BaseFormat == GL_RG || 1356 rb->_BaseFormat == GL_ALPHA); 1357 1358 if (ctx->Color.ColorLogicOpEnabled) { 1359 _swrast_logicop_rgba_span(ctx, rb, span); 1360 } 1361 else if ((ctx->Color.BlendEnabled >> buf) & 1) { 1362 _swrast_blend_span(ctx, rb, span); 1363 } 1364 1365 if (colorMask[buf] != 0xffffffff) { 1366 _swrast_mask_rgba_span(ctx, rb, span, buf); 1367 } 1368 1369 if (span->arrayMask & SPAN_XY) { 1370 /* array of pixel coords */ 1371 put_values(ctx, rb, 1372 span->array->ChanType, span->end, 1373 span->array->x, span->array->y, 1374 span->array->rgba, span->array->mask); 1375 } 1376 else { 1377 /* horizontal run of pixels */ 1378 _swrast_put_row(ctx, rb, 1379 span->array->ChanType, 1380 span->end, span->x, span->y, 1381 span->array->rgba, 1382 span->writeAll ? NULL: span->array->mask); 1383 } 1384 1385 if (!multiFragOutputs && numBuffers > 1) { 1386 /* restore original span values */ 1387 memcpy(span->array->rgba, rgbaSave, 1388 4 * span->end * sizeof(GLchan)); 1389 } 1390 1391 } /* if rb */ 1392 } /* for buf */ 1393 } 1394 1395 end: 1396 /* restore these values before returning */ 1397 span->interpMask = origInterpMask; 1398 span->arrayMask = origArrayMask; 1399 span->arrayAttribs = origArrayAttribs; 1400 span->array->ChanType = origChanType; 1401 span->array->rgba = origRgba; 1402 } 1403 1404 1405 /** 1406 * Read float RGBA pixels from a renderbuffer. Clipping will be done to 1407 * prevent reading ouside the buffer's boundaries. 1408 * \param rgba the returned colors 1409 */ 1410 void 1411 _swrast_read_rgba_span( struct gl_context *ctx, struct gl_renderbuffer *rb, 1412 GLuint n, GLint x, GLint y, 1413 GLvoid *rgba) 1414 { 1415 struct swrast_renderbuffer *srb = swrast_renderbuffer(rb); 1416 GLenum dstType = GL_FLOAT; 1417 const GLint bufWidth = (GLint) rb->Width; 1418 const GLint bufHeight = (GLint) rb->Height; 1419 1420 if (y < 0 || y >= bufHeight || x + (GLint) n < 0 || x >= bufWidth) { 1421 /* completely above, below, or right */ 1422 /* XXX maybe leave rgba values undefined? */ 1423 memset(rgba, 0, 4 * n * sizeof(GLchan)); 1424 } 1425 else { 1426 GLint skip, length; 1427 GLubyte *src; 1428 1429 if (x < 0) { 1430 /* left edge clipping */ 1431 skip = -x; 1432 length = (GLint) n - skip; 1433 if (length < 0) { 1434 /* completely left of window */ 1435 return; 1436 } 1437 if (length > bufWidth) { 1438 length = bufWidth; 1439 } 1440 } 1441 else if ((GLint) (x + n) > bufWidth) { 1442 /* right edge clipping */ 1443 skip = 0; 1444 length = bufWidth - x; 1445 if (length < 0) { 1446 /* completely to right of window */ 1447 return; 1448 } 1449 } 1450 else { 1451 /* no clipping */ 1452 skip = 0; 1453 length = (GLint) n; 1454 } 1455 1456 ASSERT(rb); 1457 ASSERT(rb->_BaseFormat == GL_RGBA || 1458 rb->_BaseFormat == GL_RGB || 1459 rb->_BaseFormat == GL_RG || 1460 rb->_BaseFormat == GL_RED || 1461 rb->_BaseFormat == GL_LUMINANCE || 1462 rb->_BaseFormat == GL_INTENSITY || 1463 rb->_BaseFormat == GL_LUMINANCE_ALPHA || 1464 rb->_BaseFormat == GL_ALPHA); 1465 1466 assert(srb->Map); 1467 1468 src = _swrast_pixel_address(rb, x + skip, y); 1469 1470 if (dstType == GL_UNSIGNED_BYTE) { 1471 _mesa_unpack_ubyte_rgba_row(rb->Format, length, src, 1472 (GLubyte (*)[4]) rgba + skip); 1473 } 1474 else if (dstType == GL_FLOAT) { 1475 _mesa_unpack_rgba_row(rb->Format, length, src, 1476 (GLfloat (*)[4]) rgba + skip); 1477 } 1478 else { 1479 _mesa_problem(ctx, "unexpected type in _swrast_read_rgba_span()"); 1480 } 1481 } 1482 } 1483 1484 1485 /** 1486 * Get colors at x/y positions with clipping. 1487 * \param type type of values to return 1488 */ 1489 static void 1490 get_values(struct gl_context *ctx, struct gl_renderbuffer *rb, 1491 GLuint count, const GLint x[], const GLint y[], 1492 void *values, GLenum type) 1493 { 1494 GLuint i; 1495 1496 for (i = 0; i < count; i++) { 1497 if (x[i] >= 0 && y[i] >= 0 && 1498 x[i] < (GLint) rb->Width && y[i] < (GLint) rb->Height) { 1499 /* inside */ 1500 const GLubyte *src = _swrast_pixel_address(rb, x[i], y[i]); 1501 1502 if (type == GL_UNSIGNED_BYTE) { 1503 _mesa_unpack_ubyte_rgba_row(rb->Format, 1, src, 1504 (GLubyte (*)[4]) values + i); 1505 } 1506 else if (type == GL_FLOAT) { 1507 _mesa_unpack_rgba_row(rb->Format, 1, src, 1508 (GLfloat (*)[4]) values + i); 1509 } 1510 else { 1511 _mesa_problem(ctx, "unexpected type in get_values()"); 1512 } 1513 } 1514 } 1515 } 1516 1517 1518 /** 1519 * Get row of colors with clipping. 1520 * \param type type of values to return 1521 */ 1522 static void 1523 get_row(struct gl_context *ctx, struct gl_renderbuffer *rb, 1524 GLuint count, GLint x, GLint y, 1525 GLvoid *values, GLenum type) 1526 { 1527 GLint skip = 0; 1528 GLubyte *src; 1529 1530 if (y < 0 || y >= (GLint) rb->Height) 1531 return; /* above or below */ 1532 1533 if (x + (GLint) count <= 0 || x >= (GLint) rb->Width) 1534 return; /* entirely left or right */ 1535 1536 if (x + count > rb->Width) { 1537 /* right clip */ 1538 GLint clip = x + count - rb->Width; 1539 count -= clip; 1540 } 1541 1542 if (x < 0) { 1543 /* left clip */ 1544 skip = -x; 1545 x = 0; 1546 count -= skip; 1547 } 1548 1549 src = _swrast_pixel_address(rb, x, y); 1550 1551 if (type == GL_UNSIGNED_BYTE) { 1552 _mesa_unpack_ubyte_rgba_row(rb->Format, count, src, 1553 (GLubyte (*)[4]) values + skip); 1554 } 1555 else if (type == GL_FLOAT) { 1556 _mesa_unpack_rgba_row(rb->Format, count, src, 1557 (GLfloat (*)[4]) values + skip); 1558 } 1559 else { 1560 _mesa_problem(ctx, "unexpected type in get_row()"); 1561 } 1562 } 1563 1564 1565 /** 1566 * Get RGBA pixels from the given renderbuffer. 1567 * Used by blending, logicop and masking functions. 1568 * \return pointer to the colors we read. 1569 */ 1570 void * 1571 _swrast_get_dest_rgba(struct gl_context *ctx, struct gl_renderbuffer *rb, 1572 SWspan *span) 1573 { 1574 void *rbPixels; 1575 1576 /* Point rbPixels to a temporary space */ 1577 rbPixels = span->array->attribs[FRAG_ATTRIB_MAX - 1]; 1578 1579 /* Get destination values from renderbuffer */ 1580 if (span->arrayMask & SPAN_XY) { 1581 get_values(ctx, rb, span->end, span->array->x, span->array->y, 1582 rbPixels, span->array->ChanType); 1583 } 1584 else { 1585 get_row(ctx, rb, span->end, span->x, span->y, 1586 rbPixels, span->array->ChanType); 1587 } 1588 1589 return rbPixels; 1590 } 1591
