diff options
Diffstat (limited to 'src/mesa/pipe/softpipe/sp_quad_depth_test.c')
| -rw-r--r-- | src/mesa/pipe/softpipe/sp_quad_depth_test.c | 169 |
1 files changed, 169 insertions, 0 deletions
diff --git a/src/mesa/pipe/softpipe/sp_quad_depth_test.c b/src/mesa/pipe/softpipe/sp_quad_depth_test.c new file mode 100644 index 0000000000..a26bd51d84 --- /dev/null +++ b/src/mesa/pipe/softpipe/sp_quad_depth_test.c @@ -0,0 +1,169 @@ +/* + * Mesa 3-D graphics library + * Version: 6.5 + * + * Copyright (C) 1999-2005 Brian Paul All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included + * in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN + * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + */ + +/** + * \brief Quad depth testing + */ + +#include "main/glheader.h" +#include "main/imports.h" +#include "pipe/p_defines.h" +#include "sp_context.h" +#include "sp_headers.h" +#include "sp_surface.h" +#include "sp_quad.h" + + +/** + * Do depth testing for a quad. + * Not static since it's used by the stencil code. + */ +void +sp_depth_test_quad(struct quad_stage *qs, struct quad_header *quad) +{ + struct softpipe_context *softpipe = qs->softpipe; + struct softpipe_surface *sps = softpipe_surface(softpipe->framebuffer.zbuf); + GLuint bzzzz[QUAD_SIZE]; /**< Z values fetched from depth buffer */ + GLuint qzzzz[QUAD_SIZE]; /**< Z values from the quad */ + GLuint zmask = 0; + GLuint j; + GLfloat scale; + + assert(sps); /* shouldn't get here if there's no zbuffer */ + + /* + * To increase efficiency, we should probably have multiple versions + * of this function that are specifically for Z16, Z32 and FP Z buffers. + * Try to effectively do that with codegen... + */ + if (sps->surface.format == PIPE_FORMAT_U_Z16) + scale = 65535.0; + else if (sps->surface.format == PIPE_FORMAT_Z24_S8) + scale = (float) ((1 << 24) - 1); + else + assert(0); /* XXX fix this someday */ + + /* + * Convert quad's float depth values to int depth values. + * If the Z buffer stores integer values, we _have_ to do the depth + * compares with integers (not floats). Otherwise, the float->int->float + * conversion of Z values (which isn't an identity function) will cause + * Z-fighting errors. + */ + for (j = 0; j < QUAD_SIZE; j++) { + qzzzz[j] = (GLuint) (quad->outputs.depth[j] * scale); + } + + /* get zquad from zbuffer */ + sps->read_quad_z(sps, quad->x0, quad->y0, bzzzz); + + switch (softpipe->depth_test.func) { + case PIPE_FUNC_NEVER: + /* zmask = 0 */ + break; + case PIPE_FUNC_LESS: + /* Note this is pretty much a single sse or cell instruction. + * Like this: quad->mask &= (quad->outputs.depth < zzzz); + */ + for (j = 0; j < QUAD_SIZE; j++) { + if (qzzzz[j] < bzzzz[j]) + zmask |= 1 << j; + } + break; + case PIPE_FUNC_EQUAL: + for (j = 0; j < QUAD_SIZE; j++) { + if (qzzzz[j] == bzzzz[j]) + zmask |= 1 << j; + } + break; + case PIPE_FUNC_LEQUAL: + for (j = 0; j < QUAD_SIZE; j++) { + if (qzzzz[j] <= bzzzz[j]) + zmask |= (1 << j); + } + break; + case PIPE_FUNC_GREATER: + for (j = 0; j < QUAD_SIZE; j++) { + if (qzzzz[j] > bzzzz[j]) + zmask |= (1 << j); + } + break; + case PIPE_FUNC_NOTEQUAL: + for (j = 0; j < QUAD_SIZE; j++) { + if (qzzzz[j] != bzzzz[j]) + zmask |= (1 << j); + } + break; + case PIPE_FUNC_GEQUAL: + for (j = 0; j < QUAD_SIZE; j++) { + if (qzzzz[j] >= bzzzz[j]) + zmask |= (1 << j); + } + break; + case PIPE_FUNC_ALWAYS: + zmask = MASK_ALL; + break; + default: + abort(); + } + + quad->mask &= zmask; + + if (softpipe->depth_test.writemask) { + + /* This is also efficient with sse / spe instructions: + */ + for (j = 0; j < QUAD_SIZE; j++) { + if (quad->mask & (1 << j)) { + bzzzz[j] = qzzzz[j]; + } + } + + /* write updated zquad to zbuffer */ + sps->write_quad_z(sps, quad->x0, quad->y0, bzzzz); + } +} + + +static void +depth_test_quad(struct quad_stage *qs, struct quad_header *quad) +{ + sp_depth_test_quad(qs, quad); + + if (quad->mask) + qs->next->run(qs->next, quad); +} + + + + +struct quad_stage *sp_quad_depth_test_stage( struct softpipe_context *softpipe ) +{ + struct quad_stage *stage = CALLOC_STRUCT(quad_stage); + + stage->softpipe = softpipe; + stage->run = depth_test_quad; + + return stage; +} |