Module: Mesa Branch: master Commit: 0cbe1e6c14c44da11a41470cd1328cdb67c76732 URL: http://cgit.freedesktop.org/mesa/mesa/commit/?id=0cbe1e6c14c44da11a41470cd1328cdb67c76732
Author: Marek Olšák <[email protected]> Date: Sat May 8 03:39:35 2010 +0200 r300/compiler: make shadow sampler codegen more readable, add comments --- .../drivers/dri/r300/compiler/radeon_program_tex.c | 44 ++++++++++++------- 1 files changed, 28 insertions(+), 16 deletions(-) diff --git a/src/mesa/drivers/dri/r300/compiler/radeon_program_tex.c b/src/mesa/drivers/dri/r300/compiler/radeon_program_tex.c index 98e391a..e1bb7c7 100644 --- a/src/mesa/drivers/dri/r300/compiler/radeon_program_tex.c +++ b/src/mesa/drivers/dri/r300/compiler/radeon_program_tex.c @@ -116,45 +116,53 @@ int radeonTransformTEX( struct rc_instruction * inst_rcp = rc_insert_new_instruction(c, inst); struct rc_instruction * inst_mad = rc_insert_new_instruction(c, inst_rcp); struct rc_instruction * inst_cmp = rc_insert_new_instruction(c, inst_mad); + unsigned tmp_recip_w = rc_find_free_temporary(c); + unsigned tmp_texsample = rc_find_free_temporary(c); + unsigned tmp_sum = rc_find_free_temporary(c); int pass, fail; + /* Save the output register. */ + struct rc_dst_register output_reg = inst->U.I.DstReg; + + /* Redirect TEX to a new temp. */ + inst->U.I.DstReg.File = RC_FILE_TEMPORARY; + inst->U.I.DstReg.Index = tmp_texsample; + inst->U.I.DstReg.WriteMask = RC_MASK_XYZW; + + /* Compute 1/W. */ inst_rcp->U.I.Opcode = RC_OPCODE_RCP; inst_rcp->U.I.DstReg.File = RC_FILE_TEMPORARY; - inst_rcp->U.I.DstReg.Index = rc_find_free_temporary(c); + inst_rcp->U.I.DstReg.Index = tmp_recip_w; inst_rcp->U.I.DstReg.WriteMask = RC_MASK_W; inst_rcp->U.I.SrcReg[0] = inst->U.I.SrcReg[0]; inst_rcp->U.I.SrcReg[0].Swizzle = RC_SWIZZLE_WWWW; - inst_cmp->U.I.DstReg = inst->U.I.DstReg; - inst->U.I.DstReg.File = RC_FILE_TEMPORARY; - inst->U.I.DstReg.Index = rc_find_free_temporary(c); - inst->U.I.DstReg.WriteMask = RC_MASK_XYZW; - + /* Perspective-divide r (=depth) by W and add the texture sample (see below). */ inst_mad->U.I.Opcode = RC_OPCODE_MAD; inst_mad->U.I.DstReg.File = RC_FILE_TEMPORARY; - inst_mad->U.I.DstReg.Index = rc_find_free_temporary(c); + inst_mad->U.I.DstReg.Index = tmp_sum; inst_mad->U.I.SrcReg[0] = inst->U.I.SrcReg[0]; inst_mad->U.I.SrcReg[0].Swizzle = RC_SWIZZLE_ZZZZ; inst_mad->U.I.SrcReg[1].File = RC_FILE_TEMPORARY; - inst_mad->U.I.SrcReg[1].Index = inst_rcp->U.I.DstReg.Index; + inst_mad->U.I.SrcReg[1].Index = tmp_recip_w; inst_mad->U.I.SrcReg[1].Swizzle = RC_SWIZZLE_WWWW; inst_mad->U.I.SrcReg[2].File = RC_FILE_TEMPORARY; - inst_mad->U.I.SrcReg[2].Index = inst->U.I.DstReg.Index; + inst_mad->U.I.SrcReg[2].Index = tmp_texsample; inst_mad->U.I.SrcReg[2].Swizzle = compiler->state.unit[inst->U.I.TexSrcUnit].depth_texture_swizzle; /* Recall that SrcReg[0] is tex, SrcReg[2] is r and: - * r < tex <=> -tex+r < 0 - * r >= tex <=> not (-tex+r < 0 */ + * LESS: r < tex <=> -tex+r < 0 + * GEQUAL: r >= tex <=> not (-tex+r < 0) + * GREATER: r > tex <=> tex-r < 0 + * LEQUAL: r <= tex <=> not ( tex-r < 0) + * + * This negates either r or tex: */ if (comparefunc == RC_COMPARE_FUNC_LESS || comparefunc == RC_COMPARE_FUNC_GEQUAL) inst_mad->U.I.SrcReg[2].Negate = inst_mad->U.I.SrcReg[2].Negate ^ RC_MASK_XYZW; else inst_mad->U.I.SrcReg[0].Negate = inst_mad->U.I.SrcReg[0].Negate ^ RC_MASK_XYZW; - inst_cmp->U.I.Opcode = RC_OPCODE_CMP; - /* DstReg has been filled out above */ - inst_cmp->U.I.SrcReg[0].File = RC_FILE_TEMPORARY; - inst_cmp->U.I.SrcReg[0].Index = inst_mad->U.I.DstReg.Index; - + /* This negates the whole expresion: */ if (comparefunc == RC_COMPARE_FUNC_LESS || comparefunc == RC_COMPARE_FUNC_GREATER) { pass = 1; fail = 2; @@ -163,6 +171,10 @@ int radeonTransformTEX( fail = 1; } + inst_cmp->U.I.Opcode = RC_OPCODE_CMP; + inst_cmp->U.I.DstReg = output_reg; + inst_cmp->U.I.SrcReg[0].File = RC_FILE_TEMPORARY; + inst_cmp->U.I.SrcReg[0].Index = tmp_sum; inst_cmp->U.I.SrcReg[pass].File = RC_FILE_NONE; inst_cmp->U.I.SrcReg[pass].Swizzle = RC_SWIZZLE_1111; inst_cmp->U.I.SrcReg[fail] = shadow_ambient(compiler, inst->U.I.TexSrcUnit); _______________________________________________ mesa-commit mailing list [email protected] http://lists.freedesktop.org/mailman/listinfo/mesa-commit
