diff options
| author | Brian <brian.paul@tungstengraphics.com> | 2007-10-27 09:32:50 -0600 |
|---|---|---|
| committer | Brian <brian.paul@tungstengraphics.com> | 2007-10-27 09:32:50 -0600 |
| commit | 6ada4e3a69476ed086955fe4060b894559e1eb95 (patch) | |
| tree | 90f876131c359de27766c21bcf38fb0106d54519 /src/mesa/state_tracker/st_mesa_to_tgsi.c | |
| parent | f6a73c3f2815c4c84563c186bba6c8e67bb42ae9 (diff) | |
Comments about texture instructions and the src regs
Diffstat (limited to 'src/mesa/state_tracker/st_mesa_to_tgsi.c')
| -rw-r--r-- | src/mesa/state_tracker/st_mesa_to_tgsi.c | 13 |
1 files changed, 10 insertions, 3 deletions
diff --git a/src/mesa/state_tracker/st_mesa_to_tgsi.c b/src/mesa/state_tracker/st_mesa_to_tgsi.c index 131e50bece..621159eb85 100644 --- a/src/mesa/state_tracker/st_mesa_to_tgsi.c +++ b/src/mesa/state_tracker/st_mesa_to_tgsi.c @@ -459,6 +459,7 @@ compile_instruction( fullinst->Instruction.Opcode = TGSI_OPCODE_SWZ;
break;
case OPCODE_TEX:
+ /* ordinary texture lookup */
fullinst->Instruction.Opcode = TGSI_OPCODE_TEX;
fullinst->Instruction.NumSrcRegs = 2;
fullinst->InstructionExtTexture.Texture = map_texture_target( inst->TexSrcTarget );
@@ -466,6 +467,7 @@ compile_instruction( fullinst->FullSrcRegisters[1].SrcRegister.Index = inst->TexSrcUnit;
break;
case OPCODE_TXB:
+ /* texture lookup with LOD bias */
fullinst->Instruction.Opcode = TGSI_OPCODE_TXB;
fullinst->Instruction.NumSrcRegs = 2;
fullinst->InstructionExtTexture.Texture = map_texture_target( inst->TexSrcTarget );
@@ -473,13 +475,16 @@ compile_instruction( fullinst->FullSrcRegisters[1].SrcRegister.Index = inst->TexSrcUnit;
break;
case OPCODE_TXD:
+ /* texture lookup with explicit partial derivatives */
fullinst->Instruction.Opcode = TGSI_OPCODE_TXD;
- fullinst->Instruction.NumSrcRegs = 2;
+ fullinst->Instruction.NumSrcRegs = 4;
fullinst->InstructionExtTexture.Texture = map_texture_target( inst->TexSrcTarget );
- fullinst->FullSrcRegisters[1].SrcRegister.File = TGSI_FILE_SAMPLER;
- fullinst->FullSrcRegisters[1].SrcRegister.Index = inst->TexSrcUnit;
+ /* src[0] = coord, src[1] = d[strq]/dx, src[2] = d[strq]/dy */
+ fullinst->FullSrcRegisters[3].SrcRegister.File = TGSI_FILE_SAMPLER;
+ fullinst->FullSrcRegisters[3].SrcRegister.Index = inst->TexSrcUnit;
break;
case OPCODE_TXL:
+ /* texture lookup with explicit LOD */
fullinst->Instruction.Opcode = TGSI_OPCODE_TXL;
fullinst->Instruction.NumSrcRegs = 2;
fullinst->InstructionExtTexture.Texture = map_texture_target( inst->TexSrcTarget );
@@ -487,6 +492,8 @@ compile_instruction( fullinst->FullSrcRegisters[1].SrcRegister.Index = inst->TexSrcUnit;
break;
case OPCODE_TXP:
+ /* texture lookup with divide by Q component */
+ /* convert to TEX w/ special flag for division */
fullinst->Instruction.Opcode = TGSI_OPCODE_TEX;
fullinst->Instruction.NumSrcRegs = 2;
fullinst->InstructionExtTexture.Texture = map_texture_target( inst->TexSrcTarget );
|