diff options
Diffstat (limited to 'src/mesa/drivers/dri/r300/radeon_program_alu.c')
| -rw-r--r-- | src/mesa/drivers/dri/r300/radeon_program_alu.c | 52 |
1 files changed, 52 insertions, 0 deletions
diff --git a/src/mesa/drivers/dri/r300/radeon_program_alu.c b/src/mesa/drivers/dri/r300/radeon_program_alu.c index fa6a67f0c19..8daa94c7268 100644 --- a/src/mesa/drivers/dri/r300/radeon_program_alu.c +++ b/src/mesa/drivers/dri/r300/radeon_program_alu.c @@ -556,3 +556,55 @@ GLboolean radeonTransformTrigSimple(struct radeon_transform_context* t, return GL_TRUE; } + + +/** + * Transform the trigonometric functions COS, SIN, and SCS + * to include pre-scaling by 1/(2*PI) and taking the fractional + * part, so that the input to COS and SIN is always in the range [0,1). + * SCS is replaced by one COS and one SIN instruction. + * + * @warning This transformation implicitly changes the semantics of SIN and COS! + */ +GLboolean radeonTransformTrigScale(struct radeon_transform_context* t, + struct prog_instruction* inst, + void* unused) +{ + if (inst->Opcode != OPCODE_COS && + inst->Opcode != OPCODE_SIN && + inst->Opcode != OPCODE_SCS) + return GL_FALSE; + + static const GLfloat RCP_2PI[] = { 0.15915494309189535 }; + GLuint temp; + GLuint constant; + GLuint constant_swizzle; + + temp = radeonFindFreeTemporary(t); + constant = _mesa_add_unnamed_constant(t->Program->Parameters, RCP_2PI, 1, &constant_swizzle); + + emit2(t->Program, OPCODE_MUL, dstregtmpmask(temp, WRITEMASK_W), + swizzle(inst->SrcReg[0], SWIZZLE_X, SWIZZLE_X, SWIZZLE_X, SWIZZLE_X), + srcregswz(PROGRAM_CONSTANT, constant, constant_swizzle)); + emit1(t->Program, OPCODE_FRC, dstregtmpmask(temp, WRITEMASK_W), + srcreg(PROGRAM_TEMPORARY, temp)); + + if (inst->Opcode == OPCODE_COS) { + emit1(t->Program, OPCODE_COS, inst->DstReg, srcregswz(PROGRAM_TEMPORARY, temp, SWIZZLE_WWWW)); + } else if (inst->Opcode == OPCODE_SIN) { + emit1(t->Program, OPCODE_SIN, inst->DstReg, srcregswz(PROGRAM_TEMPORARY, temp, SWIZZLE_WWWW)); + } else if (inst->Opcode == OPCODE_SCS) { + struct prog_dst_register moddst = inst->DstReg; + + if (inst->DstReg.WriteMask & WRITEMASK_X) { + moddst.WriteMask = WRITEMASK_X; + emit1(t->Program, OPCODE_COS, moddst, srcregswz(PROGRAM_TEMPORARY, temp, SWIZZLE_WWWW)); + } + if (inst->DstReg.WriteMask & WRITEMASK_Y) { + moddst.WriteMask = WRITEMASK_Y; + emit1(t->Program, OPCODE_SIN, moddst, srcregswz(PROGRAM_TEMPORARY, temp, SWIZZLE_WWWW)); + } + } + + return GL_TRUE; +} |