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authorBrian Paul <brian.paul@tungstengraphics.com>2006-10-28 17:14:47 +0000
committerBrian Paul <brian.paul@tungstengraphics.com>2006-10-28 17:14:47 +0000
commitf5eea0cc7a8c568b00035427294812712c6c6081 (patch)
tree5123c64cbd98bc81f6c0a44f377ea6a2420c0628 /src/mesa
parentdb5529573f40c5ad68d589ab6a5e4e47d6743b4c (diff)
Implement _mesa_append_fog_code() for fragment program fog options.
Diffstat (limited to 'src/mesa')
-rw-r--r--src/mesa/shader/programopt.c195
-rw-r--r--src/mesa/shader/programopt.h2
2 files changed, 178 insertions, 19 deletions
diff --git a/src/mesa/shader/programopt.c b/src/mesa/shader/programopt.c
index 199202edf7..55991dcce3 100644
--- a/src/mesa/shader/programopt.c
+++ b/src/mesa/shader/programopt.c
@@ -1,6 +1,6 @@
/*
* Mesa 3-D graphics library
- * Version: 6.5.1
+ * Version: 6.5.2
*
* Copyright (C) 1999-2006 Brian Paul All Rights Reserved.
*
@@ -117,31 +117,190 @@ _mesa_insert_mvp_code(GLcontext *ctx, struct gl_vertex_program *vprog)
/**
* Append extra instructions onto the given fragment program to implement
- * the fog mode specified by program->FogOption.
- * XXX incomplete.
+ * the fog mode specified by fprog->FogOption.
+ * The fragment.fogcoord input is used to compute the fog blend factor.
+ *
+ * XXX with a little work, this function could be adapted to add fog code
+ * to vertex programs too.
*/
void
_mesa_append_fog_code(GLcontext *ctx, struct gl_fragment_program *fprog)
{
- struct prog_instruction newInst[10];
-
- switch (fprog->FogOption) {
- case GL_LINEAR:
- /* lerp */
- break;
- case GL_EXP:
- break;
- case GL_EXP2:
- break;
- case GL_NONE:
- /* no-op */
+ static const GLint fogParamsState[] = { STATE_FOG_PARAMS, 0, 0, 0, 0 };
+ static const GLint fogColorState[] = { STATE_FOG_COLOR, 0, 0, 0, 0 };
+ struct prog_instruction *newInst, *inst;
+ const GLuint origLen = fprog->Base.NumInstructions;
+ const GLuint newLen = origLen + 6;
+ GLuint i;
+ GLint fogParamsRef, fogColorRef; /* state references */
+ GLuint colorTemp, fogFactorTemp; /* temporary registerss */
+ GLfloat fogVals[4];
+ GLuint fogConsts; /* constant values for EXP, EXP2 mode */
+
+ if (fprog->FogOption != GL_NONE) {
+ _mesa_problem(ctx, "_mesa_append_fog_code() called for fragment program"
+ " with FogOption == GL_NONE");
return;
- default:
- _mesa_problem(ctx, "Invalid fog option");
+ }
+
+ /* Alloc storage for new instructions */
+ newInst = _mesa_alloc_instructions(newLen);
+ if (!newInst) {
+ _mesa_error(ctx, GL_OUT_OF_MEMORY,
+ "glProgramString(inserting fog_option code)");
return;
}
+ /* Copy orig instructions into new instruction buffer */
+ _mesa_memcpy(newInst, fprog->Base.Instructions,
+ origLen * sizeof(struct prog_instruction));
+
+ /* PARAM fogParamsRef = state.fog.params; */
+ fogParamsRef
+ = _mesa_add_state_reference(fprog->Base.Parameters, fogParamsState);
+ /* PARAM fogColorRef = state.fog.color; */
+ fogColorRef
+ = _mesa_add_state_reference(fprog->Base.Parameters, fogColorState);
- (void) newInst;
+ /* TEMP colorTemp; */
+ colorTemp = fprog->Base.NumTemporaries++;
+ /* TEMP fogFactorTemp; */
+ fogFactorTemp = fprog->Base.NumTemporaries++;
+ /* PARAM fogVals = { 1/ln(2), 1/sqrt(ln(2), 0, 0 }; */
+ fogVals[0] = 1.0 / log(2.0);
+ fogVals[1] = 1.0 / SQRTF(log(2.0));
+ fogVals[2] = 0.0;
+ fogVals[3] = 0.0;
+ fogConsts = _mesa_add_unnamed_constant(fprog->Base.Parameters, fogVals);
+
+ /* Scan program to find where result.color is written */
+ inst = newInst;
+ for (i = 0; i < fprog->Base.NumInstructions; i++) {
+ if (inst->Opcode == OPCODE_END)
+ break;
+ if (inst->DstReg.File == PROGRAM_OUTPUT &&
+ inst->DstReg.Index == FRAG_RESULT_COLR) {
+ /* change the instruction to write to colorTemp w/ clamping */
+ inst->DstReg.File = PROGRAM_TEMPORARY;
+ inst->DstReg.Index = colorTemp;
+ inst->SaturateMode = SATURATE_ZERO_ONE;
+ /* don't break (may be several writes to result.color) */
+ }
+ inst++;
+ }
+ assert(inst->Opcode == OPCODE_END); /* we'll overwrite this inst */
+
+ for (i = 0; i < 6; i++)
+ _mesa_init_instruction(inst + i);
+
+ /* emit instructions to compute fog blending factor */
+ if (fprog->FogOption == GL_LINEAR) {
+ /* SUB fogFactorTemp.x, fogParamsRef.z, fragment.fogcoord.x; */
+ inst->Opcode = OPCODE_SUB;
+ inst->DstReg.File = PROGRAM_TEMPORARY;
+ inst->DstReg.Index = fogFactorTemp;
+ inst->DstReg.WriteMask = WRITEMASK_X;
+ inst->SrcReg[0].File = PROGRAM_STATE_VAR;
+ inst->SrcReg[0].Index = fogParamsRef;
+ inst->SrcReg[0].Swizzle = SWIZZLE_Z;
+ inst->SrcReg[1].File = PROGRAM_INPUT;
+ inst->SrcReg[1].Index = FRAG_ATTRIB_FOGC;
+ inst++;
+ /* MUL fogFactorTemp.x, fogFactorTemp, fogParamsRef.w; */
+ inst->Opcode = OPCODE_MUL;
+ inst->DstReg.File = PROGRAM_TEMPORARY;
+ inst->DstReg.Index = fogFactorTemp;
+ inst->DstReg.WriteMask = WRITEMASK_X;
+ inst->SrcReg[0].File = PROGRAM_TEMPORARY;
+ inst->SrcReg[0].Index = fogFactorTemp;
+ inst->SrcReg[1].File = PROGRAM_STATE_VAR;
+ inst->SrcReg[1].Index = fogParamsRef;
+ inst->SrcReg[1].Swizzle = SWIZZLE_W;
+ inst++;
+ }
+ else {
+ ASSERT(fprog->FogOption == GL_EXP || fprog->FogOption == GL_EXP2);
+ /* MUL fogFactorTemp.x, fogParamsRef.x, fragment.fogcoord; */
+ inst->Opcode = OPCODE_MUL;
+ inst->DstReg.File = PROGRAM_TEMPORARY;
+ inst->DstReg.Index = fogFactorTemp;
+ inst->DstReg.WriteMask = WRITEMASK_X;
+ inst->SrcReg[0].File = PROGRAM_STATE_VAR;
+ inst->SrcReg[0].Index = fogParamsRef;
+ inst->SrcReg[0].Swizzle = SWIZZLE_X; /* X=density */
+ inst->SrcReg[1].File = PROGRAM_INPUT;
+ inst->SrcReg[1].Index = FRAG_ATTRIB_FOGC;
+ inst->SrcReg[1].Swizzle = SWIZZLE_X;
+ inst++;
+ if (fprog->FogOption == GL_EXP2) {
+ /* MUL fogFactorTemp.x, fogFactorTemp.x, fogFactorTemp.x; */
+ inst->Opcode = OPCODE_MUL;
+ inst->DstReg.File = PROGRAM_TEMPORARY;
+ inst->DstReg.Index = fogFactorTemp;
+ inst->DstReg.WriteMask = WRITEMASK_X;
+ inst->SrcReg[0].File = PROGRAM_TEMPORARY;
+ inst->SrcReg[0].Index = fogFactorTemp;
+ inst->SrcReg[1].File = PROGRAM_TEMPORARY;
+ inst->SrcReg[1].Index = fogFactorTemp;
+ inst++;
+ }
+ /* EXP: MUL fogFactorTemp.x, fogFactorTemp.x, {1/ln(2)}; */
+ /* EXP2: MUL fogFactorTemp.x, fogFactorTemp.x, {1/sqrt(ln(2))}; */
+ inst->Opcode = OPCODE_MUL;
+ inst->DstReg.File = PROGRAM_TEMPORARY;
+ inst->DstReg.Index = fogFactorTemp;
+ inst->DstReg.WriteMask = WRITEMASK_X;
+ inst->SrcReg[0].File = PROGRAM_TEMPORARY;
+ inst->SrcReg[0].Index = fogFactorTemp;
+ inst->SrcReg[1].File = PROGRAM_CONSTANT;
+ inst->SrcReg[1].Index = fogConsts;
+ inst->SrcReg[1].Swizzle
+ = (fprog->FogOption == GL_EXP) ? SWIZZLE_X : SWIZZLE_Y;
+ inst++;
+ /* EX2_SAT fogFactorTemp.x, -fogFactorTemp.x; */
+ inst->Opcode = OPCODE_EX2;
+ inst->DstReg.File = PROGRAM_TEMPORARY;
+ inst->DstReg.Index = fogFactorTemp;
+ inst->DstReg.WriteMask = WRITEMASK_X;
+ inst->SrcReg[0].File = PROGRAM_TEMPORARY;
+ inst->SrcReg[0].Index = fogFactorTemp;
+ inst->SrcReg[0].NegateBase = GL_TRUE;
+ inst->SaturateMode = SATURATE_ZERO_ONE;
+ inst++;
+ }
+ /* LRP result.color.xyz, fogFactorTemp.xxxx, colorTemp, fogColorRef; */
+ inst->Opcode = OPCODE_LRP;
+ inst->DstReg.File = PROGRAM_OUTPUT;
+ inst->DstReg.Index = FRAG_RESULT_COLR;
+ inst->DstReg.WriteMask = WRITEMASK_XYZ;
+ inst->SrcReg[0].File = PROGRAM_TEMPORARY;
+ inst->SrcReg[0].Index = fogFactorTemp;
+ inst->SrcReg[0].Swizzle
+ = MAKE_SWIZZLE4(SWIZZLE_X, SWIZZLE_X, SWIZZLE_X, SWIZZLE_X);
+ inst->SrcReg[1].File = PROGRAM_TEMPORARY;
+ inst->SrcReg[1].Index = colorTemp;
+ inst->SrcReg[2].File = PROGRAM_STATE_VAR;
+ inst->SrcReg[2].Index = fogColorRef;
+ inst++;
+ /* MOV result.color.w, colorTemp.x; # copy alpha */
+ inst->Opcode = OPCODE_MOV;
+ inst->DstReg.File = PROGRAM_OUTPUT;
+ inst->DstReg.Index = FRAG_RESULT_COLR;
+ inst->DstReg.WriteMask = WRITEMASK_W;
+ inst->SrcReg[0].File = PROGRAM_TEMPORARY;
+ inst->SrcReg[0].Index = colorTemp;
+ inst++;
+ /* END; */
+ inst->Opcode = OPCODE_END;
+ inst++;
+
+ /* free old instructions */
+ _mesa_free(fprog->Base.Instructions);
+
+ /* install new instructions */
+ fprog->Base.Instructions = newInst;
+ fprog->Base.NumInstructions = inst - newInst;
+ fprog->Base.InputsRead |= FRAG_BIT_FOGC;
+ /* XXX do this? fprog->FogOption = GL_NONE; */
}
diff --git a/src/mesa/shader/programopt.h b/src/mesa/shader/programopt.h
index 8799da435b..efaf29b937 100644
--- a/src/mesa/shader/programopt.h
+++ b/src/mesa/shader/programopt.h
@@ -1,6 +1,6 @@
/*
* Mesa 3-D graphics library
- * Version: 6.5.1
+ * Version: 6.5.2
*
* Copyright (C) 1999-2006 Brian Paul All Rights Reserved.
*