src/mesa/shader/programopt.c

   1 /*
   2  * Mesa 3-D graphics library
   3  * Version:  6.5.2
   4  *
   5  * Copyright (C) 1999-2006  Brian Paul   All Rights Reserved.
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining a
   8  * copy of this software and associated documentation files (the "Software"),
   9  * to deal in the Software without restriction, including without limitation
  10  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  11  * and/or sell copies of the Software, and to permit persons to whom the
  12  * Software is furnished to do so, subject to the following conditions:
  13  *
  14  * The above copyright notice and this permission notice shall be included
  15  * in all copies or substantial portions of the Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  18  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  20  * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
  21  * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  22  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  23  */
  24
  25 /**
  26  * \file  programopt.c
  27  * Vertex/Fragment program optimizations and transformations for program
  28  * options, etc.
  29  *
  30  * \author Brian Paul
  31  */
  32
  33
  34 #include "glheader.h"
  35 #include "context.h"
  36 #include "imports.h"
  37 #include "mtypes.h"
  38 #include "program.h"
  39 #include "programopt.h"
  40 #include "program_instruction.h"
  41
  42
  43 /**
  44  * This function inserts instructions for coordinate modelview * projection
  45  * into a vertex program.
  46  * May be used to implement the position_invariant option.
  47  */
  48 void
  49 _mesa_insert_mvp_code(GLcontext *ctx, struct gl_vertex_program *vprog)
  50 {
  51    struct prog_instruction *newInst;
  52    const GLuint origLen = vprog->Base.NumInstructions;
  53    const GLuint newLen = origLen + 4;
  54    GLuint i;
  55
  56    /*
  57     * Setup state references for the modelview/projection matrix.
  58     * XXX we should check if these state vars are already declared.
  59     */
  60    static const GLint mvpState[4][5] = {
  61       { STATE_MATRIX, STATE_MVP, 0, 0, 0 },  /* state.matrix.mvp.row[0] */
  62       { STATE_MATRIX, STATE_MVP, 0, 1, 1 },  /* state.matrix.mvp.row[1] */
  63       { STATE_MATRIX, STATE_MVP, 0, 2, 2 },  /* state.matrix.mvp.row[2] */
  64       { STATE_MATRIX, STATE_MVP, 0, 3, 3 },  /* state.matrix.mvp.row[3] */
  65    };
  66    GLint mvpRef[4];
  67
  68    for (i = 0; i < 4; i++) {
  69       mvpRef[i] = _mesa_add_state_reference(vprog->Base.Parameters,
  70                                             mvpState[i]);
  71    }
  72
  73    /* Alloc storage for new instructions */
  74    newInst = _mesa_alloc_instructions(newLen);
  75    if (!newInst) {
  76       _mesa_error(ctx, GL_OUT_OF_MEMORY,
  77                   "glProgramString(inserting position_invariant code)");
  78       return;
  79    }
  80
  81    /*
  82     * Generated instructions:
  83     * newInst[0] = DP4 result.position.x, mvp.row[0], vertex.position;
  84     * newInst[1] = DP4 result.position.y, mvp.row[1], vertex.position;
  85     * newInst[2] = DP4 result.position.z, mvp.row[2], vertex.position;
  86     * newInst[3] = DP4 result.position.w, mvp.row[3], vertex.position;
  87     */
  88    _mesa_init_instructions(newInst, 4);
  89    for (i = 0; i < 4; i++) {
  90       newInst[i].Opcode = OPCODE_DP4;
  91       newInst[i].DstReg.File = PROGRAM_OUTPUT;
  92       newInst[i].DstReg.Index = VERT_RESULT_HPOS;
  93       newInst[i].DstReg.WriteMask = (WRITEMASK_X << i);
  94       newInst[i].SrcReg[0].File = PROGRAM_STATE_VAR;
  95       newInst[i].SrcReg[0].Index = mvpRef[i];
  96       newInst[i].SrcReg[0].Swizzle = SWIZZLE_NOOP;
  97       newInst[i].SrcReg[1].File = PROGRAM_INPUT;
  98       newInst[i].SrcReg[1].Index = VERT_ATTRIB_POS;
  99       newInst[i].SrcReg[1].Swizzle = SWIZZLE_NOOP;
 100    }
 101
 102    /* Append original instructions after new instructions */
 103    _mesa_copy_instructions (newInst + 4, vprog->Base.Instructions, origLen);
 104
 105    /* free old instructions */
 106    _mesa_free(vprog->Base.Instructions);
 107
 108    /* install new instructions */
 109    vprog->Base.Instructions = newInst;
 110    vprog->Base.NumInstructions = newLen;
 111    vprog->Base.InputsRead |= VERT_BIT_POS;
 112    vprog->Base.OutputsWritten |= (1 << VERT_RESULT_HPOS);
 113 }
 114
 115
 116
 117 /**
 118  * Append extra instructions onto the given fragment program to implement
 119  * the fog mode specified by fprog->FogOption.
 120  * The fragment.fogcoord input is used to compute the fog blend factor.
 121  *
 122  * XXX with a little work, this function could be adapted to add fog code
 123  * to vertex programs too.
 124  */
 125 void
 126 _mesa_append_fog_code(GLcontext *ctx, struct gl_fragment_program *fprog)
 127 {
 128    static const GLint fogPStateOpt[] = { STATE_INTERNAL,
 129                                          STATE_FOG_PARAMS_OPTIMIZED, 0, 0, 0 };
 130    static const GLint fogColorState[] = { STATE_FOG_COLOR, 0, 0, 0, 0 };
 131    struct prog_instruction *newInst, *inst;
 132    const GLuint origLen = fprog->Base.NumInstructions;
 133    const GLuint newLen = origLen + 5;
 134    GLuint i;
 135    GLint fogPRefOpt, fogColorRef; /* state references */
 136    GLuint colorTemp, fogFactorTemp; /* temporary registerss */
 137
 138    if (fprog->FogOption == GL_NONE) {
 139       _mesa_problem(ctx, "_mesa_append_fog_code() called for fragment program"
 140                     " with FogOption == GL_NONE");
 141       return;
 142    }
 143
 144    /* Alloc storage for new instructions */
 145    newInst = _mesa_alloc_instructions(newLen);
 146    if (!newInst) {
 147       _mesa_error(ctx, GL_OUT_OF_MEMORY,
 148                   "glProgramString(inserting fog_option code)");
 149       return;
 150    }
 151
 152    /* Copy orig instructions into new instruction buffer */
 153    _mesa_memcpy(newInst, fprog->Base.Instructions,
 154                 origLen * sizeof(struct prog_instruction));
 155
 156    /* PARAM fogParamsRefOpt = internal optimized fog params; */
 157    fogPRefOpt
 158       = _mesa_add_state_reference(fprog->Base.Parameters, fogPStateOpt);
 159    /* PARAM fogColorRef = state.fog.color; */
 160    fogColorRef
 161       = _mesa_add_state_reference(fprog->Base.Parameters, fogColorState);
 162
 163    /* TEMP colorTemp; */
 164    colorTemp = fprog->Base.NumTemporaries++;
 165    /* TEMP fogFactorTemp; */
 166    fogFactorTemp = fprog->Base.NumTemporaries++;
 167
 168    /* Scan program to find where result.color is written */
 169    inst = newInst;
 170    for (i = 0; i < fprog->Base.NumInstructions; i++) {
 171       if (inst->Opcode == OPCODE_END)
 172          break;
 173       if (inst->DstReg.File == PROGRAM_OUTPUT &&
 174           inst->DstReg.Index == FRAG_RESULT_COLR) {
 175          /* change the instruction to write to colorTemp w/ clamping */
 176          inst->DstReg.File = PROGRAM_TEMPORARY;
 177          inst->DstReg.Index = colorTemp;
 178          inst->SaturateMode = SATURATE_ZERO_ONE;
 179          /* don't break (may be several writes to result.color) */
 180       }
 181       inst++;
 182    }
 183    assert(inst->Opcode == OPCODE_END); /* we'll overwrite this inst */
 184
 185    _mesa_init_instructions(inst, 5);
 186
 187    /* emit instructions to compute fog blending factor */
 188    if (fprog->FogOption == GL_LINEAR) {
 189       /* MAD fogFactorTemp.x, fragment.fogcoord.x, fogPRefOpt.x, fogPRefOpt.y; */
 190       inst->Opcode = OPCODE_MAD;
 191       inst->DstReg.File = PROGRAM_TEMPORARY;
 192       inst->DstReg.Index = fogFactorTemp;
 193       inst->DstReg.WriteMask = WRITEMASK_X;
 194       inst->SrcReg[0].File = PROGRAM_INPUT;
 195       inst->SrcReg[0].Index = FRAG_ATTRIB_FOGC;
 196       inst->SrcReg[0].Swizzle = SWIZZLE_X;
 197       inst->SrcReg[1].File = PROGRAM_STATE_VAR;
 198       inst->SrcReg[1].Index = fogPRefOpt;
 199       inst->SrcReg[1].Swizzle = SWIZZLE_X;
 200       inst->SrcReg[2].File = PROGRAM_STATE_VAR;
 201       inst->SrcReg[2].Index = fogPRefOpt;
 202       inst->SrcReg[2].Swizzle = SWIZZLE_Y;
 203       inst++;
 204    }
 205    else {
 206       ASSERT(fprog->FogOption == GL_EXP || fprog->FogOption == GL_EXP2);
 207       /* fogPRefOpt.z = d/ln(2), fogPRefOpt.w = d/sqrt(ln(2) */
 208       /* EXP: MUL fogFactorTemp.x, fogPRefOpt.z, fragment.fogcoord.x; */
 209       /* EXP2: MUL fogFactorTemp.x, fogPRefOpt.w, fragment.fogcoord.x; */
 210       inst->Opcode = OPCODE_MUL;
 211       inst->DstReg.File = PROGRAM_TEMPORARY;
 212       inst->DstReg.Index = fogFactorTemp;
 213       inst->DstReg.WriteMask = WRITEMASK_X;
 214       inst->SrcReg[0].File = PROGRAM_STATE_VAR;
 215       inst->SrcReg[0].Index = fogPRefOpt;
 216       inst->SrcReg[0].Swizzle
 217          = (fprog->FogOption == GL_EXP) ? SWIZZLE_Z : SWIZZLE_W;
 218       inst->SrcReg[1].File = PROGRAM_INPUT;
 219       inst->SrcReg[1].Index = FRAG_ATTRIB_FOGC;
 220       inst->SrcReg[1].Swizzle = SWIZZLE_X;
 221       inst++;
 222       if (fprog->FogOption == GL_EXP2) {
 223          /* MUL fogFactorTemp.x, fogFactorTemp.x, fogFactorTemp.x; */
 224          inst->Opcode = OPCODE_MUL;
 225          inst->DstReg.File = PROGRAM_TEMPORARY;
 226          inst->DstReg.Index = fogFactorTemp;
 227          inst->DstReg.WriteMask = WRITEMASK_X;
 228          inst->SrcReg[0].File = PROGRAM_TEMPORARY;
 229          inst->SrcReg[0].Index = fogFactorTemp;
 230          inst->SrcReg[0].Swizzle = SWIZZLE_X;
 231          inst->SrcReg[1].File = PROGRAM_TEMPORARY;
 232          inst->SrcReg[1].Index = fogFactorTemp;
 233          inst->SrcReg[1].Swizzle = SWIZZLE_X;
 234          inst++;
 235       }
 236       /* EX2_SAT fogFactorTemp.x, -fogFactorTemp.x; */
 237       inst->Opcode = OPCODE_EX2;
 238       inst->DstReg.File = PROGRAM_TEMPORARY;
 239       inst->DstReg.Index = fogFactorTemp;
 240       inst->DstReg.WriteMask = WRITEMASK_X;
 241       inst->SrcReg[0].File = PROGRAM_TEMPORARY;
 242       inst->SrcReg[0].Index = fogFactorTemp;
 243       inst->SrcReg[0].NegateBase = GL_TRUE;
 244       inst->SrcReg[0].Swizzle = SWIZZLE_X;
 245       inst->SaturateMode = SATURATE_ZERO_ONE;
 246       inst++;
 247    }
 248    /* LRP result.color.xyz, fogFactorTemp.xxxx, colorTemp, fogColorRef; */
 249    inst->Opcode = OPCODE_LRP;
 250    inst->DstReg.File = PROGRAM_OUTPUT;
 251    inst->DstReg.Index = FRAG_RESULT_COLR;
 252    inst->DstReg.WriteMask = WRITEMASK_XYZ;
 253    inst->SrcReg[0].File = PROGRAM_TEMPORARY;
 254    inst->SrcReg[0].Index = fogFactorTemp;
 255    inst->SrcReg[0].Swizzle
 256       = MAKE_SWIZZLE4(SWIZZLE_X, SWIZZLE_X, SWIZZLE_X, SWIZZLE_X);
 257    inst->SrcReg[1].File = PROGRAM_TEMPORARY;
 258    inst->SrcReg[1].Index = colorTemp;
 259    inst->SrcReg[1].Swizzle = SWIZZLE_NOOP;
 260    inst->SrcReg[2].File = PROGRAM_STATE_VAR;
 261    inst->SrcReg[2].Index = fogColorRef;
 262    inst->SrcReg[2].Swizzle = SWIZZLE_NOOP;
 263    inst++;
 264    /* MOV result.color.w, colorTemp.x;  # copy alpha */
 265    inst->Opcode = OPCODE_MOV;
 266    inst->DstReg.File = PROGRAM_OUTPUT;
 267    inst->DstReg.Index = FRAG_RESULT_COLR;
 268    inst->DstReg.WriteMask = WRITEMASK_W;
 269    inst->SrcReg[0].File = PROGRAM_TEMPORARY;
 270    inst->SrcReg[0].Index = colorTemp;
 271    inst->SrcReg[0].Swizzle = SWIZZLE_NOOP;
 272    inst++;
 273    /* END; */
 274    inst->Opcode = OPCODE_END;
 275    inst++;
 276
 277    /* free old instructions */
 278    _mesa_free(fprog->Base.Instructions);
 279
 280    /* install new instructions */
 281    fprog->Base.Instructions = newInst;
 282    fprog->Base.NumInstructions = inst - newInst;
 283    fprog->Base.InputsRead |= FRAG_BIT_FOGC;
 284    /* XXX do this?  fprog->FogOption = GL_NONE; */
 285 }