From 4e9c3bbc60c2dd491ca45d3a5e0b9e156b1bc225 Mon Sep 17 00:00:00 2001 From: Brian Paul Date: Mon, 10 May 2010 13:46:39 -0600 Subject: [PATCH] st/mesa: rename vars, added comments --- src/mesa/state_tracker/st_mesa_to_tgsi.c | 76 +++++++++++++++++------- 1 file changed, 55 insertions(+), 21 deletions(-) diff --git a/src/mesa/state_tracker/st_mesa_to_tgsi.c b/src/mesa/state_tracker/st_mesa_to_tgsi.c index d7c280b21b3..6df6cdfe03d 100644 --- a/src/mesa/state_tracker/st_mesa_to_tgsi.c +++ b/src/mesa/state_tracker/st_mesa_to_tgsi.c @@ -62,10 +62,12 @@ struct st_translate { struct ureg_src inputs[PIPE_MAX_SHADER_INPUTS]; struct ureg_dst address[1]; struct ureg_src samplers[PIPE_MAX_SAMPLERS]; - struct ureg_dst psizregreal; - struct ureg_src pointSizeConst; - GLint psizoutindex; - GLboolean prevInstWrotePsiz; + + /* Extra info for handling point size clamping in vertex shader */ + struct ureg_dst pointSizeResult; /**< Actual point size output register */ + struct ureg_src pointSizeConst; /**< Point size range constant register */ + GLint pointSizeOutIndex; /**< Temp point size output register */ + GLboolean prevInstWrotePointSize; const GLuint *inputMapping; const GLuint *outputMapping; @@ -92,6 +94,12 @@ struct st_translate { }; +/** + * Make note of a branch to a label in the TGSI code. + * After we've emitted all instructions, we'll go over the list + * of labels built here and patch the TGSI code with the actual + * location of each label. + */ static unsigned *get_label( struct st_translate *t, unsigned branch_target ) { @@ -116,6 +124,12 @@ static unsigned *get_label( struct st_translate *t, } +/** + * Called prior to emitting the TGSI code for each Mesa instruction. + * Allocate additional space for instructions if needed. + * Update the insn[] array so the next Mesa instruction points to + * the next TGSI instruction. + */ static void set_insn_start( struct st_translate *t, unsigned start ) { @@ -135,8 +149,8 @@ static void set_insn_start( struct st_translate *t, } -/* - * Map mesa register file to TGSI register file. +/** + * Map a Mesa dst register to a TGSI ureg_dst register. */ static struct ureg_dst dst_register( struct st_translate *t, @@ -155,7 +169,7 @@ dst_register( struct st_translate *t, case PROGRAM_OUTPUT: if (t->procType == TGSI_PROCESSOR_VERTEX && index == VERT_RESULT_PSIZ) - t->prevInstWrotePsiz = GL_TRUE; + t->prevInstWrotePointSize = GL_TRUE; if (t->procType == TGSI_PROCESSOR_VERTEX) assert(index < VERT_RESULT_MAX); @@ -178,6 +192,9 @@ dst_register( struct st_translate *t, } +/** + * Map a Mesa src register to a TGSI ureg_src register. + */ static struct ureg_src src_register( struct st_translate *t, gl_register_file file, @@ -254,6 +271,9 @@ translate_texture_target( GLuint textarget, } +/** + * Create a TGSI ureg_dst register from a Mesa dest register. + */ static struct ureg_dst translate_dst( struct st_translate *t, const struct prog_dst_register *DstReg, @@ -276,6 +296,9 @@ translate_dst( struct st_translate *t, } +/** + * Create a TGSI ureg_src register from a Mesa src register. + */ static struct ureg_src translate_src( struct st_translate *t, const struct prog_src_register *SrcReg ) @@ -685,6 +708,7 @@ compile_instruction( } } + /** * Emit the TGSI instructions to adjust the WPOS pixel center convention */ @@ -696,12 +720,14 @@ emit_adjusted_wpos( struct st_translate *t, struct ureg_dst wpos_temp = ureg_DECL_temporary(ureg); struct ureg_src wpos_input = t->inputs[t->inputMapping[FRAG_ATTRIB_WPOS]]; - ureg_ADD(ureg, ureg_writemask(wpos_temp, TGSI_WRITEMASK_X | TGSI_WRITEMASK_Y), - wpos_input, ureg_imm1f(ureg, value)); + ureg_ADD(ureg, + ureg_writemask(wpos_temp, TGSI_WRITEMASK_X | TGSI_WRITEMASK_Y), + wpos_input, ureg_imm1f(ureg, value)); t->inputs[t->inputMapping[FRAG_ATTRIB_WPOS]] = ureg_src(wpos_temp); } + /** * Emit the TGSI instructions for inverting the WPOS y coordinate. */ @@ -894,8 +920,8 @@ st_translate_mesa_program( t->inputMapping = inputMapping; t->outputMapping = outputMapping; t->ureg = ureg; - t->psizoutindex = -1; - t->prevInstWrotePsiz = GL_FALSE; + t->pointSizeOutIndex = -1; + t->prevInstWrotePointSize = GL_FALSE; /*_mesa_print_program(program);*/ @@ -964,6 +990,9 @@ st_translate_mesa_program( outputSemanticName[i], outputSemanticIndex[i] ); if ((outputSemanticName[i] == TGSI_SEMANTIC_PSIZE) && program->Id) { + /* Writing to the point size result register requires special + * handling to implement clamping. + */ static const gl_state_index pointSizeClampState[STATE_LENGTH] = { STATE_INTERNAL, STATE_POINT_SIZE_IMPL_CLAMP, 0, 0, 0 }; /* XXX: note we are modifying the incoming shader here! Need to @@ -975,8 +1004,8 @@ st_translate_mesa_program( pointSizeClampState); struct ureg_dst psizregtemp = ureg_DECL_temporary( ureg ); t->pointSizeConst = ureg_DECL_constant( ureg, pointSizeClampConst ); - t->psizregreal = t->outputs[i]; - t->psizoutindex = i; + t->pointSizeResult = t->outputs[i]; + t->pointSizeOutIndex = i; t->outputs[i] = psizregtemp; } } @@ -1045,19 +1074,24 @@ st_translate_mesa_program( set_insn_start( t, ureg_get_instruction_number( ureg )); compile_instruction( t, &program->Instructions[i] ); - /* note can't do that easily at the end of prog due to - possible early return */ - if (t->prevInstWrotePsiz && program->Id) { + if (t->prevInstWrotePointSize && program->Id) { + /* The previous instruction wrote to the (fake) vertex point size + * result register. Now we need to clamp that value to the min/max + * point size range, putting the result into the real point size + * register. + * Note that we can't do this easily at the end of program due to + * possible early return. + */ set_insn_start( t, ureg_get_instruction_number( ureg )); ureg_MAX( t->ureg, - ureg_writemask(t->outputs[t->psizoutindex], WRITEMASK_X), - ureg_src(t->outputs[t->psizoutindex]), + ureg_writemask(t->outputs[t->pointSizeOutIndex], WRITEMASK_X), + ureg_src(t->outputs[t->pointSizeOutIndex]), ureg_swizzle(t->pointSizeConst, 1,1,1,1)); - ureg_MIN( t->ureg, ureg_writemask(t->psizregreal, WRITEMASK_X), - ureg_src(t->outputs[t->psizoutindex]), + ureg_MIN( t->ureg, ureg_writemask(t->pointSizeResult, WRITEMASK_X), + ureg_src(t->outputs[t->pointSizeOutIndex]), ureg_swizzle(t->pointSizeConst, 2,2,2,2)); } - t->prevInstWrotePsiz = GL_FALSE; + t->prevInstWrotePointSize = GL_FALSE; } /* Fix up all emitted labels: -- 2.30.2