summaryrefslogtreecommitdiffstats
path: root/src/mesa
diff options
context:
space:
mode:
authorBrian Paul <brianp@vmware.com>2010-05-10 13:46:39 -0600
committerBrian Paul <brianp@vmware.com>2010-05-10 17:04:19 -0600
commit4e9c3bbc60c2dd491ca45d3a5e0b9e156b1bc225 (patch)
tree34e52625561ef1475410aa0783d330a2ae5f1b5f /src/mesa
parent0bf1ddd60a3660974ad54e410533eeb481949364 (diff)
st/mesa: rename vars, added comments
Diffstat (limited to 'src/mesa')
-rw-r--r--src/mesa/state_tracker/st_mesa_to_tgsi.c76
1 files 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: