[Mesa-dev] [PATCH 2/2] st/mesa: add support for gl_ClipDistance
Bryan Cain
bryancain3 at gmail.com
Sat Dec 17 14:15:16 PST 2011
---
src/mesa/state_tracker/st_glsl_to_tgsi.cpp | 49 +++++++++++++++++++++++++---
src/mesa/state_tracker/st_program.c | 18 ++++++++++
2 files changed, 62 insertions(+), 5 deletions(-)
diff --git a/src/mesa/state_tracker/st_glsl_to_tgsi.cpp b/src/mesa/state_tracker/st_glsl_to_tgsi.cpp
index b929806..3e8df78 100644
--- a/src/mesa/state_tracker/st_glsl_to_tgsi.cpp
+++ b/src/mesa/state_tracker/st_glsl_to_tgsi.cpp
@@ -304,6 +304,7 @@ public:
int samplers_used;
bool indirect_addr_temps;
bool indirect_addr_consts;
+ int num_clip_distances;
int glsl_version;
bool native_integers;
@@ -4618,9 +4619,16 @@ st_translate_program(
}
for (i = 0; i < numOutputs; i++) {
- t->outputs[i] = ureg_DECL_output(ureg,
- outputSemanticName[i],
- outputSemanticIndex[i]);
+ if (outputSemanticName[i] == TGSI_SEMANTIC_CLIPDIST) {
+ int mask = ((1 << (program->num_clip_distances - 4*outputSemanticIndex[i])) - 1) & 0xf;
+ t->outputs[i] = ureg_DECL_output_masked(ureg,
+ outputSemanticName[i],
+ outputSemanticIndex[i],
+ mask);
+ } else
+ t->outputs[i] = ureg_DECL_output(ureg,
+ outputSemanticName[i],
+ outputSemanticIndex[i]);
if ((outputSemanticName[i] == TGSI_SEMANTIC_PSIZE) && proginfo->Id) {
/* Writing to the point size result register requires special
* handling to implement clamping.
@@ -4797,7 +4805,8 @@ out:
static struct gl_program *
get_mesa_program(struct gl_context *ctx,
struct gl_shader_program *shader_program,
- struct gl_shader *shader)
+ struct gl_shader *shader,
+ int num_clip_distances)
{
glsl_to_tgsi_visitor* v = new glsl_to_tgsi_visitor();
struct gl_program *prog;
@@ -4842,6 +4851,7 @@ get_mesa_program(struct gl_context *ctx,
v->options = options;
v->glsl_version = ctx->Const.GLSLVersion;
v->native_integers = ctx->Const.NativeIntegers;
+ v->num_clip_distances = num_clip_distances;
_mesa_generate_parameters_list_for_uniforms(shader_program, shader,
prog->Parameters);
@@ -4971,6 +4981,27 @@ get_mesa_program(struct gl_context *ctx,
return prog;
}
+/**
+ * Searches through the IR for a declaration of gl_ClipDistance and returns the
+ * declared size of the gl_ClipDistance array. Returns 0 if gl_ClipDistance is
+ * not declared in the IR.
+ */
+int get_clip_distance_size(exec_list *ir)
+{
+ foreach_iter (exec_list_iterator, iter, *ir) {
+ ir_instruction *inst = (ir_instruction *)iter.get();
+ ir_variable *var = inst->as_variable();
+ if (var == NULL) continue;
+ if (!strcmp(var->name, "gl_ClipDistance"))
+ {
+ fprintf(stderr, "gl_ClipDistance found with size %i\n", var->type->length);
+ return var->type->length;
+ }
+ }
+
+ return 0;
+}
+
extern "C" {
struct gl_shader *
@@ -5009,6 +5040,7 @@ st_new_shader_program(struct gl_context *ctx, GLuint name)
GLboolean
st_link_shader(struct gl_context *ctx, struct gl_shader_program *prog)
{
+ int num_clip_distances[MESA_SHADER_TYPES];
assert(prog->LinkStatus);
for (unsigned i = 0; i < MESA_SHADER_TYPES; i++) {
@@ -5020,6 +5052,11 @@ st_link_shader(struct gl_context *ctx, struct gl_shader_program *prog)
const struct gl_shader_compiler_options *options =
&ctx->ShaderCompilerOptions[_mesa_shader_type_to_index(prog->_LinkedShaders[i]->Type)];
+ /* We have to determine the length of the gl_ClipDistance array before
+ * the array is lowered to two vec4s by lower_clip_distance().
+ */
+ num_clip_distances[i] = get_clip_distance_size(ir);
+
do {
progress = false;
@@ -5036,6 +5073,7 @@ st_link_shader(struct gl_context *ctx, struct gl_shader_program *prog)
|| progress;
progress = lower_quadop_vector(ir, false) || progress;
+ progress = lower_clip_distance(ir) || progress;
if (options->MaxIfDepth == 0)
progress = lower_discard(ir) || progress;
@@ -5070,7 +5108,8 @@ st_link_shader(struct gl_context *ctx, struct gl_shader_program *prog)
if (prog->_LinkedShaders[i] == NULL)
continue;
- linked_prog = get_mesa_program(ctx, prog, prog->_LinkedShaders[i]);
+ linked_prog = get_mesa_program(ctx, prog, prog->_LinkedShaders[i],
+ num_clip_distances[i]);
if (linked_prog) {
static const GLenum targets[] = {
diff --git a/src/mesa/state_tracker/st_program.c b/src/mesa/state_tracker/st_program.c
index b83c561..b404503 100644
--- a/src/mesa/state_tracker/st_program.c
+++ b/src/mesa/state_tracker/st_program.c
@@ -244,6 +244,14 @@ st_prepare_vertex_program(struct gl_context *ctx,
stvp->output_semantic_name[slot] = TGSI_SEMANTIC_PSIZE;
stvp->output_semantic_index[slot] = 0;
break;
+ case VERT_RESULT_CLIP_DIST0:
+ stvp->output_semantic_name[slot] = TGSI_SEMANTIC_CLIPDIST;
+ stvp->output_semantic_index[slot] = 0;
+ break;
+ case VERT_RESULT_CLIP_DIST1:
+ stvp->output_semantic_name[slot] = TGSI_SEMANTIC_CLIPDIST;
+ stvp->output_semantic_index[slot] = 1;
+ break;
case VERT_RESULT_EDGE:
assert(0);
break;
@@ -547,6 +555,16 @@ st_translate_fragment_program(struct st_context *st,
input_semantic_index[slot] = 0;
interpMode[slot] = TGSI_INTERPOLATE_CONSTANT;
break;
+ case FRAG_ATTRIB_CLIP_DIST0:
+ input_semantic_name[slot] = TGSI_SEMANTIC_CLIPDIST;
+ input_semantic_index[slot] = 0;
+ interpMode[slot] = TGSI_INTERPOLATE_LINEAR;
+ break;
+ case FRAG_ATTRIB_CLIP_DIST1:
+ input_semantic_name[slot] = TGSI_SEMANTIC_CLIPDIST;
+ input_semantic_index[slot] = 1;
+ interpMode[slot] = TGSI_INTERPOLATE_LINEAR;
+ break;
/* In most cases, there is nothing special about these
* inputs, so adopt a convention to use the generic
* semantic name and the mesa FRAG_ATTRIB_ number as the
--
1.7.1
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