}
-void
-vec4_vs_visitor::emit_clip_distances(dst_reg reg, int offset)
-{
- /* From the GLSL 1.30 spec, section 7.1 (Vertex Shader Special Variables):
- *
- * "If a linked set of shaders forming the vertex stage contains no
- * static write to gl_ClipVertex or gl_ClipDistance, but the
- * application has requested clipping against user clip planes through
- * the API, then the coordinate written to gl_Position is used for
- * comparison against the user clip planes."
- *
- * This function is only called if the shader didn't write to
- * gl_ClipDistance. Accordingly, we use gl_ClipVertex to perform clipping
- * if the user wrote to it; otherwise we use gl_Position.
- */
- gl_varying_slot clip_vertex = VARYING_SLOT_CLIP_VERTEX;
- if (!(prog_data->vue_map.slots_valid & VARYING_BIT_CLIP_VERTEX)) {
- clip_vertex = VARYING_SLOT_POS;
- }
-
- for (int i = 0; i + offset < key->nr_userclip_plane_consts && i < 4;
- ++i) {
- reg.writemask = 1 << i;
- emit(DP4(reg,
- src_reg(output_reg[clip_vertex][0]),
- src_reg(this->userplane[i + offset])));
- }
-}
-
-
-void
-vec4_vs_visitor::setup_uniform_clipplane_values()
-{
- if (key->nr_userclip_plane_consts == 0)
- return;
-
- assert(stage_prog_data->nr_params == (unsigned)this->uniforms * 4);
- brw_stage_prog_data_add_params(stage_prog_data,
- key->nr_userclip_plane_consts * 4);
-
- for (int i = 0; i < key->nr_userclip_plane_consts; ++i) {
- this->userplane[i] = dst_reg(UNIFORM, this->uniforms);
- this->userplane[i].type = BRW_REGISTER_TYPE_F;
- for (int j = 0; j < 4; ++j) {
- stage_prog_data->param[this->uniforms * 4 + j] =
- BRW_PARAM_BUILTIN_CLIP_PLANE(i, j);
- }
- ++this->uniforms;
- }
-}
-
-
void
vec4_vs_visitor::emit_thread_end()
{
- setup_uniform_clipplane_values();
-
- /* Lower legacy ff and ClipVertex clipping to clip distances */
- if (key->nr_userclip_plane_consts > 0) {
- current_annotation = "user clip distances";
-
- output_reg[VARYING_SLOT_CLIP_DIST0][0] =
- dst_reg(this, glsl_type::vec4_type);
- output_reg[VARYING_SLOT_CLIP_DIST1][0] =
- dst_reg(this, glsl_type::vec4_type);
- output_num_components[VARYING_SLOT_CLIP_DIST0][0] = 4;
- output_num_components[VARYING_SLOT_CLIP_DIST1][0] = 4;
-
- emit_clip_distances(output_reg[VARYING_SLOT_CLIP_DIST0][0], 0);
- emit_clip_distances(output_reg[VARYING_SLOT_CLIP_DIST1][0], 4);
- }
-
/* For VS, we always end the thread by emitting a single vertex.
* emit_urb_write_opcode() will take care of setting the eot flag on the
* SEND instruction.