This does the same thing as we do for triangle clipping -- select the
appropriate source (either dot(hpos,fixed plane) or a clipdistance
slot).
Signed-off-by: Chris Forbes <chr...@ijw.co.nz>
---
src/mesa/drivers/dri/i965/brw_clip_line.c | 66 ++++++++++++++++++++++---------
1 file changed, 47 insertions(+), 19 deletions(-)
diff --git a/src/mesa/drivers/dri/i965/brw_clip_line.c
b/src/mesa/drivers/dri/i965/brw_clip_line.c
index 9001d36..8466b1c 100644
--- a/src/mesa/drivers/dri/i965/brw_clip_line.c
+++ b/src/mesa/drivers/dri/i965/brw_clip_line.c
@@ -85,6 +85,10 @@ static void brw_clip_line_alloc_regs( struct
brw_clip_compile *c )
i++;
}
+ c->reg.vertex_src_mask = retype(brw_vec1_grf(i, 0), BRW_REGISTER_TYPE_UD);
+ c->reg.clipdistance_offset = retype(brw_vec1_grf(i, 1),
BRW_REGISTER_TYPE_W);
+ i++;
+
if (brw->gen == 5) {
c->reg.ff_sync = retype(brw_vec1_grf(i, 0), BRW_REGISTER_TYPE_UD);
i++;
@@ -98,7 +102,6 @@ static void brw_clip_line_alloc_regs( struct
brw_clip_compile *c )
}
-
/* Line clipping, more or less following the following algorithm:
*
* for (p=0;p<MAX_PLANES;p++) {
@@ -125,8 +128,6 @@ static void brw_clip_line_alloc_regs( struct
brw_clip_compile *c )
*/
static void clip_and_emit_line( struct brw_clip_compile *c )
{
- /* FIXME: use VARYING_SLOT_CLIP_VERTEX if available for user clip planes. */
-
struct brw_compile *p = &c->func;
struct brw_context *brw = p->brw;
struct brw_indirect vtx0 = brw_indirect(0, 0);
@@ -136,6 +137,9 @@ static void clip_and_emit_line( struct brw_clip_compile *c )
struct brw_indirect plane_ptr = brw_indirect(4, 0);
struct brw_reg v1_null_ud = retype(vec1(brw_null_reg()),
BRW_REGISTER_TYPE_UD);
GLuint hpos_offset = brw_varying_to_offset(&c->vue_map, VARYING_SLOT_POS);
+ GLint clipdist0_offset = c->key.nr_userclip
+ ? brw_varying_to_offset(&c->vue_map, VARYING_SLOT_CLIP_DIST0)
+ : 0;
brw_MOV(p, get_addr_reg(vtx0), brw_address(c->reg.vertex[0]));
brw_MOV(p, get_addr_reg(vtx1), brw_address(c->reg.vertex[1]));
@@ -160,30 +164,52 @@ static void clip_and_emit_line( struct brw_clip_compile
*c )
brw_set_predicate_control(p, BRW_PREDICATE_NONE);
+ /* Set the initial vertex source mask: The first 6 planes are the bounds
+ * of the view volume; the next 8 planes are the user clipping planes.
+ */
+ brw_MOV(p, c->reg.vertex_src_mask, brw_imm_ud(0x3fc0));
+
+ /* Set the initial clipdistance offset to be 6 floats before
gl_ClipDistance[0].
+ * We'll increment 6 times before we start hitting actual user clipping. */
+ brw_MOV(p, c->reg.clipdistance_offset, brw_imm_d(clipdist0_offset -
6*sizeof(float)));
+
brw_DO(p, BRW_EXECUTE_1);
{
/* if (planemask & 1)
*/
brw_set_conditionalmod(p, BRW_CONDITIONAL_NZ);
brw_AND(p, v1_null_ud, c->reg.planemask, brw_imm_ud(1));
-
+
brw_IF(p, BRW_EXECUTE_1);
{
- if (c->key.nr_userclip)
- brw_MOV(p, c->reg.plane_equation, deref_4f(plane_ptr, 0));
- else
- brw_MOV(p, c->reg.plane_equation, deref_4b(plane_ptr, 0));
-
- /* dp = DP4(vtx->position, plane)
- */
- brw_DP4(p, vec4(c->reg.dp0), deref_4f(vtx0, hpos_offset),
c->reg.plane_equation);
-
- /* if (IS_NEGATIVE(dp1))
- */
- brw_set_conditionalmod(p, BRW_CONDITIONAL_L);
- brw_DP4(p, vec4(c->reg.dp1), deref_4f(vtx1, hpos_offset),
c->reg.plane_equation);
- brw_IF(p, BRW_EXECUTE_1);
- {
+ brw_set_conditionalmod(p, BRW_CONDITIONAL_NZ);
+ brw_AND(p, v1_null_ud, c->reg.vertex_src_mask, brw_imm_ud(1));
+ brw_IF(p, BRW_EXECUTE_1);
+ {
+ /* user clip distance: just fetch the correct float from each
vertex */
+ struct brw_indirect temp_ptr = brw_indirect(7, 0);
+ brw_ADD(p, get_addr_reg(temp_ptr), get_addr_reg(vtx0),
c->reg.clipdistance_offset);
+ brw_MOV(p, c->reg.dp0, deref_1f(temp_ptr, 0));
+ brw_ADD(p, get_addr_reg(temp_ptr), get_addr_reg(vtx1),
c->reg.clipdistance_offset);
+ brw_MOV(p, c->reg.dp1, deref_1f(temp_ptr, 0));
+ }
+ brw_ELSE(p);
+ {
+ /* fixed plane: fetch the hpos, dp4 against the plane. */
+ if (c->key.nr_userclip)
+ brw_MOV(p, c->reg.plane_equation, deref_4f(plane_ptr, 0));
+ else
+ brw_MOV(p, c->reg.plane_equation, deref_4b(plane_ptr, 0));
+
+ brw_DP4(p, vec4(c->reg.dp0), deref_4f(vtx0, hpos_offset),
c->reg.plane_equation);
+ brw_DP4(p, vec4(c->reg.dp1), deref_4f(vtx1, hpos_offset),
c->reg.plane_equation);
+ }
+ brw_ENDIF(p);
+
+ brw_CMP(p, brw_null_reg(), BRW_CONDITIONAL_L, vec1(c->reg.dp1),
brw_imm_f(0.0f));
+
+ brw_IF(p, BRW_EXECUTE_1);
+ {
/*
* Both can be negative on GM965/G965 due to RHW workaround
* if so, this object should be rejected.
@@ -244,6 +270,8 @@ static void clip_and_emit_line( struct brw_clip_compile *c )
*/
brw_set_conditionalmod(p, BRW_CONDITIONAL_NZ);
brw_SHR(p, c->reg.planemask, c->reg.planemask, brw_imm_ud(1));
+ brw_SHR(p, c->reg.vertex_src_mask, c->reg.vertex_src_mask,
brw_imm_ud(1));
+ brw_ADD(p, c->reg.clipdistance_offset, c->reg.clipdistance_offset,
brw_imm_w(sizeof(float)));
}
brw_WHILE(p);
--
1.8.3.4
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