[Mesa-dev] [PATCH] i965: handle gl_PointCoord for Gen4 and Gen5 platform
Yuanhan Liu
yuanhan.liu at linux.intel.com
Fri Feb 17 00:09:37 PST 2012
This patch add the support of gl_PointCoord gl builtin var for platform
gen4 and gen5(ILK).
We can get the point start coord and the current pixel coord, and the
only left element needed is the point size. Thus I wrote another simple
SF routine for that.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=45975
---
I am somehow not quite sure that this is the right way to implement
gl_PointCoord for gen4 and gen5 platform. But it does work on G45 and
ILK(the two platform I've tested, Zhao jian will help to test more
gen4 platforms).
Thus comments are hugely welcome!!!
NOTE: This is a candidate for stable release branches.
Signed-off-by: Yuanhan Liu <yuanhan.liu at linux.intel.com>
---
src/mesa/drivers/dri/i965/brw_fs.cpp | 27 +++++++++++++
src/mesa/drivers/dri/i965/brw_fs.h | 1 +
src/mesa/drivers/dri/i965/brw_fs_visitor.cpp | 2 +
src/mesa/drivers/dri/i965/brw_sf.c | 6 ++-
src/mesa/drivers/dri/i965/brw_sf.h | 2 +
src/mesa/drivers/dri/i965/brw_sf_emit.c | 53 ++++++++++++++++++++++++++
6 files changed, 90 insertions(+), 1 deletions(-)
diff --git a/src/mesa/drivers/dri/i965/brw_fs.cpp b/src/mesa/drivers/dri/i965/brw_fs.cpp
index 6ecaa6c..178b9c9c 100644
--- a/src/mesa/drivers/dri/i965/brw_fs.cpp
+++ b/src/mesa/drivers/dri/i965/brw_fs.cpp
@@ -421,6 +421,33 @@ fs_visitor::emit_fragcoord_interpolation(ir_variable *ir)
}
fs_reg *
+fs_visitor::emit_pointcoord_interpolation_gen4(ir_variable *ir)
+{
+ fs_reg *reg = new(this->mem_ctx) fs_reg(this, ir->type);
+ fs_reg pntcoord = *reg;
+ int urb_start = c->nr_payload_regs + c->prog_data.curb_read_length;
+ fs_reg pnt_size_rcp = fs_reg(brw_vec1_grf(urb_start, 0));
+ bool render_to_fbo = ctx->DrawBuffer->Name != 0;
+
+ /* gl_PointCoord.x */
+ emit(BRW_OPCODE_MUL, pntcoord, this->delta_x[BRW_WM_PERSPECTIVE_PIXEL_BARYCENTRIC], pnt_size_rcp);
+ pntcoord.reg_offset++;
+
+ /* gl_PointCoord.y */
+ emit(BRW_OPCODE_MUL, pntcoord, this->delta_y[BRW_WM_PERSPECTIVE_PIXEL_BARYCENTRIC], pnt_size_rcp);
+ /*
+ * Window coordinates in an FBO are inverted, which means coord in Y
+ * must be inverted, too.
+ */
+ if ((ctx->Point.SpriteOrigin == GL_LOWER_LEFT) != render_to_fbo) {
+ pntcoord.negate = true;
+ emit(BRW_OPCODE_ADD, pntcoord, pntcoord, fs_reg(1.0f));
+ }
+
+ return reg;
+}
+
+fs_reg *
fs_visitor::emit_general_interpolation(ir_variable *ir)
{
fs_reg *reg = new(this->mem_ctx) fs_reg(this, ir->type);
diff --git a/src/mesa/drivers/dri/i965/brw_fs.h b/src/mesa/drivers/dri/i965/brw_fs.h
index 5fdc055..782c695 100644
--- a/src/mesa/drivers/dri/i965/brw_fs.h
+++ b/src/mesa/drivers/dri/i965/brw_fs.h
@@ -517,6 +517,7 @@ public:
void emit_dummy_fs();
fs_reg *emit_fragcoord_interpolation(ir_variable *ir);
fs_reg *emit_frontfacing_interpolation(ir_variable *ir);
+ fs_reg *emit_pointcoord_interpolation_gen4(ir_variable *ir);
fs_reg *emit_general_interpolation(ir_variable *ir);
void emit_interpolation_setup_gen4();
void emit_interpolation_setup_gen6();
diff --git a/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp b/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp
index ea8cd37..ed53ad5 100644
--- a/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp
+++ b/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp
@@ -63,6 +63,8 @@ fs_visitor::visit(ir_variable *ir)
reg = emit_fragcoord_interpolation(ir);
} else if (!strcmp(ir->name, "gl_FrontFacing")) {
reg = emit_frontfacing_interpolation(ir);
+ } else if (!strcmp(ir->name, "gl_PointCoord") && intel->gen < 6) {
+ reg = emit_pointcoord_interpolation_gen4(ir);
} else {
reg = emit_general_interpolation(ir);
}
diff --git a/src/mesa/drivers/dri/i965/brw_sf.c b/src/mesa/drivers/dri/i965/brw_sf.c
index 54c27f9..69c507a 100644
--- a/src/mesa/drivers/dri/i965/brw_sf.c
+++ b/src/mesa/drivers/dri/i965/brw_sf.c
@@ -84,7 +84,9 @@ static void compile_sf_prog( struct brw_context *brw,
break;
case SF_POINTS:
c.nr_verts = 1;
- if (key->do_point_sprite)
+ if (key->do_point_sprite && key->do_point_coord)
+ brw_emit_point_coord_setup( &c, true );
+ else if (key->do_point_sprite)
brw_emit_point_sprite_setup( &c, true );
else
brw_emit_point_setup( &c, true );
@@ -167,6 +169,8 @@ brw_upload_sf_prog(struct brw_context *brw)
key.point_sprite_coord_replace |= (1 << i);
}
}
+ if (brw->fragment_program->Base.InputsRead & BITFIELD64_BIT(FRAG_ATTRIB_PNTC))
+ key.do_point_coord = 1;
key.sprite_origin_lower_left = (ctx->Point.SpriteOrigin == GL_LOWER_LEFT);
/* _NEW_LIGHT */
key.do_flat_shading = (ctx->Light.ShadeModel == GL_FLAT);
diff --git a/src/mesa/drivers/dri/i965/brw_sf.h b/src/mesa/drivers/dri/i965/brw_sf.h
index 4ef0240..d4c70e7 100644
--- a/src/mesa/drivers/dri/i965/brw_sf.h
+++ b/src/mesa/drivers/dri/i965/brw_sf.h
@@ -52,6 +52,7 @@ struct brw_sf_prog_key {
GLuint do_flat_shading:1;
GLuint frontface_ccw:1;
GLuint do_point_sprite:1;
+ GLuint do_point_coord:1;
GLuint sprite_origin_lower_left:1;
GLuint userclip_active:1;
};
@@ -101,6 +102,7 @@ void brw_emit_tri_setup( struct brw_sf_compile *c, bool allocate );
void brw_emit_line_setup( struct brw_sf_compile *c, bool allocate );
void brw_emit_point_setup( struct brw_sf_compile *c, bool allocate );
void brw_emit_point_sprite_setup( struct brw_sf_compile *c, bool allocate );
+void brw_emit_point_coord_setup( struct brw_sf_compile *c, bool allocate );
void brw_emit_anyprim_setup( struct brw_sf_compile *c );
int brw_sf_compute_urb_entry_read_offset(struct intel_context *intel);
diff --git a/src/mesa/drivers/dri/i965/brw_sf_emit.c b/src/mesa/drivers/dri/i965/brw_sf_emit.c
index 1ee0098..b1e03c7 100644
--- a/src/mesa/drivers/dri/i965/brw_sf_emit.c
+++ b/src/mesa/drivers/dri/i965/brw_sf_emit.c
@@ -559,6 +559,59 @@ void brw_emit_line_setup(struct brw_sf_compile *c, bool allocate)
}
}
+/*
+ * A special routine just for handling gl_PointCoord builtin var
+ *
+ * We don't handle the point coord origin here but instead at the
+ * fragment shader code generation time.
+ */
+void brw_emit_point_coord_setup(struct brw_sf_compile *c, bool allocate)
+{
+ struct brw_compile *p = &c->func;
+ GLuint i;
+
+ c->nr_verts = 1;
+
+ if (allocate)
+ alloc_regs(c);
+
+ for (i = 0; i < c->nr_setup_regs; i++) {
+ bool last = (i == c->nr_setup_regs - 1);
+ /* Caculate 1.0/PointWidth */
+ brw_math(&c->func,
+ c->tmp,
+ BRW_MATH_FUNCTION_INV,
+ BRW_MATH_SATURATE_NONE,
+ 0,
+ c->dx0,
+ BRW_MATH_DATA_SCALAR,
+ BRW_MATH_PRECISION_FULL);
+
+ brw_set_access_mode(p, BRW_ALIGN_16);
+ /* dA/dx, dA/dy */
+ brw_MOV(p, brw_writemask(c->m1Cx, WRITEMASK_X), c->tmp);
+ brw_MOV(p, brw_writemask(c->m2Cy, WRITEMASK_Y), c->tmp);
+
+ /* attribute constant offset */
+ brw_MOV(p, brw_writemask(c->m3C0, WRITEMASK_W), brw_imm_f(1.0));
+ brw_set_access_mode(p, BRW_ALIGN_1);
+
+ /* Copy m0..m3 to URB. */
+ brw_urb_WRITE(p,
+ brw_null_reg(),
+ 0,
+ brw_vec8_grf(0, 0),
+ 0, /* allocate */
+ 1, /* used */
+ 4, /* msg len */
+ 0, /* response len */
+ last, /* eot */
+ last, /* writes complete */
+ i*4, /* urb destination offset */
+ BRW_URB_SWIZZLE_TRANSPOSE);
+ }
+}
+
void brw_emit_point_sprite_setup(struct brw_sf_compile *c, bool allocate)
{
struct brw_compile *p = &c->func;
--
1.7.4.4
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