/* Project 'pos' to screen space (or back again), overwrite with results:
*/
static void brw_clip_project_position(struct brw_clip_compile *c, struct brw_reg pos )
{
struct brw_compile *p = &c->func;
/* calc rhw
*/
brw_math_invert(p, get_element(pos, W), get_element(pos, W));
/* value.xyz *= value.rhw
*/
brw_set_access_mode(p, BRW_ALIGN_16);
brw_MUL(p, brw_writemask(pos, WRITEMASK_XYZ), pos, brw_swizzle1(pos, W));
brw_set_access_mode(p, BRW_ALIGN_1);
}
void brw_emit_point_sprite_setup(struct brw_sf_compile *c, bool allocate)
{
struct brw_compile *p = &c->func;
GLuint i;
c->flag_value = 0xff;
c->nr_verts = 1;
if (allocate)
alloc_regs(c);
copy_z_inv_w(c);
for (i = 0; i < c->nr_setup_regs; i++)
{
struct brw_reg a0 = offset(c->vert[0], i);
GLushort pc, pc_persp, pc_linear, pc_coord_replace;
bool last = calculate_masks(c, i, &pc, &pc_persp, &pc_linear);
pc_coord_replace = calculate_point_sprite_mask(c, i);
pc_persp &= ~pc_coord_replace;
if (pc_persp) {
set_predicate_control_flag_value(p, c, pc_persp);
brw_MUL(p, a0, a0, c->inv_w[0]);
}
/* Point sprite coordinate replacement: A texcoord with this
* enabled gets replaced with the value (x, y, 0, 1) where x and
* y vary from 0 to 1 across the horizontal and vertical of the
* point.
*/
if (pc_coord_replace) {
set_predicate_control_flag_value(p, c, pc_coord_replace);
/* Caculate 1.0/PointWidth */
gen4_math(&c->func,
c->tmp,
BRW_MATH_FUNCTION_INV,
0,
c->dx0,
BRW_MATH_DATA_SCALAR,
BRW_MATH_PRECISION_FULL);
brw_set_default_access_mode(p, BRW_ALIGN_16);
/* dA/dx, dA/dy */
brw_MOV(p, c->m1Cx, brw_imm_f(0.0));
brw_MOV(p, c->m2Cy, brw_imm_f(0.0));
brw_MOV(p, brw_writemask(c->m1Cx, WRITEMASK_X), c->tmp);
if (c->key.sprite_origin_lower_left) {
brw_MOV(p, brw_writemask(c->m2Cy, WRITEMASK_Y), negate(c->tmp));
} else {
brw_MOV(p, brw_writemask(c->m2Cy, WRITEMASK_Y), c->tmp);
}
/* attribute constant offset */
brw_MOV(p, c->m3C0, brw_imm_f(0.0));
if (c->key.sprite_origin_lower_left) {
brw_MOV(p, brw_writemask(c->m3C0, WRITEMASK_YW), brw_imm_f(1.0));
} else {
brw_MOV(p, brw_writemask(c->m3C0, WRITEMASK_W), brw_imm_f(1.0));
}
brw_set_default_access_mode(p, BRW_ALIGN_1);
}
if (pc & ~pc_coord_replace) {
set_predicate_control_flag_value(p, c, pc & ~pc_coord_replace);
brw_MOV(p, c->m1Cx, brw_imm_ud(0));
brw_MOV(p, c->m2Cy, brw_imm_ud(0));
brw_MOV(p, c->m3C0, a0); /* constant value */
}
set_predicate_control_flag_value(p, c, pc);
/* Copy m0..m3 to URB. */
brw_urb_WRITE(p,
brw_null_reg(),
0,
brw_vec8_grf(0, 0),
last ? BRW_URB_WRITE_EOT_COMPLETE
: BRW_URB_WRITE_NO_FLAGS,
4, /* msg len */
0, /* response len */
i*4, /* urb destination offset */
BRW_URB_SWIZZLE_TRANSPOSE);
}
brw_set_default_predicate_control(p, BRW_PREDICATE_NONE);
}
/* Interpolate between two vertices and put the result into a0.0.
* Increment a0.0 accordingly.
*
* Beware that dest_ptr can be equal to v0_ptr!
*/
void brw_clip_interp_vertex( struct brw_clip_compile *c,
struct brw_indirect dest_ptr,
struct brw_indirect v0_ptr, /* from */
struct brw_indirect v1_ptr, /* to */
struct brw_reg t0,
bool force_edgeflag)
{
struct brw_codegen *p = &c->func;
struct brw_reg t_nopersp, v0_ndc_copy;
GLuint slot;
/* Just copy the vertex header:
*/
/*
* After CLIP stage, only first 256 bits of the VUE are read
* back on Ironlake, so needn't change it
*/
brw_copy_indirect_to_indirect(p, dest_ptr, v0_ptr, 1);
/* First handle the 3D and NDC interpolation, in case we
* need noperspective interpolation. Doing it early has no
* performance impact in any case.
*/
/* Take a copy of the v0 NDC coordinates, in case dest == v0. */
if (c->has_noperspective_shading) {
GLuint offset = brw_varying_to_offset(&c->vue_map,
BRW_VARYING_SLOT_NDC);
v0_ndc_copy = get_tmp(c);
brw_MOV(p, v0_ndc_copy, deref_4f(v0_ptr, offset));
}
/* Compute the new 3D position
*
* dest_hpos = v0_hpos * (1 - t0) + v1_hpos * t0
*/
{
GLuint delta = brw_varying_to_offset(&c->vue_map, VARYING_SLOT_POS);
struct brw_reg tmp = get_tmp(c);
brw_MUL(p, vec4(brw_null_reg()), deref_4f(v1_ptr, delta), t0);
brw_MAC(p, tmp, negate(deref_4f(v0_ptr, delta)), t0);
brw_ADD(p, deref_4f(dest_ptr, delta), deref_4f(v0_ptr, delta), tmp);
release_tmp(c, tmp);
}
/* Recreate the projected (NDC) coordinate in the new vertex header */
brw_clip_project_vertex(c, dest_ptr);
/* If we have noperspective attributes,
* we need to compute the screen-space t
*/
if (c->has_noperspective_shading) {
GLuint delta = brw_varying_to_offset(&c->vue_map,
BRW_VARYING_SLOT_NDC);
struct brw_reg tmp = get_tmp(c);
t_nopersp = get_tmp(c);
/* t_nopersp = vec4(v1.xy, dest.xy) */
brw_MOV(p, t_nopersp, deref_4f(v1_ptr, delta));
brw_MOV(p, tmp, deref_4f(dest_ptr, delta));
brw_set_default_access_mode(p, BRW_ALIGN_16);
brw_MOV(p,
brw_writemask(t_nopersp, WRITEMASK_ZW),
brw_swizzle(tmp, 0, 1, 0, 1));
/* t_nopersp = vec4(v1.xy, dest.xy) - v0.xyxy */
brw_ADD(p, t_nopersp, t_nopersp,
negate(brw_swizzle(v0_ndc_copy, 0, 1, 0, 1)));
/* Add the absolute values of the X and Y deltas so that if
* the points aren't in the same place on the screen we get
* nonzero values to divide.
*
* After that, we have vert1 - vert0 in t_nopersp.x and
* vertnew - vert0 in t_nopersp.y
*
* t_nopersp = vec2(|v1.x -v0.x| + |v1.y -v0.y|,
* |dest.x-v0.x| + |dest.y-v0.y|)
*/
brw_ADD(p,
brw_writemask(t_nopersp, WRITEMASK_XY),
brw_abs(brw_swizzle(t_nopersp, 0, 2, 0, 0)),
brw_abs(brw_swizzle(t_nopersp, 1, 3, 0, 0)));
brw_set_default_access_mode(p, BRW_ALIGN_1);
/* If the points are in the same place, just substitute a
* value to avoid divide-by-zero
*/
brw_CMP(p, vec1(brw_null_reg()), BRW_CONDITIONAL_EQ,
vec1(t_nopersp),
brw_imm_f(0));
brw_IF(p, BRW_EXECUTE_1);
brw_MOV(p, t_nopersp, brw_imm_vf4(brw_float_to_vf(1.0),
brw_float_to_vf(0.0),
brw_float_to_vf(0.0),
brw_float_to_vf(0.0)));
brw_ENDIF(p);
/* Now compute t_nopersp = t_nopersp.y/t_nopersp.x and broadcast it. */
brw_math_invert(p, get_element(t_nopersp, 0), get_element(t_nopersp, 0));
brw_MUL(p, vec1(t_nopersp), vec1(t_nopersp),
vec1(suboffset(t_nopersp, 1)));
brw_set_default_access_mode(p, BRW_ALIGN_16);
brw_MOV(p, t_nopersp, brw_swizzle(t_nopersp, 0, 0, 0, 0));
brw_set_default_access_mode(p, BRW_ALIGN_1);
release_tmp(c, tmp);
release_tmp(c, v0_ndc_copy);
}
/* Now we can iterate over each attribute
* (could be done in pairs?)
*/
for (slot = 0; slot < c->vue_map.num_slots; slot++) {
int varying = c->vue_map.slot_to_varying[slot];
GLuint delta = brw_vue_slot_to_offset(slot);
/* HPOS, NDC already handled above */
if (varying == VARYING_SLOT_POS || varying == BRW_VARYING_SLOT_NDC)
continue;
if (varying == VARYING_SLOT_EDGE) {
if (force_edgeflag)
brw_MOV(p, deref_4f(dest_ptr, delta), brw_imm_f(1));
else
brw_MOV(p, deref_4f(dest_ptr, delta), deref_4f(v0_ptr, delta));
} else if (varying == VARYING_SLOT_PSIZ) {
/* PSIZ doesn't need interpolation because it isn't used by the
* fragment shader.
*/
} else if (varying < VARYING_SLOT_MAX) {
/* This is a true vertex result (and not a special value for the VUE
* header), so interpolate:
*
* New = attr0 + t*attr1 - t*attr0
*
* Unless the attribute is flat shaded -- in which case just copy
* from one of the sources (doesn't matter which; already copied from pv)
*/
GLuint interp = c->key.interpolation_mode.mode[slot];
if (interp != INTERP_QUALIFIER_FLAT) {
struct brw_reg tmp = get_tmp(c);
struct brw_reg t =
interp == INTERP_QUALIFIER_NOPERSPECTIVE ? t_nopersp : t0;
brw_MUL(p,
vec4(brw_null_reg()),
deref_4f(v1_ptr, delta),
t);
brw_MAC(p,
tmp,
negate(deref_4f(v0_ptr, delta)),
t);
brw_ADD(p,
deref_4f(dest_ptr, delta),
deref_4f(v0_ptr, delta),
tmp);
release_tmp(c, tmp);
}
else {
brw_MOV(p,
deref_4f(dest_ptr, delta),
deref_4f(v0_ptr, delta));
}
}
}
if (c->vue_map.num_slots % 2) {
GLuint delta = brw_vue_slot_to_offset(c->vue_map.num_slots);
brw_MOV(p, deref_4f(dest_ptr, delta), brw_imm_f(0));
}
if (c->has_noperspective_shading)
release_tmp(c, t_nopersp);
}