diff options
| -rw-r--r-- | src/gallium/drivers/llvmpipe/lp_setup_point.c | 71 |
1 files changed, 54 insertions, 17 deletions
diff --git a/src/gallium/drivers/llvmpipe/lp_setup_point.c b/src/gallium/drivers/llvmpipe/lp_setup_point.c index 3b217f95447..c91e85f9159 100644 --- a/src/gallium/drivers/llvmpipe/lp_setup_point.c +++ b/src/gallium/drivers/llvmpipe/lp_setup_point.c @@ -64,12 +64,37 @@ constant_coef(struct lp_setup_context *setup, } +static void +point_persp_coeff(struct lp_setup_context *setup, + struct lp_rast_triangle *point, + const struct point_info *info, + unsigned slot, + unsigned i) +{ + /* + * Fragment shader expects pre-multiplied w for LP_INTERP_PERSPECTIVE. A + * better stratergy would be to take the primitive in consideration when + * generating the fragment shader key, and therefore avoid the per-fragment + * perspective divide. + */ + + float w0 = info->v0[0][3]; + + assert(i < 4); + + point->inputs.a0[slot][i] = info->v0[slot][i]*w0; + point->inputs.dadx[slot][i] = 0.0f; + point->inputs.dady[slot][i] = 0.0f; +} + + /** * Setup automatic texcoord coefficients (for sprite rendering). * \param slot the vertex attribute slot to setup * \param i the attribute channel in [0,3] * \param sprite_coord_origin one of PIPE_SPRITE_COORD_x - * \param perspective_proj will the TEX instruction do a divide by Q? + * \param perspective does the shader expects pre-multiplied w, i.e., + * LP_INTERP_PERSPECTIVE is specified in the shader key */ static void texcoord_coef(struct lp_setup_context *setup, @@ -78,7 +103,7 @@ texcoord_coef(struct lp_setup_context *setup, unsigned slot, unsigned i, unsigned sprite_coord_origin, - boolean perspective_proj) + boolean perspective) { assert(i < 4); @@ -92,7 +117,7 @@ texcoord_coef(struct lp_setup_context *setup, point->inputs.dady[slot][0] = dady; point->inputs.a0[slot][0] = 0.5 - (dadx * x0 + dady * y0); - if (!perspective_proj) { + if (perspective) { /* Divide coefficients by vertex.w here. * * It would be clearer to always multiply by w0 above and @@ -119,7 +144,7 @@ texcoord_coef(struct lp_setup_context *setup, point->inputs.dady[slot][1] = dady; point->inputs.a0[slot][1] = 0.5 - (dadx * x0 + dady * y0); - if (!perspective_proj) { + if (perspective) { float w0 = info->v0[0][3]; point->inputs.dadx[slot][1] *= w0; point->inputs.dady[slot][1] *= w0; @@ -193,11 +218,17 @@ setup_point_coefficients( struct lp_setup_context *setup, /* setup interpolation for all the remaining attributes: */ for (slot = 0; slot < setup->fs.nr_inputs; slot++) { + enum lp_interp interp = setup->fs.input[slot].interp; + boolean perspective = !!(interp == LP_INTERP_PERSPECTIVE); unsigned vert_attr = setup->fs.input[slot].src_index; unsigned usage_mask = setup->fs.input[slot].usage_mask; unsigned i; + + if (perspective & usage_mask) { + fragcoord_usage_mask |= TGSI_WRITEMASK_W; + } - switch (setup->fs.input[slot].interp) { + switch (interp) { case LP_INTERP_POSITION: /* * The generated pixel interpolators will pick up the coeffs from @@ -210,32 +241,38 @@ setup_point_coefficients( struct lp_setup_context *setup, case LP_INTERP_LINEAR: /* Sprite tex coords may use linear interpolation someday */ /* fall-through */ - case LP_INTERP_PERSPECTIVE: /* check if the sprite coord flag is set for this attribute. * If so, set it up so it up so x and y vary from 0 to 1. */ if (shader->info.input_semantic_name[slot] == TGSI_SEMANTIC_GENERIC) { - const int index = shader->info.input_semantic_index[slot]; + unsigned semantic_index = shader->info.input_semantic_index[slot]; /* Note that sprite_coord enable is a bitfield of * PIPE_MAX_SHADER_OUTPUTS bits. */ - if (index < PIPE_MAX_SHADER_OUTPUTS && - (setup->sprite_coord_enable & (1 << index))) { - for (i = 0; i < NUM_CHANNELS; i++) - if (usage_mask & (1 << i)) + if (semantic_index < PIPE_MAX_SHADER_OUTPUTS && + (setup->sprite_coord_enable & (1 << semantic_index))) { + for (i = 0; i < NUM_CHANNELS; i++) { + if (usage_mask & (1 << i)) { texcoord_coef(setup, point, info, slot + 1, i, setup->sprite_coord_origin, - (usage_mask & TGSI_WRITEMASK_W)); - fragcoord_usage_mask |= TGSI_WRITEMASK_W; - break; + perspective); + } + } + break; } } - /* FALLTHROUGH */ + /* fall-through */ case LP_INTERP_CONSTANT: for (i = 0; i < NUM_CHANNELS; i++) { - if (usage_mask & (1 << i)) - constant_coef(setup, point, slot+1, info->v0[vert_attr][i], i); + if (usage_mask & (1 << i)) { + if (perspective) { + point_persp_coeff(setup, point, info, slot+1, i); + } + else { + constant_coef(setup, point, slot+1, info->v0[vert_attr][i], i); + } + } } break; |