diff --git a/src/gallium/drivers/llvmpipe/lp_rast.h b/src/gallium/drivers/llvmpipe/lp_rast.h index 39ff6af327f..c57f2ea11de 100644 --- a/src/gallium/drivers/llvmpipe/lp_rast.h +++ b/src/gallium/drivers/llvmpipe/lp_rast.h @@ -46,20 +46,10 @@ struct lp_scene; struct lp_fence; struct cmd_bin; -#define FIXED_TYPE_WIDTH 32 /** For sub-pixel positioning */ -#define FIXED_ORDER 8 +#define FIXED_ORDER 4 #define FIXED_ONE (1<draw_regions[i]); } } - /* - * Check if subdivision of triangles is needed if the framebuffer - * is larger than our MAX_FIXED_LENGTH can accomodate. + /* If the framebuffer is large we have to think about fixed-point + * integer overflow. For 2K by 2K images, coordinates need 15 bits + * (2^11 + 4 subpixel bits). The product of two such numbers would + * use 30 bits. Any larger and we could overflow a 32-bit int. + * + * To cope with this problem we check if triangles are large and + * subdivide them if needed. */ - setup->subdivide_large_triangles = (setup->fb.width > MAX_FIXED_LENGTH && - setup->fb.height > MAX_FIXED_LENGTH); + setup->subdivide_large_triangles = (setup->fb.width > 2048 && + setup->fb.height > 2048); } setup->dirty = 0; diff --git a/src/gallium/drivers/llvmpipe/lp_setup_tri.c b/src/gallium/drivers/llvmpipe/lp_setup_tri.c index cf67f29f0e3..da9967ad3f1 100644 --- a/src/gallium/drivers/llvmpipe/lp_setup_tri.c +++ b/src/gallium/drivers/llvmpipe/lp_setup_tri.c @@ -995,7 +995,7 @@ check_subdivide_triangle(struct lp_setup_context *setup, const float (*v2)[4], triangle_func_t tri) { - const float maxLen = MAX_FIXED_LENGTH; /* longest permissible edge, in pixels */ + const float maxLen = 2048.0f; /* longest permissible edge, in pixels */ float dx10, dy10, len10; float dx21, dy21, len21; float dx02, dy02, len02;