diff options
Diffstat (limited to 'src/gallium/drivers/llvmpipe/lp_setup.c')
| -rw-r--r-- | src/gallium/drivers/llvmpipe/lp_setup.c | 14 |
1 files changed, 9 insertions, 5 deletions
diff --git a/src/gallium/drivers/llvmpipe/lp_setup.c b/src/gallium/drivers/llvmpipe/lp_setup.c index d686500135d..5fde01fa13b 100644 --- a/src/gallium/drivers/llvmpipe/lp_setup.c +++ b/src/gallium/drivers/llvmpipe/lp_setup.c @@ -1007,12 +1007,16 @@ try_update_scene_state( struct lp_setup_context *setup ) &setup->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; |