diff options
Diffstat (limited to 'src/mesa/state_tracker/st_atom_scissor.c')
-rw-r--r-- | src/mesa/state_tracker/st_atom_scissor.c | 17 |
1 files changed, 11 insertions, 6 deletions
diff --git a/src/mesa/state_tracker/st_atom_scissor.c b/src/mesa/state_tracker/st_atom_scissor.c index 3fd59e1945c..5e0c51cff0a 100644 --- a/src/mesa/state_tracker/st_atom_scissor.c +++ b/src/mesa/state_tracker/st_atom_scissor.c @@ -31,6 +31,7 @@ */ +#include "main/macros.h" #include "st_context.h" #include "pipe/p_context.h" #include "st_atom.h" @@ -52,15 +53,19 @@ update_scissor( struct st_context *st ) scissor.maxy = fb->Height; if (st->ctx->Scissor.Enabled) { - if ((GLuint)st->ctx->Scissor.X > scissor.minx) + /* need to be careful here with xmax or ymax < 0 */ + GLint xmax = MAX2(0, st->ctx->Scissor.X + st->ctx->Scissor.Width); + GLint ymax = MAX2(0, st->ctx->Scissor.Y + st->ctx->Scissor.Height); + + if (st->ctx->Scissor.X > (GLint)scissor.minx) scissor.minx = st->ctx->Scissor.X; - if ((GLuint)st->ctx->Scissor.Y > scissor.miny) + if (st->ctx->Scissor.Y > (GLint)scissor.miny) scissor.miny = st->ctx->Scissor.Y; - if ((GLuint)st->ctx->Scissor.X + st->ctx->Scissor.Width < scissor.maxx) - scissor.maxx = st->ctx->Scissor.X + st->ctx->Scissor.Width; - if ((GLuint)st->ctx->Scissor.Y + st->ctx->Scissor.Height < scissor.maxy) - scissor.maxy = st->ctx->Scissor.Y + st->ctx->Scissor.Height; + if (xmax < (GLint) scissor.maxx) + scissor.maxx = xmax; + if (ymax < (GLint) scissor.maxy) + scissor.maxy = ymax; /* check for null space */ if (scissor.minx >= scissor.maxx || scissor.miny >= scissor.maxy) |