KonstantinSeurer
/
mesa
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

gallium: fix potential divide by zero in fog computation 

It's legal for Fog.Start == Fog.End and conformance testing does so.
This commit is contained in:
Brian Paul 2008-04-23 11:37:49 -06:00
parent 5d873c8718
commit ba47aabc98
1 changed files with 5 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
src/mesa/shader/prog_statevars.c
View File

@ -253,7 +253,8 @@ _mesa_fetch_state(GLcontext *ctx, const gl_state_index state[],
value[0] = ctx->Fog.Density; value[0] = ctx->Fog.Density;
value[1] = ctx->Fog.Start; value[1] = ctx->Fog.Start;
value[2] = ctx->Fog.End; value[2] = ctx->Fog.End;
value[3] = 1.0F / (ctx->Fog.End - ctx->Fog.Start); value[3] = (ctx->Fog.End == ctx->Fog.Start)
? 1.0 : 1.0F / (ctx->Fog.End - ctx->Fog.Start);
return; return;
case STATE_CLIPPLANE: case STATE_CLIPPLANE:
{ {
@ -424,8 +425,9 @@ _mesa_fetch_state(GLcontext *ctx, const gl_state_index state[],
* exp: 2^-(density/ln(2) * fogcoord) * exp: 2^-(density/ln(2) * fogcoord)
* exp2: 2^-((density/(ln(2)^2) * fogcoord)^2) * exp2: 2^-((density/(ln(2)^2) * fogcoord)^2)
*/ */
value[0] = -1.0F / (ctx->Fog.End - ctx->Fog.Start); value[0] = (ctx->Fog.End == ctx->Fog.Start)
value[1] = ctx->Fog.End / (ctx->Fog.End - ctx->Fog.Start); ? 1.0 : -1.0F / (ctx->Fog.End - ctx->Fog.Start);
value[1] = ctx->Fog.End * -value[0];
value[2] = ctx->Fog.Density * ONE_DIV_LN2; value[2] = ctx->Fog.Density * ONE_DIV_LN2;
value[3] = ctx->Fog.Density * ONE_DIV_SQRT_LN2; value[3] = ctx->Fog.Density * ONE_DIV_SQRT_LN2;
return; return;