commit a41edc31ce81daf69157a345525933ca6c560004
author Brian Paul <brian.paul@tungstengraphics.com> Wed May 09 20:02:28 2001 +0000
committer Brian Paul <brian.paul@tungstengraphics.com> Wed May 09 20:02:28 2001 +0000
tree fedb95c9a2e9495b4767c6a3c85c41e4c6f6c821
parent 61cb081a357e60e988ecfa2fd945a8d2657c49f0

check for tiny values in dir[] vector in calcposobjs(), prevents FP underflows later

progs/demos/terrain.c

diff --git a/progs/demos/terrain.c b/progs/demos/terrain.c
index 2fe1df3..5b5ad3e 100644
--- a/progs/demos/terrain.c
+++ b/progs/demos/terrain.c
@@ -81,6 +81,13 @@
    dir[2] = cos(alpha * M_PI / 180.0) * sin(beta * M_PI / 180.0);
    dir[1] = cos(beta * M_PI / 180.0);
 
+   if (dir[0] < 1.0e-5 && dir[0] > -1.0e-5)
+      dir[0] = 0;
+   if (dir[1] < 1.0e-5 && dir[1] > -1.0e-5)
+      dir[1] = 0;
+   if (dir[2] < 1.0e-5 && dir[2] > -1.0e-5)
+      dir[2] = 0;
+
    alpha1 = alpha + FOV / 2.0;
    v1[0] = sin(alpha1 * M_PI / 180.0);
    v1[1] = cos(alpha1 * M_PI / 180.0);