Fixed Issue 177: Bug in gluBuildMipMaps2D

This appears to be yet another array index out-of-bounds bug in SGI's
original C sources (see Issue 140 for another). To work around it,
clamping on the maximum X coordinate traversed during scaling of
non-power-of-two textures has been added.


git-svn-id: file:///usr/local/projects/SUN/JOGL/git-svn/svn-server-sync/jogl/branches/JSR-231@398 232f8b59-042b-4e1e-8c03-345bb8c30851

1 files changed, 56 insertions, 0 deletions

diff --git a/src/classes/com/sun/opengl/impl/mipmap/ScaleInternal.java b/src/classes/com/sun/opengl/impl/mipmap/ScaleInternal.java
index 7f6dac8a7..e000c2043 100644
--- a/src/classes/com/sun/opengl/impl/mipmap/ScaleInternal.java
+++ b/src/classes/com/sun/opengl/impl/mipmap/ScaleInternal.java
@@ -334,6 +334,13 @@ public class ScaleInternal {
           highx_float -= 1.0f;
           highx_int++;
         }
+
+        // Clamp to make sure we don't run off the right edge
+        if (highx_int > widthin - 1) {
+          int delta = (highx_int - widthin + 1);
+          lowx_int -= delta;
+          highx_int -= delta;
+        }
       }
       lowy_int = highy_int;
       lowy_float = highy_float;
@@ -545,6 +552,13 @@ public class ScaleInternal {
           highx_float -= 1.0f;
           highx_int++;
         }
+
+        // Clamp to make sure we don't run off the right edge
+        if (highx_int > widthin - 1) {
+          int delta = (highx_int - widthin + 1);
+          lowx_int -= delta;
+          highx_int -= delta;
+        }
       }
       lowy_int = highy_int;
       lowy_float = highy_float;
@@ -819,6 +833,13 @@ public class ScaleInternal {
           highx_float -= 1.0f;
           highx_int++;
         }
+
+        // Clamp to make sure we don't run off the right edge
+        if (highx_int > widthin - 1) {
+          int delta = (highx_int - widthin + 1);
+          lowx_int -= delta;
+          highx_int -= delta;
+        }
       }
       lowy_int = highy_int;
       lowy_float = highy_float;
@@ -1109,6 +1130,13 @@ public class ScaleInternal {
           highx_float -= 1.0f;
           highx_int++;
         }
+
+        // Clamp to make sure we don't run off the right edge
+        if (highx_int > widthin - 1) {
+          int delta = (highx_int - widthin + 1);
+          lowx_int -= delta;
+          highx_int -= delta;
+        }
       }
       lowy_int = highy_int;
       lowy_float = highy_float;
@@ -1390,6 +1418,13 @@ public class ScaleInternal {
           highx_float -= 1.0f;
           highx_int++;
         }
+
+        // Clamp to make sure we don't run off the right edge
+        if (highx_int > widthin - 1) {
+          int delta = (highx_int - widthin + 1);
+          lowx_int -= delta;
+          highx_int -= delta;
+        }
       }
       lowy_int = highy_int;
       lowy_float = highy_float;
@@ -1680,6 +1715,13 @@ public class ScaleInternal {
           highx_float -= 1.0f;
           highx_int++;
         }
+
+        // Clamp to make sure we don't run off the right edge
+        if (highx_int > widthin - 1) {
+          int delta = (highx_int - widthin + 1);
+          lowx_int -= delta;
+          highx_int -= delta;
+        }
       }
       lowy_int = highy_int;
       lowy_float = highy_float;
@@ -1970,6 +2012,13 @@ public class ScaleInternal {
           highx_float -= 1.0f;
           highx_int++;
         }
+
+        // Clamp to make sure we don't run off the right edge
+        if (highx_int > widthin - 1) {
+          int delta = (highx_int - widthin + 1);
+          lowx_int -= delta;
+          highx_int -= delta;
+        }
       }
       lowy_int = highy_int;
       lowy_float = highy_float;
@@ -2196,6 +2245,13 @@ public class ScaleInternal {
           highx_float -= 1.0f;
           highx_int++;
         }
+
+        // Clamp to make sure we don't run off the right edge
+        if (highx_int > widthIn - 1) {
+          int delta = (highx_int - widthIn + 1);
+          lowx_int -= delta;
+          highx_int -= delta;
+        }
       }
       lowy_int = highy_int;
       lowy_float = highy_float;