texture compression: getting warmer

1 files changed, 34 insertions, 0 deletions

diff --git a/src/mesa/main/texstore.c b/src/mesa/main/texstore.c
index 3dae1929c4..ea7d7cebb1 100644
--- a/src/mesa/main/texstore.c
+++ b/src/mesa/main/texstore.c
@@ -3280,3 +3280,37 @@ do {									\
       _mesa_problem(NULL,"unexpected bytes/pixel in _mesa_rescale_teximage2d");
    }
 }
+
+
+/**
+ * Upscale an image by replication, not (typical) stretching.
+ * We use this when the image width or height is less than a
+ * certain size (4, 8) and we need to upscale an image.
+ */
+void
+_mesa_upscale_teximage2d (GLsizei inWidth, GLsizei inHeight,
+                          GLsizei outWidth, GLsizei outHeight,
+                          GLint comps, const GLchan *src, GLint srcRowStride,
+                          GLchan *dest )
+{
+   GLint i, j, k;
+
+   ASSERT(outWidth >= inWidth);
+   ASSERT(outHeight >= inHeight);
+   ASSERT(inWidth == 1 || inWidth == 2 || inHeight == 1 || inHeight == 2);
+#if 0
+   ASSERT((outWidth & 3) == 0);
+   ASSERT((outHeight & 3) == 0);
+#endif
+
+   for (i = 0; i < outHeight; i++) {
+      const GLint ii = i % inHeight;
+      for (j = 0; j < outWidth; j++) {
+         const GLint jj = j % inWidth;
+         for (k = 0; k < comps; k++) {
+            dest[(i * outWidth + j) * comps + k]
+               = src[ii * srcRowStride + jj * comps + k];
+         }
+      }
+   }
+}