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authorBrian Paul <brian.paul@tungstengraphics.com>2004-05-02 14:30:46 +0000
committerBrian Paul <brian.paul@tungstengraphics.com>2004-05-02 14:30:46 +0000
commit80fc5ea53e0f1dac9df529965687c159acae057f (patch)
tree7dd652f29e141ae69871d413fa398081a03837da /src/mesa/main
parent883e7a5906b3e287520c1e52bdb76c47ba9bb4a5 (diff)
restored _mesa_rescale_teximage2d()
Diffstat (limited to 'src/mesa/main')
-rw-r--r--src/mesa/main/texstore.c71
-rw-r--r--src/mesa/main/texstore.h7
2 files changed, 78 insertions, 0 deletions
diff --git a/src/mesa/main/texstore.c b/src/mesa/main/texstore.c
index d0529b13c3..3dae1929c4 100644
--- a/src/mesa/main/texstore.c
+++ b/src/mesa/main/texstore.c
@@ -3209,3 +3209,74 @@ _mesa_generate_mipmap(GLcontext *ctx, GLenum target,
} /* loop over mipmap levels */
}
+
+
+/**
+ * Helper function for drivers which need to rescale texture images to
+ * certain aspect ratios.
+ * Nearest filtering only (for broken hardware that can't support
+ * all aspect ratios). This can be made a lot faster, but I don't
+ * really care enough...
+ */
+void _mesa_rescale_teximage2d( GLuint bytesPerPixel, GLuint dstRowStride,
+ GLint srcWidth, GLint srcHeight,
+ GLint dstWidth, GLint dstHeight,
+ const GLvoid *srcImage, GLvoid *dstImage )
+{
+ GLint row, col;
+
+#define INNER_LOOP( TYPE, HOP, WOP ) \
+ for ( row = 0 ; row < dstHeight ; row++ ) { \
+ GLint srcRow = row HOP hScale; \
+ for ( col = 0 ; col < dstWidth ; col++ ) { \
+ GLint srcCol = col WOP wScale; \
+ dst[col] = src[srcRow * srcWidth + srcCol]; \
+ } \
+ dst = (TYPE *) ((GLubyte *) dst + dstRowStride); \
+ } \
+
+#define RESCALE_IMAGE( TYPE ) \
+do { \
+ const TYPE *src = (const TYPE *)srcImage; \
+ TYPE *dst = (TYPE *)dstImage; \
+ \
+ if ( srcHeight <= dstHeight ) { \
+ const GLint hScale = dstHeight / srcHeight; \
+ if ( srcWidth <= dstWidth ) { \
+ const GLint wScale = dstWidth / srcWidth; \
+ INNER_LOOP( TYPE, /, / ); \
+ } \
+ else { \
+ const GLint wScale = srcWidth / dstWidth; \
+ INNER_LOOP( TYPE, /, * ); \
+ } \
+ } \
+ else { \
+ const GLint hScale = srcHeight / dstHeight; \
+ if ( srcWidth <= dstWidth ) { \
+ const GLint wScale = dstWidth / srcWidth; \
+ INNER_LOOP( TYPE, *, / ); \
+ } \
+ else { \
+ const GLint wScale = srcWidth / dstWidth; \
+ INNER_LOOP( TYPE, *, * ); \
+ } \
+ } \
+} while (0)
+
+ switch ( bytesPerPixel ) {
+ case 4:
+ RESCALE_IMAGE( GLuint );
+ break;
+
+ case 2:
+ RESCALE_IMAGE( GLushort );
+ break;
+
+ case 1:
+ RESCALE_IMAGE( GLubyte );
+ break;
+ default:
+ _mesa_problem(NULL,"unexpected bytes/pixel in _mesa_rescale_teximage2d");
+ }
+}
diff --git a/src/mesa/main/texstore.h b/src/mesa/main/texstore.h
index 47775a1bb8..d276ff94e4 100644
--- a/src/mesa/main/texstore.h
+++ b/src/mesa/main/texstore.h
@@ -225,4 +225,11 @@ _mesa_generate_mipmap(GLcontext *ctx, GLenum target,
const struct gl_texture_unit *texUnit,
struct gl_texture_object *texObj);
+
+extern void
+_mesa_rescale_teximage2d(GLuint bytesPerPixel, GLuint dstRowStride,
+ GLint srcWidth, GLint srcHeight,
+ GLint dstWidth, GLint dstHeight,
+ const GLvoid *srcImage, GLvoid *dstImage);
+
#endif