swrast: Add support for glReadPixels() to integer types.

With this change, i965 passes
GL_EXT_texture_integer/fbo_integer_precision_clear

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>

diff --git a/src/mesa/swrast/s_readpix.c b/src/mesa/swrast/s_readpix.c
index 50422dbd59f990da90cdf5d171dd26180005bce4..54f42db0254e68ba1e555a21b44320cdbeddda60 100644 (file)
--- a/src/mesa/swrast/s_readpix.c
+++ b/src/mesa/swrast/s_readpix.c
@@ -236,7 +236,10 @@ slow_read_rgba_pixels( struct gl_context *ctx,
                       GLbitfield transferOps )
 {
    struct gl_renderbuffer *rb = ctx->ReadBuffer->_ColorReadBuffer;
-   GLfloat rgba[MAX_WIDTH][4];
+   union {
+      float f[MAX_WIDTH][4];
+      unsigned int i[MAX_WIDTH][4];
+   } rgba;
    GLubyte *dst, *map;
    int dstStride, stride, j;
 
@@ -248,11 +251,15 @@ slow_read_rgba_pixels( struct gl_context *ctx,
                               &map, &stride);
 
    for (j = 0; j < height; j++) {
-      _mesa_unpack_rgba_row(_mesa_get_srgb_format_linear(rb->Format),
-                           width, map, rgba);
-      _mesa_pack_rgba_span_float(ctx, width, rgba, format, type, dst,
-                                packing, transferOps);
-
+      if (_mesa_is_integer_format(format)) {
+        _mesa_unpack_int_rgba_row(rb->Format, width, map, rgba.i);
+        _mesa_pack_rgba_span_int(ctx, width, rgba.i, format, type, dst);
+      } else {
+        _mesa_unpack_rgba_row(_mesa_get_srgb_format_linear(rb->Format),
+                              width, map, rgba.f);
+        _mesa_pack_rgba_span_float(ctx, width, rgba.f, format, type, dst,
+                                   packing, transferOps);
+      }
       dst += dstStride;
       map += stride;
    }