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

[Eric Anholt]

Module: Mesa
Branch: master
Commit: 11a90af1ef6384b3ac7730d16db9a65b4a799466
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=11a90af1ef6384b3ac7730d16db9a65b4a799466

Author: Eric Anholt <eric at anholt.net>
Date:   Thu Nov  3 17:27:23 2011 -0700

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 at whitecape.org>

---

 src/mesa/swrast/s_readpix.c |   19 +++++++++++++------
 1 files changed, 13 insertions(+), 6 deletions(-)

diff --git a/src/mesa/swrast/s_readpix.c b/src/mesa/swrast/s_readpix.c
index 50422db..54f42db 100644
--- 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;
    }