Mesa (master): gallium/util: added util_format_linear()

[Brian Paul]

Module: Mesa
Branch: master
Commit: 11fbdf726da9fbb2864fad68f23ef51634487560
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=11fbdf726da9fbb2864fad68f23ef51634487560

Author: Brian Paul <brianp at vmware.com>
Date:   Fri Jan 21 18:30:46 2011 -0700

gallium/util: added util_format_linear()

---

 src/gallium/auxiliary/util/u_format.h |   42 ++++++++++++++++++++++++++++++++-
 1 files changed, 41 insertions(+), 1 deletions(-)

diff --git a/src/gallium/auxiliary/util/u_format.h b/src/gallium/auxiliary/util/u_format.h
index 03b73c0..7659a80 100644
--- a/src/gallium/auxiliary/util/u_format.h
+++ b/src/gallium/auxiliary/util/u_format.h
@@ -673,7 +673,8 @@ util_format_has_alpha(enum pipe_format format)
 }
 
 /**
- * Return the matching SRGB format, or PIPE_FORMAT_NONE if none.
+ * Given a linear RGB colorspace format, return the corresponding SRGB
+ * format, or PIPE_FORMAT_NONE if none.
  */
 static INLINE enum pipe_format
 util_format_srgb(enum pipe_format format)
@@ -711,6 +712,45 @@ util_format_srgb(enum pipe_format format)
 }
 
 /**
+ * Given an sRGB format, return the corresponding linear colorspace format.
+ * For non sRGB formats, return the format unchanged.
+ */
+static INLINE enum pipe_format
+util_format_linear(enum pipe_format format)
+{
+   switch (format) {
+   case PIPE_FORMAT_L8_SRGB:
+      return PIPE_FORMAT_L8_UNORM;
+   case PIPE_FORMAT_L8A8_SRGB:
+      return PIPE_FORMAT_L8A8_UNORM;
+   case PIPE_FORMAT_R8G8B8_SRGB:
+      return PIPE_FORMAT_R8G8B8_UNORM;
+   case PIPE_FORMAT_A8B8G8R8_SRGB:
+      return PIPE_FORMAT_A8B8G8R8_UNORM;
+   case PIPE_FORMAT_X8B8G8R8_SRGB:
+      return PIPE_FORMAT_X8B8G8R8_UNORM;
+   case PIPE_FORMAT_B8G8R8A8_SRGB:
+      return PIPE_FORMAT_B8G8R8A8_UNORM;
+   case PIPE_FORMAT_B8G8R8X8_SRGB:
+      return PIPE_FORMAT_B8G8R8X8_UNORM;
+   case PIPE_FORMAT_A8R8G8B8_SRGB:
+      return PIPE_FORMAT_A8R8G8B8_UNORM;
+   case PIPE_FORMAT_X8R8G8B8_SRGB:
+      return PIPE_FORMAT_X8R8G8B8_UNORM;
+   case PIPE_FORMAT_DXT1_SRGB:
+      return PIPE_FORMAT_DXT1_RGB;
+   case PIPE_FORMAT_DXT1_SRGBA:
+      return PIPE_FORMAT_DXT1_RGBA;
+   case PIPE_FORMAT_DXT3_SRGBA:
+      return PIPE_FORMAT_DXT3_RGBA;
+   case PIPE_FORMAT_DXT5_SRGBA:
+      return PIPE_FORMAT_DXT5_RGBA;
+   default:
+      return format;
+   }
+}
+
+/**
  * Return the number of components stored.
  * Formats with block size != 1x1 will always have 1 component (the block).
  */