Initial support for floating point and signed texture formats.

New "FetchTexelFuncF()" function returns texels in floating point format.
Only used for depth component images at this time.
Changed original FetchTexelFunc to return GLchan instead of GLvoid, removing
need for a bunch of ugly casts.

1 files changed, 29 insertions, 14 deletions

diff --git a/src/mesa/main/mtypes.h b/src/mesa/main/mtypes.h
index a5f7e366c1..a9c5f2ceca 100644
--- a/src/mesa/main/mtypes.h
+++ b/src/mesa/main/mtypes.h
@@ -7,9 +7,9 @@
 
 /*
  * Mesa 3-D graphics library
- * Version:  5.1
+ * Version:  6.1
  *
- * Copyright (C) 1999-2003  Brian Paul   All Rights Reserved.
+ * Copyright (C) 1999-2004  Brian Paul   All Rights Reserved.
  *
  * Permission is hereby granted, free of charge, to any person obtaining a
  * copy of this software and associated documentation files (the "Software"),
@@ -955,20 +955,31 @@ struct gl_stencil_attrib {
 #define ENABLE_TEXGEN(i) (ENABLE_TEXGEN0 << (i))
 #define ENABLE_TEXMAT(i) (ENABLE_TEXMAT0 << (i))
 
+
 /**
- * Texel fetch function prototype.
+ * Texel fetch function prototype.  We use texel fetch functions to
+ * extract RGBA, color indexes and depth components out of 1D, 2D and 3D
+ * texture images.  These functions help to isolate us from the gritty
+ * details of all the various texture image encodings.
  * 
  * \param texImage texture image.
  * \param col texel column.
  * \param row texel row.
- * \param img texel level.
- * \param texelOut output texel. If \p texImage is color-index, \p texelOut
- * returns <tt>GLchan[1]</tt>.  If \p texImage is depth, \p texelOut returns
- * <tt>GLfloat[1]</tt>.  Otherwise, \p texelOut returns <tt>GLchan[4]</tt>.
+ * \param img texel image level/layer.
+ * \param texelOut output texel (up to 4 GLchans)
+ */
+typedef void (*FetchTexelFuncC)( const struct gl_texture_image *texImage,
+                                 GLint col, GLint row, GLint img,
+                                 GLchan *texelOut );
+
+/**
+ * As above, but returns floats.
+ * Used for depth component images and for upcoming signed/float
+ * texture images.
  */
-typedef void (*FetchTexelFunc)( const struct gl_texture_image *texImage,
-                                GLint col, GLint row, GLint img,
-                                GLvoid *texelOut );
+typedef void (*FetchTexelFuncF)( const struct gl_texture_image *texImage,
+                                 GLint col, GLint row, GLint img,
+                                 GLfloat *texelOut );
 
 /**
  * Texture format record 
@@ -995,9 +1006,12 @@ struct gl_texture_format {
     * \name Texel fetch function pointers
     */
    /*@{*/
-   FetchTexelFunc FetchTexel1D;
-   FetchTexelFunc FetchTexel2D;
-   FetchTexelFunc FetchTexel3D;
+   FetchTexelFuncC FetchTexel1D;
+   FetchTexelFuncC FetchTexel2D;
+   FetchTexelFuncC FetchTexel3D;
+   FetchTexelFuncF FetchTexel1Df;
+   FetchTexelFuncF FetchTexel2Df;
+   FetchTexelFuncF FetchTexel3Df;
    /*@}*/
 };
 
@@ -1033,7 +1047,8 @@ struct gl_texture_image {
 
    const struct gl_texture_format *TexFormat;
 
-   FetchTexelFunc FetchTexel;	/**< Texel fetch function pointer */
+   FetchTexelFuncC FetchTexelc;	/**< GLchan texel fetch function pointer */
+   FetchTexelFuncF FetchTexelf;	/**< Float texel fetch function pointer */
 
    GLboolean IsCompressed;	/**< GL_ARB_texture_compression */
    GLuint CompressedSize;	/**< GL_ARB_texture_compression */