Back-port OSMesaColorClamp() function/feature from trunk. See bug 4917.

11 files changed, 61 insertions, 16 deletions

diff --git a/Makefile b/Makefile
index ea8d6fb98f5..ce8455b62ad 100644
--- a/Makefile
+++ b/Makefile
@@ -377,7 +377,7 @@ tarballs: rm_depend lib_gz demo_gz glut_gz lib_bz2 demo_bz2 glut_bz2 lib_zip dem
 
 
 rm_depend:
-	@for dep in $(DEPEND_FILES) ; do \
+	for dep in $(DEPEND_FILES) ; do \
 		rm -f $$dep ; \
 		touch $$dep ; \
 	done
diff --git a/docs/VERSIONS b/docs/VERSIONS
index 52d394bd4fa..017d958d5f4 100644
--- a/docs/VERSIONS
+++ b/docs/VERSIONS
@@ -1421,3 +1421,10 @@ Mesa Version History
 	- fixed occasional triangle color interpolation problem on VMS
 	- work around invalid free() call (bug 5131)
 	- fixed BSD X server compilation problem by including stdint.h
+
+
+6.4.2
+    New:
+	- added OSMesaColorClamp() function/feature
+    Bug fixes:
+	- fixed some problems when building on Windows
diff --git a/include/GL/osmesa.h b/include/GL/osmesa.h
index ef645905c4d..8d559783ff5 100644
--- a/include/GL/osmesa.h
+++ b/include/GL/osmesa.h
@@ -61,8 +61,8 @@ extern "C" {
 
 
 #define OSMESA_MAJOR_VERSION 6
-#define OSMESA_MINOR_VERSION 3
-#define OSMESA_PATCH_VERSION 0
+#define OSMESA_MINOR_VERSION 4
+#define OSMESA_PATCH_VERSION 2
 
 
 
@@ -267,6 +267,15 @@ GLAPI OSMESAproc GLAPIENTRY
 OSMesaGetProcAddress( const char *funcName );
 
 
+
+/**
+ * Enable/disable color clamping, off by default.
+ * New in Mesa 6.4.2
+ */
+GLAPI void GLAPIENTRY
+OSMesaColorClamp(GLboolean enable);
+
+
 #if defined(__BEOS__) || defined(__QUICKDRAW__)
 #pragma export off
 #endif
diff --git a/src/mesa/drivers/osmesa/osmesa.c b/src/mesa/drivers/osmesa/osmesa.c
index b2b3539ca3c..36823c70680 100644
--- a/src/mesa/drivers/osmesa/osmesa.c
+++ b/src/mesa/drivers/osmesa/osmesa.c
@@ -1333,3 +1333,17 @@ OSMesaGetProcAddress( const char *funcName )
    }
    return _glapi_get_proc_address(funcName);
 }
+
+
+GLAPI void GLAPIENTRY
+OSMesaColorClamp(GLboolean enable)
+{
+   OSMesaContext osmesa = OSMesaGetCurrentContext();
+
+   if (enable == GL_TRUE) {
+      osmesa->mesa.Color.ClampFragmentColor = GL_TRUE;
+   }
+   else {
+      osmesa->mesa.Color.ClampFragmentColor = GL_FIXED_ONLY_ARB;
+   }
+}
diff --git a/src/mesa/main/blend.c b/src/mesa/main/blend.c
index 61b2b17c0c3..aebc70421ab 100644
--- a/src/mesa/main/blend.c
+++ b/src/mesa/main/blend.c
@@ -574,6 +574,9 @@ void _mesa_init_color( GLcontext * ctx )
    else {
       ctx->Color.DrawBuffer[0] = GL_FRONT;
    }
+
+   ctx->Color.ClampFragmentColor = GL_FIXED_ONLY_ARB;
+   ctx->Color.ClampReadColor = GL_FIXED_ONLY_ARB;
 }
 
 /*@}*/
diff --git a/src/mesa/main/context.c b/src/mesa/main/context.c
index 25a3f6a37d4..11f50b42ce4 100644
--- a/src/mesa/main/context.c
+++ b/src/mesa/main/context.c
@@ -1072,12 +1072,6 @@ init_attrib_groups( GLcontext *ctx )
    ctx->NewState = _NEW_ALL;
    ctx->ErrorValue = (GLenum) GL_NO_ERROR;
    ctx->_Facing = 0;
-#if CHAN_TYPE == GL_FLOAT
-   ctx->ClampFragmentColors = GL_FALSE; /* XXX temporary */
-#else
-   ctx->ClampFragmentColors = GL_TRUE;
-#endif
-   ctx->ClampVertexColors = GL_TRUE;
 
    return GL_TRUE;
 }
diff --git a/src/mesa/main/image.c b/src/mesa/main/image.c
index bd0c5ba1f85..e7b9fbbfb69 100644
--- a/src/mesa/main/image.c
+++ b/src/mesa/main/image.c
@@ -1070,7 +1070,7 @@ _mesa_pack_rgba_span_float( GLcontext *ctx,
 
    if (dstFormat == GL_LUMINANCE || dstFormat == GL_LUMINANCE_ALPHA) {
       /* compute luminance values */
-      if (ctx->ClampFragmentColors) {
+      if (ctx->Color.ClampReadColor == GL_TRUE) {
          for (i = 0; i < n; i++) {
             GLfloat sum = rgba[i][RCOMP] + rgba[i][GCOMP] + rgba[i][BCOMP];
             luminance[i] = CLAMP(sum, 0.0F, 1.0F);
diff --git a/src/mesa/main/mtypes.h b/src/mesa/main/mtypes.h
index 2a0bbd94211..fbf18e0a705 100644
--- a/src/mesa/main/mtypes.h
+++ b/src/mesa/main/mtypes.h
@@ -539,6 +539,9 @@ struct gl_colorbuffer_attrib
    /*@}*/
 
    GLboolean DitherFlag;		/**< Dither enable flag */
+
+   GLenum ClampFragmentColor; /**< GL_TRUE, GL_FALSE or GL_FIXED_ONLY_ARB */
+   GLenum ClampReadColor;     /**< GL_TRUE, GL_FALSE or GL_FIXED_ONLY_ARB */
 };
 
 
@@ -2846,12 +2849,6 @@ struct __GLcontextRec
 		    * We don't have a better way to communicate this value from
 		    * swrast_setup to swrast. */
 
-   /** \name Color clamping (tentative part of GL_ARB_color_clamp_control) */
-   /*@{*/
-   GLboolean ClampFragmentColors;
-   GLboolean ClampVertexColors;
-   /*@}*/
-
    /** \name For debugging/development only */
    /*@{*/
    GLboolean FirstTimeCurrent;
diff --git a/src/mesa/swrast/s_context.c b/src/mesa/swrast/s_context.c
index a127038454d..9ace5bb4c7b 100644
--- a/src/mesa/swrast/s_context.c
+++ b/src/mesa/swrast/s_context.c
@@ -108,6 +108,12 @@ _swrast_update_rasterflags( GLcontext *ctx )
       rasterMask |= ATIFRAGSHADER_BIT;
    }
 
+#if CHAN_TYPE == GL_FLOAT
+   if (ctx->Color.ClampFragmentColor == GL_TRUE) {
+      rasterMask |= CLAMPING_BIT;
+   }
+#endif
+
    SWRAST_CONTEXT(ctx)->_RasterMask = rasterMask;
 }
 
diff --git a/src/mesa/swrast/s_context.h b/src/mesa/swrast/s_context.h
index 5f5efdc22ae..e3b8cbd2619 100644
--- a/src/mesa/swrast/s_context.h
+++ b/src/mesa/swrast/s_context.h
@@ -246,6 +246,7 @@ typedef void (*swrast_tri_func)( GLcontext *ctx, const SWvertex *,
 #define TEXTURE_BIT		0x1000	/**< Texturing really enabled */
 #define FRAGPROG_BIT            0x2000  /**< Fragment program enabled */
 #define ATIFRAGSHADER_BIT       0x4000  /**< ATI Fragment shader enabled */
+#define CLAMPING_BIT            0x8000  /**< Clamp colors to [0,1] */
 /*@}*/
 
 #define _SWRAST_NEW_RASTERMASK (_NEW_BUFFERS|	\
diff --git a/src/mesa/swrast/s_span.c b/src/mesa/swrast/s_span.c
index cf9c1a737b1..fa3a46a849f 100644
--- a/src/mesa/swrast/s_span.c
+++ b/src/mesa/swrast/s_span.c
@@ -1306,6 +1306,20 @@ _swrast_write_rgba_span( GLcontext *ctx, struct sw_span *span)
       }
    }
 
+   /* Clamp color/alpha values over the range [0.0, 1.0] before storage */
+#if CHAN_TYPE == GL_FLOAT
+   if (ctx->Color.ClampFragmentColor) {
+      GLchan (*rgba)[4] = span->array->rgba;
+      GLuint i;
+      for (i = 0; i < span->end; i++) {
+         rgba[i][RCOMP] = CLAMP(rgba[i][RCOMP], 0.0, CHAN_MAXF);
+         rgba[i][GCOMP] = CLAMP(rgba[i][GCOMP], 0.0, CHAN_MAXF);
+         rgba[i][BCOMP] = CLAMP(rgba[i][BCOMP], 0.0, CHAN_MAXF);
+         rgba[i][ACOMP] = CLAMP(rgba[i][ACOMP], 0.0, CHAN_MAXF);
+      }
+   }
+#endif
+
    if (swrast->_RasterMask & MULTI_DRAW_BIT) {
       /* need to do blend/logicop separately for each color buffer */
       multi_write_rgba_span(ctx, span);