st/mesa: need to translate clear color according to surface's base format

When clearing a GL_LUMINANCE_ALPHA buffer, for example, we need to convert
the clear color (R,G,B,A) to (R,R,R,A).  We were doing this for texture border
colors but not renderbuffers.  Move the translation function to st_format.c
and share it.

This fixes the piglit fbo-clear-formats test.

NOTE: This is a candidate for the 7.9 and 7.10 branches.

1 files changed, 52 insertions, 0 deletions

diff --git a/src/mesa/state_tracker/st_format.c b/src/mesa/state_tracker/st_format.c
index 3f9c322d9a..577ee6189b 100644
--- a/src/mesa/state_tracker/st_format.c
+++ b/src/mesa/state_tracker/st_format.c
@@ -1095,3 +1095,55 @@ st_sampler_compat_formats(enum pipe_format format1, enum pipe_format format2)
 
    return GL_FALSE;
 }
+
+
+
+/**
+ * This is used for translating texture border color and the clear
+ * color.  For example, the clear color is interpreted according to
+ * the renderbuffer's base format.  For example, if clearing a
+ * GL_LUMINANCE buffer, ClearColor[0] = luminance and ClearColor[1] =
+ * alpha.  Similarly for texture border colors.
+ */
+void
+st_translate_color(const GLfloat colorIn[4], GLenum baseFormat,
+                   GLfloat colorOut[4])
+{
+   switch (baseFormat) {
+   case GL_RED:
+      colorOut[0] = colorIn[0];
+      colorOut[1] = 0.0F;
+      colorOut[2] = 0.0F;
+      colorOut[3] = 1.0F;
+      break;
+   case GL_RG:
+      colorOut[0] = colorIn[0];
+      colorOut[1] = colorIn[1];
+      colorOut[2] = 0.0F;
+      colorOut[3] = 1.0F;
+      break;
+   case GL_RGB:
+      colorOut[0] = colorIn[0];
+      colorOut[1] = colorIn[1];
+      colorOut[2] = colorIn[2];
+      colorOut[3] = 1.0F;
+      break;
+   case GL_ALPHA:
+      colorOut[0] = colorOut[1] = colorOut[2] = 0.0;
+      colorOut[3] = colorIn[3];
+      break;
+   case GL_LUMINANCE:
+      colorOut[0] = colorOut[1] = colorOut[2] = colorIn[0];
+      colorOut[3] = 1.0;
+      break;
+   case GL_LUMINANCE_ALPHA:
+      colorOut[0] = colorOut[1] = colorOut[2] = colorIn[0];
+      colorOut[3] = colorIn[3];
+      break;
+   case GL_INTENSITY:
+      colorOut[0] = colorOut[1] = colorOut[2] = colorOut[3] = colorIn[0];
+      break;
+   default:
+      COPY_4V(colorOut, colorIn);
+   }
+}