fix depth texture tex env bug (#719903)

src/mesa/swrast/s_texture.c

@@ -1,5 +1,3 @@
-/* $Id: s_texture.c,v 1.83 2003/03/04 19:17:31 brianp Exp $ */
-
 /*
  * Mesa 3-D graphics library
  * Version:  5.1
@@ -3811,10 +3809,12 @@ texture_apply( const GLcontext *ctx,
 
    format = texUnit->_Current->Image[baseLevel]->Format;
 
-   if (format == GL_COLOR_INDEX || format == GL_DEPTH_COMPONENT
-       || format == GL_YCBCR_MESA) {
+   if (format == GL_COLOR_INDEX || format == GL_YCBCR_MESA) {
       format = GL_RGBA;  /* a bit of a hack */
    }
+   else if (format == GL_DEPTH_COMPONENT) {
+      format = texUnit->_Current->DepthMode;
+   }
 
    switch (texUnit->EnvMode) {
       case GL_REPLACE: