1 files changed, 16 insertions, 8 deletions
diff --git a/src/mesa/swrast/s_span.c b/src/mesa/swrast/s_span.c
index 15a783b236..cfff82b051 100644
--- a/src/mesa/swrast/s_span.c
+++ b/src/mesa/swrast/s_span.c
@@ -1377,12 +1377,14 @@ _swrast_write_rgba_span( GLcontext *ctx, SWspan *span)
 
    ASSERT(span->arrayMask & SPAN_RGBA);
 
-   if (!shader) {
-      /* Add base and specular colors */
-      if (ctx->Fog.ColorSumEnabled ||
-          (ctx->Light.Enabled &&
-           ctx->Light.Model.ColorControl == GL_SEPARATE_SPECULAR_COLOR)) {
-         add_specular(ctx, span);
+   if (span->primitive == GL_BITMAP || !swrast->SpecularVertexAdd) {
+      /* Add primary and specular (diffuse + specular) colors */
+      if (!shader) {
+         if (ctx->Fog.ColorSumEnabled ||
+             (ctx->Light.Enabled &&
+              ctx->Light.Model.ColorControl == GL_SEPARATE_SPECULAR_COLOR)) {
+            add_specular(ctx, span);
+         }
       }
    }
 
@@ -1403,11 +1405,17 @@ _swrast_write_rgba_span( GLcontext *ctx, SWspan *span)
    }
 
    /*
-    * Write to renderbuffers
+    * Write to renderbuffers.
+    * Depending on glDrawBuffer() state and the which color outputs are
+    * written by the fragment shader, we may either replicate one color to
+    * all renderbuffers or write a different color to each renderbuffer.
+    * multiFragOutputs=TRUE for the later case.
     */
    {
       const GLuint numBuffers = fb->_NumColorDrawBuffers;
-      const GLboolean multiFragOutputs = numBuffers > 1;
+      const struct gl_fragment_program *fp = ctx->FragmentProgram._Current;
+      const GLboolean multiFragOutputs = 
+         (fp && fp->Base.OutputsWritten >= (1 << FRAG_RESULT_DATA0));
       GLuint buf;
 
       for (buf = 0; buf < numBuffers; buf++) {