+/**
+ * In the case of colormaterial, the effected material attributes
+ * should already have been bound to point to the incoming color data,
+ * prior to running the pipeline.
+ * This function copies the vertex's color to the material attributes
+ * which are tracking glColor.
+ * It's called per-vertex in the lighting loop.
+ */
+static void
+update_materials(struct gl_context *ctx, struct light_stage_data *store)
+{
+ GLuint i;
+
+ for (i = 0 ; i < store->mat_count ; i++) {
+ /* update the material */
+ COPY_CLEAN_4V(store->mat[i].current, store->mat[i].size, store->mat[i].ptr);
+ /* increment src vertex color pointer */
+ STRIDE_F(store->mat[i].ptr, store->mat[i].stride);
+ }
+
+ /* recompute derived light/material values */
+ _mesa_update_material( ctx, store->mat_bitmask );
+ /* XXX we should only call this if we're tracking/changing the specular
+ * exponent.
+ */
+ _tnl_validate_shine_tables( ctx );
+}
+
+
+/**
+ * Prepare things prior to running the lighting stage.
+ * Return number of material attributes which will track vertex color.
+ */
+static GLuint
+prepare_materials(struct gl_context *ctx,
+ struct vertex_buffer *VB, struct light_stage_data *store)
+{
+ GLuint i;
+
+ store->mat_count = 0;
+ store->mat_bitmask = 0;
+
+ /* Examine the _ColorMaterialBitmask to determine which materials
+ * track vertex color. Override the material attribute's pointer
+ * with the color pointer for each one.
+ */
+ if (ctx->Light.ColorMaterialEnabled) {
+ const GLuint bitmask = ctx->Light._ColorMaterialBitmask;
+ for (i = 0 ; i < MAT_ATTRIB_MAX ; i++)
+ if (bitmask & (1<<i))
+ VB->AttribPtr[_TNL_ATTRIB_MAT_FRONT_AMBIENT + i] = VB->AttribPtr[_TNL_ATTRIB_COLOR0];
+ }
+
+ /* Now, for each material attribute that's tracking vertex color, save
+ * some values (ptr, stride, size, current) that we'll need in
+ * update_materials(), above, that'll actually copy the vertex color to
+ * the material attribute(s).
+ */
+ for (i = _TNL_FIRST_MAT; i <= _TNL_LAST_MAT; i++) {
+ if (VB->AttribPtr[i]->stride) {
+ const GLuint j = store->mat_count++;
+ const GLuint attr = i - _TNL_ATTRIB_MAT_FRONT_AMBIENT;
+ store->mat[j].ptr = VB->AttribPtr[i]->start;
+ store->mat[j].stride = VB->AttribPtr[i]->stride;
+ store->mat[j].size = VB->AttribPtr[i]->size;
+ store->mat[j].current = ctx->Light.Material.Attrib[attr];
+ store->mat_bitmask |= (1<<attr);
+ }
+ }
+
+ /* FIXME: Is this already done?
+ */
+ _mesa_update_material( ctx, ~0 );
+
+ _tnl_validate_shine_tables( ctx );
+
+ return store->mat_count;
+}
+
+/*
+ * Compute dp ^ SpecularExponent.
+ * Lerp between adjacent values in the f(x) lookup table, giving a
+ * continuous function, with adequate overall accuracy. (Though still
+ * pretty good compared to a straight lookup).
+ */
+static inline GLfloat
+lookup_shininess(const struct gl_context *ctx, GLuint face, GLfloat dp)