Found a 10% performance boost by simply reordering data access when filling in polygon data, and by blitting UV and RGB values with a single copy.

draw.h

@@ -112,10 +112,10 @@ static INLINE void draw_quadstrip_lit(const ps1bsp_vertex_t *vertices, const ps1
         gte_rtps();
         gte_stsxy(&poly->x3);
 
-        poly->r0 = poly->g0 = poly->b0 = (uint8_t)v0->light;
-        poly->r1 = poly->g1 = poly->b1 = (uint8_t)v1->light;
-        poly->r2 = poly->g2 = poly->b2 = (uint8_t)v2->light;
-        poly->r3 = poly->g3 = poly->b3 = (uint8_t)v3->light;
+        poly->r0 = poly->g0 = poly->b0 = (uint8_t)v0->r;
+        poly->r1 = poly->g1 = poly->b1 = (uint8_t)v1->r;
+        poly->r2 = poly->g2 = poly->b2 = (uint8_t)v2->r;
+        poly->r3 = poly->g3 = poly->b3 = (uint8_t)v3->r;
 
         addPrim(ot, poly);
         ++polyCount;
@@ -232,25 +232,36 @@ static INLINE void draw_quadstrip_textured(const ps1bsp_vertex_t *vertices, cons
 
         // Draw a gouraud shaded textured quad
         POLY_GT4 *poly = (POLY_GT4*)mem_prim(sizeof(POLY_GT4));
-        setPolyGT4(poly);
-        gte_stsxy3_gt3(poly);
+
+        // Fill out the quad's data fields in struct order, to optimize data access
+        // RGB and UV fields are blitted as a single value, which is faster than copying each value individually
+        // First vertex and texture CLUT
+        *((u_int*)&poly->r0) = *((u_int*)&v0->r);
+        gte_stsxy0(&poly->x0);
+        *((u_short*)&poly->u0) = *((u_short*)&v0->u);
+        poly->clut = quake_clut;
+
+        // Second vertex and texture page
+        *((u_int*)&poly->r1) = *((u_int*)&v1->r);
+        gte_stsxy1(&poly->x1);
+        *((u_short*)&poly->u1) = *((u_short*)&v1->u);
+        poly->tpage = tpage;
+
+        // Third vertex
+        *((u_int*)&poly->r2) = *((u_int*)&v2->r);
+        gte_stsxy2(&poly->x2);
+        *((u_short*)&poly->u2) = *((u_short*)&v2->u);
 
         // Transform the fourth vertex to complete the quad
         gte_ldv0(&vertices[v3->index]);
         gte_rtps();
-        gte_stsxy(&poly->x3);
 
-        // Texture UVs
-        setUV4(poly, v0->u, v0->v, v1->u, v1->v, v2->u, v2->v, v3->u, v3->v);
-        poly->clut = quake_clut;
-        poly->tpage = tpage;
-
-        // Vertex color lighting
-        poly->r0 = poly->g0 = poly->b0 = (uint8_t)v0->light;
-        poly->r1 = poly->g1 = poly->b1 = (uint8_t)v1->light;
-        poly->r2 = poly->g2 = poly->b2 = (uint8_t)v2->light;
-        poly->r3 = poly->g3 = poly->b3 = (uint8_t)v3->light;
+        // Fourth vertex
+        *((u_int*)&poly->r3) = *((u_int*)&v3->r);
+        gte_stsxy(&poly->x3);
+        *((u_short*)&poly->u3) = *((u_short*)&v3->u);
 
+        setPolyGT4(poly);
         addPrim(ot, poly);
         ++polyCount;
     }

ps1bsp.h

@@ -60,8 +60,8 @@ typedef struct
 typedef struct
 {
 	unsigned short index;
-	unsigned short light;	// Can be made into u_char if we need to store more data; currently u_short for 32-bit alignment purposes
-	unsigned short u, v;	// Can be made into u_char if we need to store more data; currently u_short for 32-bit alignment purposes
+	unsigned char u, v;
+	unsigned char r, g, b, pad;
 } ps1bsp_polyvertex_t;
 
 // Faces are broken up into one or more polygons, each of which can be drawn as a quad/triangle strip with a single texture.