gl3: LIGHTMAPS: Add support for LMSHIFT.

Could be extended to support the LMSHIFT BSPX blob. Currently mostly a
cleanup to make DECOUPLEDLM changes more readable.

src/client/refresh/gl1/header/model.h

@@ -28,7 +28,6 @@
 #define REF_MODEL_H
 
 #define	VERTEXSIZE	7
-#define	DEFAULT_LMSHIFT		4
 
 /* in memory representation */
 
@@ -53,7 +52,6 @@ typedef struct msurface_s
 
 	short texturemins[2];
 	short extents[2];
-
 	short lmshift;
 
 	int light_s, light_t;           /* gl lightmap coordinates */

src/client/refresh/gl3/gl3_light.c

@@ -193,13 +193,13 @@ RecursiveLightPoint(mnode_t *node, vec3_t start, vec3_t end)
 			return 0;
 		}
 
-		ds >>= 4;
-		dt >>= 4;
+		ds >>= surf->lmshift;
+		dt >>= surf->lmshift;
 
 		lightmap = surf->samples;
 		VectorCopy(vec3_origin, pointcolor);
 
-		lightmap += 3 * (dt * ((surf->extents[0] >> 4) + 1) + ds);
+		lightmap += 3 * (dt * ((surf->extents[0] >> surf->lmshift) + 1) + ds);
 
 		for (maps = 0; maps < MAX_LIGHTMAPS_PER_SURFACE && surf->styles[maps] != 255;
 			 maps++)
@@ -218,8 +218,8 @@ RecursiveLightPoint(mnode_t *node, vec3_t start, vec3_t end)
 				pointcolor[j] += lightmap[j] * scale * (1.0 / 255);
 			}
 
-			lightmap += 3 * ((surf->extents[0] >> 4) + 1) *
-						((surf->extents[1] >> 4) + 1);
+			lightmap += 3 * ((surf->extents[0] >> surf->lmshift) + 1) *
+						((surf->extents[1] >> surf->lmshift) + 1);
 		}
 
 		return 1;
@@ -300,8 +300,8 @@ GL3_BuildLightMap(msurface_t *surf, int offsetInLMbuf, int stride)
 		ri.Sys_Error(ERR_DROP, "GL3_BuildLightMap called for non-lit surface");
 	}
 
-	smax = (surf->extents[0] >> 4) + 1;
-	tmax = (surf->extents[1] >> 4) + 1;
+	smax = (surf->extents[0] >> surf->lmshift) + 1;
+	tmax = (surf->extents[1] >> surf->lmshift) + 1;
 	size = smax * tmax;
 
 	stride -= (smax << 2);
@@ -333,8 +333,8 @@ GL3_BuildLightMap(msurface_t *surf, int offsetInLMbuf, int stride)
 
 			for (i = 0; i < tmax; i++, dest += stride)
 			{
-				memset(dest, c, 4*smax);
-				dest += 4*smax;
+				memset(dest, c, 4 * smax);
+				dest += 4 * smax;
 			}
 		}
 

src/client/refresh/gl3/gl3_lightmap.c

@@ -182,15 +182,15 @@ GL3_LM_BuildPolygonFromSurface(gl3model_t *currentmodel, msurface_t *fa)
 		/* lightmap texture coordinates */
 		s = DotProduct(vec, fa->texinfo->vecs[0]) + fa->texinfo->vecs[0][3];
 		s -= fa->texturemins[0];
-		s += fa->light_s * 16;
-		s += 8;
-		s /= BLOCK_WIDTH * 16; /* fa->texinfo->texture->width; */
+		s += fa->light_s * (1 << fa->lmshift);
+		s += (1 << fa->lmshift) * 0.5;
+		s /= BLOCK_WIDTH * (1 << fa->lmshift);
 
 		t = DotProduct(vec, fa->texinfo->vecs[1]) + fa->texinfo->vecs[1][3];
 		t -= fa->texturemins[1];
-		t += fa->light_t * 16;
-		t += 8;
-		t /= BLOCK_HEIGHT * 16; /* fa->texinfo->texture->height; */
+		t += fa->light_t * (1 << fa->lmshift);
+		t += (1 << fa->lmshift) * 0.5;
+		t /= BLOCK_HEIGHT * (1 << fa->lmshift);
 
 		vert->lmTexCoord[0] = s;
 		vert->lmTexCoord[1] = t;
@@ -210,8 +210,8 @@ GL3_LM_CreateSurfaceLightmap(msurface_t *surf)
 		return;
 	}
 
-	smax = (surf->extents[0] >> 4) + 1;
-	tmax = (surf->extents[1] >> 4) + 1;
+	smax = (surf->extents[0] >> surf->lmshift) + 1;
+	tmax = (surf->extents[1] >> surf->lmshift) + 1;
 
 	if (!GL3_LM_AllocBlock(smax, tmax, &surf->light_s, &surf->light_t))
 	{

src/client/refresh/gl3/gl3_model.c

@@ -373,6 +373,7 @@ Mod_LoadFaces(gl3model_t *loadmodel, byte *mod_base, lump_t *l)
 		}
 
 		out->texinfo = loadmodel->texinfo + ti;
+		out->lmshift = DEFAULT_LMSHIFT;
 
 		Mod_CalcSurfaceExtents(loadmodel, out);
 

src/client/refresh/gl3/header/model.h

@@ -67,6 +67,7 @@ typedef struct msurface_s
 
 	short texturemins[2];
 	short extents[2];
+	short lmshift;
 
 	int light_s, light_t;           /* gl lightmap coordinates */
 	int dlight_s, dlight_t;         /* gl lightmap coordinates for dynamic lightmaps */

src/client/refresh/ref_shared.h

@@ -75,6 +75,8 @@ typedef enum
 
 #define MAX_LBM_HEIGHT 480
 #define DEFAULT_NOLERP_LIST "pics/conchars.* pics/ch1.* pics/ch2. pics/ch3.*"
+#define DEFAULT_LMSHIFT 4
+
 extern void R_Printf(int level, const char* msg, ...) PRINTF_ATTR(2, 3);
 
 /* Shared images load */

src/client/refresh/vk/header/model.h

@@ -49,7 +49,6 @@ BRUSH MODELS
 //
 
 #define	VERTEXSIZE	7
-#define	DEFAULT_LMSHIFT		4
 
 typedef struct vkpoly_s
 {