Fix up alias-16 support.

After getting in contact with serplord, I now know that the sw alias
loading was correct. Turns out the gl loaders was mostly correct, just a
mistaken subtract rather than add. And with that, I can implement alias-16
support in glsl. better yet, since all the work is done in the loader, the
renderer doesn't know anything about it :) However, I need to create some
16-bit models for testing.

include/QF/GLSL/qf_alias.h

@@ -31,10 +31,12 @@
 #ifndef __QF_GLSL_qf_alias_h
 #define __QF_GLSL_qf_alias_h
 
+#include "QF/GLSL/types.h"
+
 typedef struct aliasvrt_s {
-	short       st[2];
-	short       normal[3];
-	byte        vertex[3];
+	GLshort     st[2];
+	GLshort     normal[3];
+	GLushort    vertex[3];
 } aliasvrt_t;
 
 void R_InitAlias (void);

libs/models/alias/gl_mesh.c

@@ -518,7 +518,13 @@ Mod_MakeAliasModelDisplayLists (model_t *m, aliashdr_t *hdr, void *_m, int _s, i
 			trivertx_t *pv = poseverts[i];
 			for (j = 0; j < numorder; j++) {
 				trivertx16_t v;
-				VectorMultSub (pv[vertexorder[j] + hdr->mdl.numverts].v,
+				// convert MD16's split coordinates into something a little
+				// saner. The first chunk of vertices is fully compatible with
+				// IDPO alias models (even the scale). The second chunk is the
+				// fractional bits of the vertex, giving 8.8. However, it's
+				// easier for us to multiply everything by 256 and adjust the
+				// model scale appropriately
+				VectorMultAdd (pv[vertexorder[j] + hdr->mdl.numverts].v,
 							   256, pv[vertexorder[j]].v, v.v);
 				v.lightnormalindex =
 					poseverts[i][vertexorder[j]].lightnormalindex;

libs/models/alias/glsl_model_alias.c

@@ -81,6 +81,8 @@ Mod_LoadSkin (byte *skin, int skinsize, int snum, int gnum, qboolean group,
 void
 Mod_FinalizeAliasModel (model_t *m, aliashdr_t *hdr)
 {
+	if (hdr->mdl.ident == HEADER_MDL16)
+		VectorScale (hdr->mdl.scale, 1/256.0, hdr->mdl.scale);
 }
 
 void
@@ -146,7 +148,12 @@ Mod_MakeAliasModelDisplayLists (model_t *m, aliashdr_t *hdr, void *_m, int _s,
 	for (i = 0, pose = 0; i < hdr->numposes; i++, pose += numverts) {
 		for (j = 0; j < hdr->mdl.numverts; j++) {
 			pv = &poseverts[i][j];
-			VectorCopy (pv->v, verts[pose + j].vertex);
+			if (extra) {
+				VectorMultAdd (pv[hdr->numposes].v, 256, pv->v,
+							   verts[pose + j].vertex);
+			} else {
+				VectorCopy (pv->v, verts[pose + j].vertex);
+			}
 			verts[pose + j].st[0] = st[j].s;
 			verts[pose + j].st[1] = st[j].t;
 			VectorScale (vertex_normals[pv->lightnormalindex], 32767,

libs/models/alias/sw_model_alias.c

@@ -78,13 +78,10 @@ process_frame (maliasframedesc_t *frame, int posenum, int extra)
 	frame_verts = Hunk_AllocName (size, loadname);
 	frame->frame = (byte *) frame_verts - (byte *) pheader;
 
-	// I'm really not sure what the format of md16 is, but for now, I'll
-	// assume the sw renderer is correct (I believe that's what serplord
-	// was using when he developed it), which means the low-order 8 bits
-	// (actually, fractional) are completely separate from the high-order
-	// bits (see R_AliasTransformFinalVert16 in sw_ralias.c), but in
-	// adjacant arrays. This means we can get away with just one memcpy
-	// as there are non endian issues.
+	// The low-order 8 bits (actually, fractional) are completely separate
+	// from the high-order bits (see R_AliasTransformFinalVert16 in
+	// sw_ralias.c), but in adjacant arrays. This means we can get away with
+	// just one memcpy as there are non endian issues.
 	memcpy (frame_verts, poseverts[posenum], size);
 }
 

libs/video/renderer/gl/gl_mod_alias.c

@@ -538,6 +538,8 @@ R_DrawAliasModel (entity_t *e)
 	}
 
 	if (paliashdr->mdl.ident == HEADER_MDL16) {
+		// because we multipled by 256 when we loaded the verts, we have to
+		// scale by 1/256 when drawing.
 		VectorScale (paliashdr->mdl.scale, e->scale / 256.0, scale);
 		vo = GL_GetAliasFrameVerts16 (paliashdr, e);
 	} else {

libs/video/renderer/glsl/glsl_alias.c

@@ -165,7 +165,7 @@ set_arrays (const shaderparam_t *vert, const shaderparam_t *norm,
 		    const shaderparam_t *st, aliasvrt_t *pose)
 {
 	byte       *pose_offs = (byte *) pose;
-	qfglVertexAttribPointer (vert->location, 3, GL_UNSIGNED_BYTE,
+	qfglVertexAttribPointer (vert->location, 3, GL_UNSIGNED_SHORT,
 							 0, sizeof (aliasvrt_t),
 							 pose_offs + field_offset (aliasvrt_t, vertex));
 	qfglVertexAttribPointer (norm->location, 3, GL_SHORT,