+ // nudge it toward the view to make sure it isn't in a wall
+ Matrix4x4_ToVectors(&ent->matrix, mforward, mleft, mup, org);
+ VectorSubtract(org, r_view.forward, org);
+ switch(model->sprite.sprnum_type)
+ {
+ case SPR_VP_PARALLEL_UPRIGHT:
+ // flames and such
+ // vertical beam sprite, faces view plane
+ scale = ent->scale / sqrt(r_view.forward[0]*r_view.forward[0]+r_view.forward[1]*r_view.forward[1]);
+ left[0] = -r_view.forward[1] * scale;
+ left[1] = r_view.forward[0] * scale;
+ left[2] = 0;
+ up[0] = 0;
+ up[1] = 0;
+ up[2] = ent->scale;
+ break;
+ case SPR_FACING_UPRIGHT:
+ // flames and such
+ // vertical beam sprite, faces viewer's origin (not the view plane)
+ scale = ent->scale / sqrt((org[0] - r_view.origin[0])*(org[0] - r_view.origin[0])+(org[1] - r_view.origin[1])*(org[1] - r_view.origin[1]));
+ left[0] = (org[1] - r_view.origin[1]) * scale;
+ left[1] = -(org[0] - r_view.origin[0]) * scale;
+ left[2] = 0;
+ up[0] = 0;
+ up[1] = 0;
+ up[2] = ent->scale;
+ break;
+ default:
+ Con_Printf("R_SpriteSetup: unknown sprite type %i\n", model->sprite.sprnum_type);
+ // fall through to normal sprite
+ case SPR_VP_PARALLEL:
+ // normal sprite
+ // faces view plane
+ VectorScale(r_view.left, ent->scale, left);
+ VectorScale(r_view.up, ent->scale, up);
+ break;
+ case SPR_ORIENTED:
+ // bullet marks on walls
+ // ignores viewer entirely
+ VectorCopy(mleft, left);
+ VectorCopy(mup, up);
+ break;
+ case SPR_VP_PARALLEL_ORIENTED:
+ // I have no idea what people would use this for...
+ // oriented relative to view space
+ // FIXME: test this and make sure it mimicks software
+ left[0] = mleft[0] * r_view.forward[0] + mleft[1] * r_view.left[0] + mleft[2] * r_view.up[0];
+ left[1] = mleft[0] * r_view.forward[1] + mleft[1] * r_view.left[1] + mleft[2] * r_view.up[1];
+ left[2] = mleft[0] * r_view.forward[2] + mleft[1] * r_view.left[2] + mleft[2] * r_view.up[2];
+ up[0] = mup[0] * r_view.forward[0] + mup[1] * r_view.left[0] + mup[2] * r_view.up[0];
+ up[1] = mup[0] * r_view.forward[1] + mup[1] * r_view.left[1] + mup[2] * r_view.up[1];
+ up[2] = mup[0] * r_view.forward[2] + mup[1] * r_view.left[2] + mup[2] * r_view.up[2];
+ break;
+ }