Polygon subdivision, spotlight testing

git-svn-id: svn://cook.msm.cam.ac.uk:745/thrust3d/thrust3d@34 84d2e878-0bd5-11dd-ad15-13eda11d74c5

1 files changed, 123 insertions, 1 deletions

diff --git a/src/model.c b/src/model.c
index 5607e95..bd5ea5f 100644
--- a/src/model.c
+++ b/src/model.c
@@ -26,7 +26,7 @@
 #include "render.h"
 
 /* Maximum number of vertices per primitive */
-#define MAX_VERTICES 4096
+#define MAX_VERTICES 8192*5
 
 ModelContext *model_init() {
 
@@ -253,6 +253,128 @@ static int model_load(ModelContext *ctx, const char *name, RenderContext *render
 			}
 		}
 		
+		/* Subdivide the previous face if requested */
+		if ( sscanf(line, "subdivide %f %f", &x, &y) == 2 ) {
+			if ( type == PRIMITIVE_QUADS ) {
+				if ( (num_vertices % 4)==0 ) {
+					GLfloat u, v;
+					GLfloat v1x, v1y, v1z;
+					GLfloat v2x, v2y, v2z;
+					GLfloat v3x, v3y, v3z;
+					GLfloat v4x, v4y, v4z;
+					GLfloat nx, ny, nz;
+					GLfloat t1x, t1y;
+					GLfloat t2x, t2y;
+					GLfloat t3x, t3y;
+					GLfloat t4x, t4y;
+					nx = normals[3*(num_vertices-1) + 0];
+					ny = normals[3*(num_vertices-1) + 1];
+					nz = normals[3*(num_vertices-1) + 2];
+					v4x = vertices[3*(num_vertices-1) + 0];
+					v4y = vertices[3*(num_vertices-1) + 1];
+					v4z = vertices[3*(num_vertices-1) + 2];
+					v3x = vertices[3*(num_vertices-2) + 0];
+					v3y = vertices[3*(num_vertices-2) + 1];
+					v3z = vertices[3*(num_vertices-2) + 2];
+					v2x = vertices[3*(num_vertices-3) + 0];
+					v2y = vertices[3*(num_vertices-3) + 1];
+					v2z = vertices[3*(num_vertices-3) + 2];
+					v1x = vertices[3*(num_vertices-4) + 0];
+					v1y = vertices[3*(num_vertices-4) + 1];
+					v1z = vertices[3*(num_vertices-4) + 2];
+					t4x = texcoords[2*(num_vertices-1) + 0];
+					t4y = texcoords[2*(num_vertices-1) + 1];
+					t3x = texcoords[2*(num_vertices-2) + 0];
+					t3y = texcoords[2*(num_vertices-2) + 1];
+					t2x = texcoords[2*(num_vertices-3) + 0];
+					t2y = texcoords[2*(num_vertices-3) + 1];
+					t1x = texcoords[2*(num_vertices-4) + 0];
+					t1y = texcoords[2*(num_vertices-4) + 1];
+					if ( num_vertices - 4 + x*y*4 > MAX_VERTICES ) {
+						fprintf(stderr, "Not enough free vertex space to subdivide face\n");
+					}
+					num_vertices -= 4;
+					for ( u=0; u<x; u++ ) {
+						for ( v=0; v<y; v++ ) {
+							GLfloat l1x, l1y, l1z;
+							GLfloat l2x, l2y, l2z;
+							GLfloat l3x, l3y, l3z;
+							GLfloat l4x, l4y, l4z;
+							GLfloat tl1x, tl1y;
+							GLfloat tl2x, tl2y;
+							GLfloat tl3x, tl3y;
+							GLfloat tl4x, tl4y;
+							/* Interpolate vertices */
+							l1x = v1x + u*(v2x-v1x)/x;
+							l1y = v1y + u*(v2y-v1y)/x;
+							l1z = v1z + u*(v2z-v1z)/x;
+							l2x = v4x + u*(v3x-v4x)/x;
+							l2y = v4y + u*(v3y-v4y)/x;
+							l2z = v4z + u*(v3z-v4z)/x;
+							l3x = v1x + (u+1)*(v2x-v1x)/x;
+							l3y = v1y + (u+1)*(v2y-v1y)/x;
+							l3z = v1z + (u+1)*(v2z-v1z)/x;
+							l4x = v4x + (u+1)*(v3x-v4x)/x;
+							l4y = v4y + (u+1)*(v3y-v4y)/x;
+							l4z = v4z + (u+1)*(v3z-v4z)/x;
+							/* Interpolate texture coords */
+							tl1x = t1x + u*(t2x-t1x)/x;
+							tl1y = t1y + u*(t2y-t1y)/x;
+							tl2x = t4x + u*(t3x-t4x)/x;
+							tl2y = t4y + u*(t3y-t4y)/x;
+							tl3x = t1x + (u+1)*(t2x-t1x)/x;
+							tl3y = t1y + (u+1)*(t2y-t1y)/x;
+							tl4x = t4x + (u+1)*(t3x-t4x)/x;
+							tl4y = t4y + (u+1)*(t3y-t4y)/x;
+							/* Calculate vertices */
+							vertices[3*num_vertices+0] = l1x + v*(l2x-l1x)/y;
+							vertices[3*num_vertices+1] = l1y + v*(l2y-l1y)/y;
+							vertices[3*num_vertices+2] = l1z + v*(l2z-l1z)/y;
+							texcoords[2*num_vertices+0] = tl1x + v*(tl2x-tl1x)/y;
+							texcoords[2*num_vertices+1] = tl1y + v*(tl2y-tl1y)/y;
+							normals[3*num_vertices+0] = nx;
+							normals[3*num_vertices+1] = ny;
+							normals[3*num_vertices+2] = nz;
+							num_vertices++;
+							vertices[3*num_vertices+0] = l3x + v*(l4x-l3x)/y;
+							vertices[3*num_vertices+1] = l3y + v*(l4y-l3y)/y;
+							vertices[3*num_vertices+2] = l3z + v*(l4z-l3z)/y;
+							texcoords[2*num_vertices+0] = tl3x + v*(tl4x-tl3x)/y;
+							texcoords[2*num_vertices+1] = tl3y + v*(tl4y-tl3y)/y;
+							normals[3*num_vertices+0] = nx;
+							normals[3*num_vertices+1] = ny;
+							normals[3*num_vertices+2] = nz;
+							num_vertices++;
+							vertices[3*num_vertices+0] = l3x + (v+1)*(l4x-l3x)/y;
+							vertices[3*num_vertices+1] = l3y + (v+1)*(l4y-l3y)/y;
+							vertices[3*num_vertices+2] = l3z + (v+1)*(l4z-l3z)/y;
+							texcoords[2*num_vertices+0] = tl3x + v*(tl4x-tl3x)/y;
+							texcoords[2*num_vertices+1] = tl3y + v*(tl4y-tl3y)/y;
+							normals[3*num_vertices+0] = nx;
+							normals[3*num_vertices+1] = ny;
+							normals[3*num_vertices+2] = nz;
+							num_vertices++;
+							vertices[3*num_vertices+0] = l1x + (v+1)*(l2x-l1x)/y;
+							vertices[3*num_vertices+1] = l1y + (v+1)*(l2y-l1y)/y;
+							vertices[3*num_vertices+2] = l1z + (v+1)*(l2z-l1z)/y;
+							texcoords[2*num_vertices+0] = tl1x + v*(tl2x-tl1x)/y;
+							texcoords[2*num_vertices+1] = tl1y + v*(tl2y-tl1y)/y;
+							normals[3*num_vertices+0] = nx;
+							normals[3*num_vertices+1] = ny;
+							normals[3*num_vertices+2] = nz;
+							num_vertices++;
+						}
+					}
+				} else {
+					fprintf(stderr, "'subdivide' directive must come at a quad boundary\n");
+					return 1;
+				}
+			} else {
+				fprintf(stderr, "Can't subdivide this type of primitive\n");
+				return 1;
+			}
+		}
+		
 		if ( sscanf(line, "pulse %f %f %f", &r, &g, &b) == 3 ) {
 			attribs = attribs | ATTRIB_COLOUR;
 			attribs = attribs | ATTRIB_PULSE;