Move to the collision position before stopping

git-svn-id: svn://cook.msm.cam.ac.uk:745/thrust3d/thrust3d@85 84d2e878-0bd5-11dd-ad15-13eda11d74c5

1 files changed, 60 insertions, 45 deletions

diff --git a/src/physics.c b/src/physics.c
index c9f89f1..d163b01 100644
--- a/src/physics.c
+++ b/src/physics.c
@@ -88,7 +88,7 @@ int physics_point_is_inside_hull(GLfloat cx, GLfloat cy, GLfloat cz, GLfloat *fv
 
 int physics_will_collide_face(GLfloat sx, GLfloat sy, GLfloat sz, GLfloat vx, GLfloat vy, GLfloat vz,
 					GLfloat nx, GLfloat ny, GLfloat nz, GLfloat *fvert, int nfvert, Uint32 dt,
-					ModelInstance *obj) {
+					ModelInstance *obj, Uint32 *ttc) {
 
 	GLfloat px, py, pz;
 	GLfloat pdotn, sdotn, vdotn;
@@ -132,6 +132,7 @@ int physics_will_collide_face(GLfloat sx, GLfloat sy, GLfloat sz, GLfloat vx, GL
 	//	printf("Collision happens at t + %f\n", t);
 	//	exit(0);
 		
+		*ttc = t;
 		return 1;
 	
 	}
@@ -140,6 +141,63 @@ int physics_will_collide_face(GLfloat sx, GLfloat sy, GLfloat sz, GLfloat vx, GL
 	
 }
 
+static int physics_check_collide_all_faces(ModelInstance *obj, ModelInstance *other, Uint32 dt, int a,
+						GLfloat sx, GLfloat sy, GLfloat sz, GLfloat vx, GLfloat vy, GLfloat vz) {
+
+	const GLfloat nx = other->model->primitives[a]->normals[0];
+	const GLfloat ny = other->model->primitives[a]->normals[1];
+	const GLfloat nz = other->model->primitives[a]->normals[2];
+	
+	switch ( other->model->primitives[a]->type ) {
+	
+		case PRIMITIVE_QUADS : {
+			
+			/* Faces are quads */
+			int f;
+			
+			for ( f=0; f<other->model->primitives[a]->num_vertices/4; f++ ) {
+			
+				GLfloat face[3*4];
+				int q;
+				Uint32 ttc;
+				
+				for ( q=0; q<4; q++ ) {
+					face[3*q + 0] = other->x + other->model->primitives[a]->vertices[3*((4*f)+q) + 0];
+					face[3*q + 1] = other->y + other->model->primitives[a]->vertices[3*((4*f)+q) + 1];
+					face[3*q + 2] = other->z + other->model->primitives[a]->vertices[3*((4*f)+q) + 2];
+				}
+				
+				if ( physics_will_collide_face(sx, sy, sz, vx, vy, vz, nx, ny, nz, face, 4, dt, other, &ttc) != 0 ) {
+						
+					printf("collides with %s/%p\n", other->model->name, other);
+					
+					if ( (nx == 0.0) && (ny == 0.0) && ( nz == 1.0) ) {
+						obj->x += obj->vx * ttc;
+						obj->y += obj->vy * ttc;
+						obj->z += obj->vz * ttc;
+						obj->vz = 0.0;
+						obj->landed = 1;
+					} else {
+						obj->vx = -obj->vx;
+						obj->vy = -obj->vy;
+						obj->vz = -obj->vz;
+						obj->yawspeed = 0.0;
+					}
+					
+					return 1;	/* Don't waste time looking anywhere else */
+					
+				}
+			}
+			break;
+			
+		}
+	
+	}
+	
+	return 0;
+	
+}
+
 /* Return non-zero if 'obj' will collide with 'other' with 'dt' milliseconds */
 static int physics_check_collide(ModelInstance *obj, ModelInstance *other, Uint32 dt) {
 
@@ -164,50 +222,7 @@ static int physics_check_collide(ModelInstance *obj, ModelInstance *other, Uint3
 			
 			/* Consider all the primitives in 'other' */
 			for ( a=0; a<other->model->num_primitives; a++ ) {
-			
-				const GLfloat nx = other->model->primitives[a]->normals[0];
-				const GLfloat ny = other->model->primitives[a]->normals[1];
-				const GLfloat nz = other->model->primitives[a]->normals[2];
-				
-				switch ( other->model->primitives[a]->type ) {
-				
-					case PRIMITIVE_QUADS : {
-						
-						/* Faces are quads */
-						int f;
-						
-						for ( f=0; f<other->model->primitives[a]->num_vertices/4; f++ ) {
-						
-							GLfloat face[3*4];
-							int q;
-							
-							for ( q=0; q<4; q++ ) {
-								face[3*q + 0] = other->x + other->model->primitives[a]->vertices[3*((4*f)+q) + 0];
-								face[3*q + 1] = other->y + other->model->primitives[a]->vertices[3*((4*f)+q) + 1];
-								face[3*q + 2] = other->z + other->model->primitives[a]->vertices[3*((4*f)+q) + 2];
-							}
-							
-							if ( physics_will_collide_face(sx, sy, sz, vx, vy, vz, nx, ny, nz,
-											face, 4, dt, other) != 0 ) {
-									printf("collides with %s/%p\n", other->model->name, other);
-									if ( (nx == 0.0) && (ny == 0.0) && ( nz == 1.0) ) {
-										obj->vz = 0.0;
-										obj->landed = 1;
-									} else {
-										obj->vx = -obj->vx;
-										obj->vy = -obj->vy;
-										obj->vz = -obj->vz;
-										obj->yawspeed = 0.0;
-									}
-									return 1;	/* Don't waste time looking anywhere else */
-							}
-						}
-						break;
-						
-					}
-				
-				}
-			
+				if ( physics_check_collide_all_faces(obj, other, dt, a, sx, sy, sz, vx, vy, vz) ) return 1;
 			}
 			
 		}