Implement OrbitalElement method to determine whether to collide

jmdetloff · May 26, 2013 · 3990d17 · 3990d17
1 parent f07da16
commit 3990d17
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Showing 4 changed files with 63 additions and 45 deletions.
diff --git a/GraceWorld/OneWayEdgeCollisionDetector.cpp b/GraceWorld/OneWayEdgeCollisionDetector.cpp
@@ -7,6 +7,7 @@
 //
 
 #import "Box2d/Box2D.h"
+#import "OrbitalElement.h"
 #import "OrbitalSurface.h"
 #import "OrbitalRect.h"
 #include "OneWayEdgeCollisionDetector.h"
@@ -21,14 +22,16 @@ int locationOfPointRelativeToEdge(b2Vec2 point, b2Body *edgeBody) {
 
 
 void OneWayEdgeCollisionDetector::BeginContact(b2Contact *contact) {
-    if (ContactIsFromBelow(contact)) {
+    b2Body *platformBody = this->GetBodyFromContact(contact, false);
+    OrbitalElement *platform = (__bridge OrbitalElement *)platformBody->GetUserData();
+
+    BOOL playerShouldCollide = [player shouldCollidePlayer:player withElement:platform contact:contact];
+    if (playerShouldCollide) {
         [player beginContact:contact];
     }
 
-    b2Body *platform = this->GetBodyFromContact(contact, false);
-    NSObject *obj = (__bridge NSObject *)platform->GetUserData();
-    if ([obj isKindOfClass:[OrbitalRect class]]) {
-        [(OrbitalRect *)obj boyBeganContact];
+    if ([platform isKindOfClass:[OrbitalRect class]]) {
+        [(OrbitalRect *)platform boyBeganContact];
     }
 }
 
@@ -57,8 +60,6 @@ void OneWayEdgeCollisionDetector::PreSolve(b2Contact* contact, const b2Manifold*
         return;
     }
 
-    bool solid = ContactIsFromBelow(contact);
-
     b2Body *platform = this->GetBodyFromContact(contact, false);
     OrbitalSurface *surface = (__bridge OrbitalSurface *)platform->GetUserData();
     if (surface) {
@@ -72,9 +73,9 @@ void OneWayEdgeCollisionDetector::PreSolve(b2Contact* contact, const b2Manifold*
         [surface boyMadeContactOnSide:direction];
     }
 
+    BOOL playerShouldCollide = [player shouldCollidePlayer:player withElement:surface contact:contact];
 
-    b2Vec2 boyVelocity = collidingBoy->GetLinearVelocity();
-    if (boyVelocity.y <= 0.01 && solid && (!surface || surface.allowsCollision)) {
+    if (playerShouldCollide && (!surface || surface.allowsCollision)) {
         return;
     }
 
@@ -100,36 +101,3 @@ b2Body* OneWayEdgeCollisionDetector::GetBodyFromContact(b2Contact *contact, bool
 
 void OneWayEdgeCollisionDetector::PostSolve(b2Contact* contact, const b2ContactImpulse* impulse) {
 }
-
-
-bool OneWayEdgeCollisionDetector::ContactIsFromBelow(b2Contact *contact) {
-    b2Vec2 boyPosition = player.physicsBody->GetPosition();
-    b2PolygonShape *boyShape = (b2PolygonShape *)player.physicsBody->GetFixtureList()->GetShape();
-
-    b2Vec2 lowestVertex = boyShape->GetVertex(0);
-    NSInteger vertexCount = boyShape->GetVertexCount();
-    for (int i = 1; i < vertexCount; i++) {
-        b2Vec2 vertex = boyShape->GetVertex(i);
-        if (vertex.y > lowestVertex.y) {
-            lowestVertex = vertex;
-        }
-    }
-
-    static const CGFloat footError = 0.2;
-    CGFloat footPosition = boyPosition.y - lowestVertex.y + footError;
-
-    int numPoints = contact->GetManifold()->pointCount;
-
-    BOOL solid = NO;
-
-    b2WorldManifold worldManifold;
-    contact->GetWorldManifold( &worldManifold );
-    for (int i = 0; i < numPoints; i++) {
-        if (worldManifold.points[i].y < footPosition) {
-            solid = YES;
-            break;
-        }
-    }
-
-    return solid;
-}
diff --git a/GraceWorld/OrbitalElement.h b/GraceWorld/OrbitalElement.h
@@ -9,9 +9,11 @@
 #import "Box2d/Box2d.h"
 #import <Foundation/Foundation.h>
 
-
+@class PlayerPhysicsWrapper;
 @interface OrbitalElement : NSObject
 
 @property (nonatomic, assign) b2Body *physicsBody;
 
-@end
+- (BOOL)shouldCollidePlayer:(PlayerPhysicsWrapper *)boy withElement:(OrbitalElement *)element contact:(b2Contact *)contact;
+
+@end
diff --git a/GraceWorld/OrbitalElement.m b/GraceWorld/OrbitalElement.m
@@ -10,4 +10,8 @@
 
 @implementation OrbitalElement
 
+- (BOOL)shouldCollidePlayer:(PlayerPhysicsWrapper *)boy withElement:(OrbitalElement *)element contact:(b2Contact *)contact {
+    return YES;
+}
+
 @end
diff --git a/GraceWorld/PlayerPhysicsWrapper.m b/GraceWorld/PlayerPhysicsWrapper.m
@@ -15,7 +15,7 @@ @implementation PlayerPhysicsWrapper {
     BOOL _standing;
 }
 
-- (id)initWithb2Body:(b2Body *)body {
+- (id)init {
     self = [super init];
     if (self) {
         _bottomContacts = [[NSMutableArray alloc] init];
@@ -24,6 +24,50 @@ - (id)initWithb2Body:(b2Body *)body {
 }
 
 
+- (BOOL)shouldCollidePlayer:(PlayerPhysicsWrapper *)boy withElement:(OrbitalElement *)element contact:(b2Contact *)contact {
+    if (contact->GetFixtureA() == _sensorFixture || contact->GetFixtureB() == _sensorFixture) {
+        return NO;
+    }
+
+    BOOL solid = [self contactIsFromBelow:contact];
+    b2Vec2 boyVelocity = self.physicsBody->GetLinearVelocity();
+    return (boyVelocity.y <= 0.01 && solid);
+}
+
+
+- (BOOL)contactIsFromBelow:(b2Contact *)contact {
+    b2Vec2 boyPosition = self.physicsBody->GetPosition();
+    b2PolygonShape *boyShape = (b2PolygonShape *)self.physicsBody->GetFixtureList()->GetShape();
+
+    b2Vec2 lowestVertex = boyShape->GetVertex(0);
+    NSInteger vertexCount = boyShape->GetVertexCount();
+    for (int i = 1; i < vertexCount; i++) {
+        b2Vec2 vertex = boyShape->GetVertex(i);
+        if (vertex.y > lowestVertex.y) {
+            lowestVertex = vertex;
+        }
+    }
+
+    static const CGFloat footError = 0.2;
+    CGFloat footPosition = boyPosition.y - lowestVertex.y + footError;
+
+    int numPoints = contact->GetManifold()->pointCount;
+
+    BOOL solid = NO;
+
+    b2WorldManifold worldManifold;
+    contact->GetWorldManifold( &worldManifold );
+    for (int i = 0; i < numPoints; i++) {
+        if (worldManifold.points[i].y < footPosition) {
+            solid = YES;
+            break;
+        }
+    }
+
+    return solid;
+}
+
+
 - (void)beginContact:(b2Contact *)contact {
     NSValue *val = [NSValue valueWithPointer:contact];
     [_bottomContacts addObject:val];