Question

我试图用滑动手势将SKTextureNode分割成碎片。我有进入和退出的坐标。

我如何使用它来分割节点？

Answer 1

我建议使用SKPhysicsJointFixed连接两个SKSpriteNodes以形成一个对象。当用户在对象上滑动时，您可以通过移除关节来分割它并施加冲动以相反的方向发送碎片。这是连接两个节点的方法：

- (void) connectNode1:(SKSpriteNode *)node1 toNode2:(SKSpriteNode *)node2
{
    CGPoint midPoint = CGPointMake((node1.position.x + node2.position.x)/2,
                                   (node1.position.y + node2.position.y)/2);

    SKPhysicsJointFixed *joint = [SKPhysicsJointFixed jointWithBodyA:node1.physicsBody
                                                               bodyB:node2.physicsBody
                                                              anchor:midPoint];
    [self.physicsWorld addJoint:joint];
}

这是一个如何在触摸时拆分对象的示例。这应该用滑动处理程序替换。

- (void) touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
    /* Called when a touch begins */

    for (UITouch *touch in touches) {
        CGPoint location = [touch locationInNode:self];

        // Determine which node was touched
        SKNode *touchedObject = [self nodeAtPoint:location];

        if (touchedObject == self) continue;

        // Check if node is connected
        if ([touchedObject.physicsBody.joints count]) {
            SKPhysicsJointFixed *joint = [touchedObject.physicsBody.joints firstObject];
            SKSpriteNode *node2 = (SKSpriteNode *)(touchedObject.physicsBody == joint.bodyA ?
                            joint.bodyB.node : joint.bodyA.node);

            [self.physicsWorld removeJoint:joint];
            CGFloat dx = touchedObject.position.x - node2.position.x;
            CGFloat dy = touchedObject.position.y - node2.position.y;

            CGFloat magnitude = sqrtf(dx*dx+dy*dy);

            // unit vector
            dx /= magnitude;
            dy /= magnitude;

            // send nodes in opposite directions
            [touchedObject.physicsBody applyImpulse:CGVectorMake(dx*20, dy*20)];
            [node2.physicsBody applyImpulse:CGVectorMake(-dx*20, -dy*20)];
        }
    }
}

Answer 2

在这种情况下，有一种与SKTexture相关的方法可以提供帮助。

[SKTexture textureWithRect:someRect inTexture:someTexture];

您可以通过根据坐标计算两个rects，并将它们分配给两个SKSpriteNode对象来使用此方法。

但是，这只能用于生成所讨论纹理的矩形切口。

另外，请查看documentation。

用滑动拆分SKTextureNode

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