从SKSpriteNode_01.pos开始的绘制线 - 以SKSpriteNode_02.pos结尾（并添加粒子）

Question

大家好我想知道在两个精灵之间绘制粒子系统线的最佳方法是什么（如果精灵位置移动轻推/重力等则会更新）

我试过这种方式（抱歉我的新手代码＆gt;＆lt;） 从obj01开始画线 - 以obj02结尾 到目前为止工作但我不知道如果精灵移动例如

如何更新线坐标

另一个相关的问题可能是因为没有更新pathToDraw，粒子系统似乎已经偏离了 所以我知道我需要更新它（如果有人可以写一个sudo代码/想法，我希望在哪里开始绘制路径，在哪里删除等，这对确定非常有帮助）

感谢N：）

-(void)drawLineFromObj2:(EnemyClass*)obj03 to:(EnemyClass*)obj04
{
    if (UFO02IsDead == NO && UFO03IsDead == NO)
    {
        if (ufo_02ReadyToLink == YES && ufo_03ReadyToLink == YES) {
            NSLog(@"Line from Obj2 to obj03");

           // **CreateLine**

    lineNode02.path = pathToDraw;
    lineNode02 = [SKShapeNode node];
    CGMutablePathRef pathToDraw = CGPathCreateMutable();
    CGPathMoveToPoint(pathToDraw, NULL, obj03.position.x, obj03.position.y);
    CGPathAddLineToPoint(pathToDraw, NULL, obj04.position.x, obj04.position.y);
    lineNode02.path = pathToDraw;

    //Add Particles
    NSString *myParticlePath = [[NSBundle mainBundle] pathForResource:@"ForceField" ofType:@"sks"];
    SKEmitterNode *myParticle = [NSKeyedUnarchiver unarchiveObjectWithFile:myParticlePath];
    [self addChild:myParticle];

//get particles to drop by adding physics? 
(this no effect the particles don't follow the line and don't seem

附加到它上面，如果精灵移动，它们也会改变位置）

//myParticle.physicsBody = [SKPhysicsBody bodyWithRectangleOfSize:self.frame.size];
//myParticle.physicsBody.affectedByGravity = YES;
//myParticle.physicsBody.allowsRotation = NO;

pathToDraw myParticle使用SKAction followPath：pathToDraw

如何更新pathToDraw以绘制平滑线条并正确删除最后一行

 SKAction *followTrack =
 [SKAction followPath:pathToDraw asOffset:NO orientToPath:YES duration:.5];
 SKAction *forever = [SKAction repeatActionForever:followTrack];
 myParticle.particleAction = forever;

 lineNode02.name = @"lineNode";
 [self addChild:lineNode02];

//is there a way to link the movement with the crystal positions and   animate the line length and angle (is there another way of doing this)


 //stops line being redrawn (but how to update when sprite is  moved, and how to delete the old lines?)
  ufo_03ReadyToLink = NO;


            }

        }
    }

Answer 1

通过将功能向下移动来修复它 - （无效）更新

创建了一个操作块

SKAction *remove = [SKAction removeFromParent];
    SKAction* blockAction = [SKAction runBlock:^
    {
        [self DrawLine]; //draws new line every update
        //then removes line
    }];
    [self runAction:[SKAction sequence:@[blockAction,remove]]];

也使用了纹理而不是粒子，但这就是我附加它的方式

//Add Particles
NSString *myParticlePath = 
[[NSBundle mainBundle] pathForResource:@"ForceField" ofType:@"sks"];
myParticle = [NSKeyedUnarchiver unarchiveObjectWithFile:myParticlePath];
[self addChild:myParticle];

SKAction *followTrack =
[SKAction followPath:pathToDraw asOffset:NO orientToPath:YES duration:.5];
SKAction *forever = [SKAction repeatActionForever:followTrack];
myParticle.particleAction = forever;

lineNode01.name = @"lineNode";
[self addChild:lineNode01];

希望它可以帮助别人：）