我想在我的iPhone应用中将cocos3d的3D对象作为相机叠加物添加到增强现实中。我有一个带有一些模型的CC3Scene。我创建了motionManager捕获以获取有关设备相机方向的信息,然后在-(void)update:(ccTime)dt中尝试更新cocos3d场景中相机的位置(场景的上方向是Z轴):
-(void) update:(ccTime)dt
{
CMDeviceMotion *currentDeviceMotion = motionManager.deviceMotion;
CMAttitude *currentAttitude = currentDeviceMotion.attitude;
CC3Camera *cam = (CC3Camera*)[cc3Scene getNodeNamed:@"Camera"];
static double lastY = 0;
static double lastP = 0;
static double lastR = 0;
double yaw = CC_RADIANS_TO_DEGREES(currentAttitude.yaw-lastY);
double pitch = CC_RADIANS_TO_DEGREES(currentAttitude.pitch-lastP);
double roll = CC_RADIANS_TO_DEGREES(currentAttitude.roll-lastR);
CC3Vector fd = cc3v(0,1,0);
[cam rotateByAngle:roll aroundAxis:fd];
CC3Vector rp = cc3v(1,0,0);
[cam rotateByAngle:pitch aroundAxis:rp];
CC3Vector up = cc3v(0,0,1);
[cam rotateByAngle:yaw aroundAxis:up];
lastY = currentAttitude.yaw;
lastP = currentAttitude.pitch;
lastR = currentAttitude.roll;
[super update:dt];
}
我无法直接使用cam.rotation = cc3v(pitch, roll, yaw),因为cocos中旋转的顺序(使用我的当前坐标轴)与设备中的不匹配。但是,我的代码也不能正确工作。在手动旋转相机时出现错误,并且我不知道应该如何旋转它以使其正确(我已经尝试了几乎所有顺序和坐标轴的组合)。
所以问题是如何匹配cocos的相机旋转和设备的旋转?我有什么遗漏吗?或者您是否可以提供具有此类主题的代码或教程项目?我知道这是一个非常简单的问题,只涉及三角学,但我一直在想办法却无解。
谢谢!