iOS开发之360°/720°全景展示-天狐博客

360度平面旋转效果

360旋转效果,其实很简单,就是通过手势,使一imageview不停的换不同角度的图就行了.至于一张图对应多少度,多少度对应多少张图.可以适当的调节

关键代码

- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
    if ([event.allTouches count] == 1)
    {
        UITouch *touch = [touches anyObject];
        CGPoint lastPoint = [touch previousLocationInView:self];
        CGPoint nowPoint = [touch locationInView:self];
        
        CGFloat xOffset = nowPoint.x - lastPoint.x;
        CGFloat yOffset = nowPoint.y - lastPoint.y;
        CGPoint offset = CGPointMake(xOffset, yOffset);
        
        NSTimeInterval newitme = event.timestamp - _previousTouchTimestamp;
    
        if (newitme > 0.03)
        {
            if (offset.x < 0)
            {
                if (self.currentIndex < [_imagePaths count]-1?:0)
                {
                    self.currentIndex++;
                }
                else
                {
                    self.currentIndex = 0;
                }
            }
            else
            {
                if (self.currentIndex != 0)
                {
                    self.currentIndex--;
                }
                else
                {
                    self.currentIndex = [_imagePaths count]-1?:0;
                }
                
            }
            if (_didChangeBlock) {
                _didChangeBlock(self.currentIndex,(360.0/self.count)*self.currentIndex);
            }
            _previousTouchTimestamp = event.timestamp;
        }
    }
}

- (void)setCurrentIndex:(NSInteger)currentIndex
{
    if (!_imagePaths || [_imagePaths count]<=0) {
        return;
    }
    _currentIndex = MIN(MAX(0, currentIndex), self.count - 1) ;
    NSString *path = [_imagePaths objectAtIndex:_currentIndex];
    UIImage *image  = [UIImage imageWithContentsOfFile:path];
    [_imageView setImage:image];
}

720度全景效果

一张鱼眼图或者六方图，展现出来的全景影像效果图

PanoramaGL (支持一张鱼眼图或六方图)

PanoramaGL是世界上第一个开源的实现360度全景图像的iOS、Android类库。基于OpenGL 支持球,立方体，圆柱。有重力加速等。

很老的一个库了，但是效果做的非常棒，缺点就是非常耗内存，并且作者早已经不在维护了，bug非常多

https://code.google.com/p/panoramagl

本人在生产环境用了很久这个库，所以自己也fork了一个版本，修改了若干bug，满足基本使用

https://github.com/shaojiankui/PanoramaGL

JAPanoView （推荐,只支持六方图）

JAPanoView是一个UIView子类,从立方全景图像创建显示360 - 180度全景，交互式平移和缩放。可以添加任何UIView JAPanoView热点。类库非常棒，完全基于iOS类库实现，没有借助OpenGL

https://bitbucket.org/javieralonso/japanoview/

显然这个库也很久更新了，Bug也有些，偌大互联网也有人fork了下，修复了bug，

https://github.com/smartapps-fr/JAPanoView

Panorama (支持一张鱼眼图)

同样是基于OpenGL的球形全景视图，代码非常少，值得学习。但是只支持一张鱼眼图。

https://github.com/robbykraft/Panorama

threejs.org (支持一张鱼眼图或六方图)

Three.js 是一款运行在浏览器中的 3D 引擎，你可以用它创建各种三维场景，包括了摄影机、光影、材质等各种对象。你可以在它的主页上看到许多精彩的演示。不过，这款引擎目前还处在比较不成熟的开发阶段，其不够丰富的 API 以及匮乏的文档增加了初学者的学习难度（尤其是文档的匮乏）。但是显示在iOS Webview略显鸡肋。最后放弃之

three.js的代码托管在github上面

https://github.com/mrdoob/three.js

类库非常强大。全景展示仅仅是一个小功能

http://threejs.org/examples/webgl_panorama_equirectangular.html

OpenGL自己动手实现 (支持一张鱼眼图或六方图)

GLKit.framework 与OpenGLES

使用 GLKTextureLoader的cubeMapWithContentsOfFiles，textureWithContentsOfFile，textureWithCGImage 我们很容易渲染出来一个球体效果，难点就在于根据手势的拖动与缩放改变球体

关键代码

- (void)setupGL
{
    self.context = [[EAGLContext alloc] initWithAPI:kEAGLRenderingAPIOpenGLES3];
    
    GLKView *view = (GLKView*)self.view;
    view.context = self.context;
    view.drawableDepthFormat = GLKViewDrawableDepthFormat24;
    
    [EAGLContext setCurrentContext:self.context];
    
    self.skyboxEffect = GLKSkyboxEffect.new;
    
    glEnable(GL_DEPTH_TEST);
    
    
    NSArray *cubeMapFileNames = [NSArray arrayWithObjects:
                                 [[NSBundle mainBundle] pathForResource:@"right" ofType:@"png"],
                                 [[NSBundle mainBundle] pathForResource:@"left" ofType:@"png"],
                                 [[NSBundle mainBundle] pathForResource:@"up" ofType:@"png"],
                                 [[NSBundle mainBundle] pathForResource:@"down" ofType:@"png"],
                                 [[NSBundle mainBundle] pathForResource:@"front" ofType:@"png"],
                                 [[NSBundle mainBundle] pathForResource:@"back" ofType:@"png"],
                                 nil];
    
    NSError *error;
    NSDictionary *options = [NSDictionary dictionaryWithObject:[NSNumber numberWithBool:NO]
                                                        forKey:GLKTextureLoaderOriginBottomLeft];
    self.cubemap = [GLKTextureLoader cubeMapWithContentsOfFiles:cubeMapFileNames
                                                        options:options
                                                          error:&error];
    self.skyboxEffect.textureCubeMap.name = self.cubemap.name;
    
    glBindVertexArrayOES(0);
    
    _rotMatrix = GLKMatrix4Identity;
}

https://github.com/shaojiankui/Panorama-OpenGL

SceneKit自己动手实现

关键代码

NSString *imagePath = [[NSBundle mainBundle] pathForResource:@"park_2048" ofType:@"jpg"];
UIImage *image = [UIImage imageWithContentsOfFile:imagePath];

// Set the scene
self.sceneView.scene = [[SCNScene alloc]init];
self.sceneView.showsStatistics = YES;
self.sceneView.allowsCameraControl = YES;

//Create node, containing a sphere, using the panoramic image as a texture
SCNSphere *sphere =   [SCNSphere sphereWithRadius:20.0];
sphere.firstMaterial.doubleSided = YES;
sphere.firstMaterial.diffuse.contents = image;

SCNNode *sphereNode = [SCNNode nodeWithGeometry:sphere];
sphereNode.position = SCNVector3Make(0,0,0);
[self.sceneView.scene.rootNode addChildNode:sphereNode];


// Camera, ...
_cameraNode = [[SCNNode alloc]init];
_cameraNode.camera = [[SCNCamera alloc]init];
_cameraNode.position = SCNVector3Make(0, 0, 0);
[self.sceneView.scene.rootNode addChildNode:_cameraNode];

_motionManager = [[CMMotionManager alloc]init];

if (_motionManager.isDeviceMotionAvailable) {
    
    _motionManager.deviceMotionUpdateInterval = 1.0 / 60.0;
    [_motionManager startDeviceMotionUpdatesToQueue:[NSOperationQueue mainQueue] withHandler:^(CMDeviceMotion * _Nullable motion, NSError * _Nullable error) {
        
        CMAttitude *attitude = motion.attitude;
        
        _cameraNode.eulerAngles = SCNVector3Make(attitude.roll - M_PI/2.0, attitude.yaw, attitude.pitch);
    }];
}

https://github.com/shaojiankui/Panorama-SceneKit