效果图.png
项目结构.png
核心代码：
#import "LongLegHelper.h"
#import "LongLegVertexAttribArrayBuffer.h"
#import "LongLegView.h"
// 初始纹理高度占控件高度的比例
static CGFloat const kDefaultOriginTextureHeight = 0.7f;
// 顶点数量
static NSInteger const kVerticesCount = 8;
//SenceVertex 结构体
typedef struct {
GLKVector3 positionCoord; //顶点坐标;
GLKVector2 textureCoord; //纹理坐标;
} SenceVertex;
@interface LongLegView () <GLKViewDelegate>
//Effect
@property (nonatomic, strong) GLKBaseEffect *baseEffect;
//顶点;
@property (nonatomic, assign) SenceVertex *vertices;
//顶点数组缓存区;
@property (nonatomic, strong) LongLegVertexAttribArrayBuffer *vertexAttribArrayBuffer;
//当前图片Size;
@property (nonatomic, assign) CGSize currentImageSize;
//是否有发现修改;
@property (nonatomic, assign, readwrite) BOOL hasChange;
//当前纹理的width;
@property (nonatomic, assign) CGFloat currentTextureWidth;
//临时创建的帧缓存和纹理缓存
@property (nonatomic, assign) GLuint tmpFrameBuffer;
@property (nonatomic, assign) GLuint tmpTexture;
// 用于重新绘制纹理
//当前纹理Y的开始位置;
@property (nonatomic, assign) CGFloat currentTextureStartY;
//当前纹理Y的结束位置;
@property (nonatomic, assign) CGFloat currentTextureEndY;
//当前纹理新的高度;
@property (nonatomic, assign) CGFloat currentNewHeight;
@end
@implementation LongLegView
//销毁
- (void)dealloc {
//销毁context
if ([EAGLContext currentContext] == self.context) {
[EAGLContext setCurrentContext:nil];
}
//销毁_vertices
if (_vertices) {
free(_vertices);
_vertices = nil;
}
//销毁帧缓存区
if (_tmpFrameBuffer) {
glDeleteFramebuffers(1, &_tmpFrameBuffer);
_tmpFrameBuffer = 0;
}
//销毁纹理
if (_tmpTexture) {
glDeleteTextures(1, &_tmpTexture);
_tmpTexture = 0;
}
}
//初始化
- (instancetype)initWithFrame:(CGRect)frame {
self = [super initWithFrame:frame];
if (self) {
[self commonInit];
}
return self;
}
//初始化
- (instancetype)initWithCoder:(NSCoder *)aDecoder {
self = [super initWithCoder:aDecoder];
if (self) {
[self commonInit];
}
return self;
}
#pragma mark - Public
/**
将区域拉伸或压缩为某个高度
@param startY 开始的纵坐标位置（相对于纹理）
@param endY 结束的纵坐标位置（相对于纹理）
@param newHeight 新的中间区域高度（相对于纹理）
*/
- (void)stretchingFromStartY:(CGFloat)startY
toEndY:(CGFloat)endY
withNewHeight:(CGFloat)newHeight {
self.hasChange = YES;
// 根据当前控件的尺寸和纹理的尺寸，计算初始纹理坐标
[self calculateOriginTextureCoordWithTextureSize:self.currentImageSize
startY:startY
endY:endY
newHeight:newHeight];
// 更新顶点数组缓存区的数据
[self.vertexAttribArrayBuffer updateDataWithAttribStride:sizeof(SenceVertex)
numberOfVertices:kVerticesCount
data:self.vertices
usage:GL_STATIC_DRAW];
// 显示
[self display];
// Change改变完毕之后, 通知ViewController 的 SpringView拉伸区域修改
if (self.springDelegate &&
[self.springDelegate respondsToSelector:@selector(springViewStretchAreaDidChanged:)]) {
[self.springDelegate springViewStretchAreaDidChanged:self];
}
}
// 纹理顶部的纵坐标 0～1
- (CGFloat)textureTopY {
//(1-vertices[0].顶点坐标的Y值)/2
CGFloat textureTopYValue = (1 - self.vertices[0].positionCoord.y) / 2;
return textureTopYValue;
}
// 纹理底部的纵坐标 0～1
- (CGFloat)textureBottomY {
//(1-vertices[7].顶点坐标的Y值)/2
CGFloat textureBottomYValue = (1 - self.vertices[7].positionCoord.y) / 2;
return textureBottomYValue;
}
// 可伸缩区域顶部的纵坐标 0～1
- (CGFloat)stretchAreaTopY {
CGFloat stretchAreaTopYValue = (1 - self.vertices[2].positionCoord.y) / 2;
return stretchAreaTopYValue;
}
// 可伸缩区域底部的纵坐标 0～1
- (CGFloat)stretchAreaBottomY {
CGFloat stretchAreaBottomYValue = (1 - self.vertices[5].positionCoord.y) / 2;
return stretchAreaBottomYValue;
}
// 纹理高度 0～1
- (CGFloat)textureHeight {
CGFloat textureHeightValue = self.textureBottomY - self.textureTopY;
return textureHeightValue;
}
//从帧缓存区中获取纹理图片文件; 获取当前的渲染结果
- (UIImage *)createResult {
//1. 根据屏幕上显示结果, 重新获取顶点/纹理坐标
[self resetTextureWithOriginWidth:self.currentImageSize.width
originHeight:self.currentImageSize.height
topY:self.currentTextureStartY
bottomY:self.currentTextureEndY
newHeight:self.currentNewHeight];
//2.绑定帧缓存区;
glBindFramebuffer(GL_FRAMEBUFFER, self.tmpFrameBuffer);
//3.获取新的图片Size
CGSize imageSize = [self newImageSize];
//4.从帧缓存中获取拉伸后的图片;
UIImage *image = [self imageFromTextureWithWidth:imageSize.width height:imageSize.height];
//5. 将帧缓存绑定0,清空;
glBindFramebuffer(GL_FRAMEBUFFER, 0);
//6. 返回拉伸后的图片
return image;
}
// 根据当前的拉伸结果来重新生成纹理
- (void)updateTexture {
[self resetTextureWithOriginWidth:self.currentImageSize.width
originHeight:self.currentImageSize.height
topY:self.currentTextureStartY
bottomY:self.currentTextureEndY
newHeight:self.currentNewHeight];
//1.设置新的纹理
if (self.baseEffect.texture2d0.name != 0) {
//获取原始的纹理ID
GLuint textureName = self.baseEffect.texture2d0.name;
//删除纹理
glDeleteTextures(1, &textureName);
}
//2.重新设置新的纹理ID;
self.baseEffect.texture2d0.name = self.tmpTexture;
//3. 重置图片的尺寸
self.currentImageSize = [self newImageSize];
self.hasChange = NO;
//4. 更新纹理的顶点/纹理坐标信息;
[self calculateOriginTextureCoordWithTextureSize:self.currentImageSize
startY:0
endY:0
newHeight:0];
//5. 更新顶点数组缓存里的顶点/纹理坐标数据;
[self.vertexAttribArrayBuffer updateDataWithAttribStride:sizeof(SenceVertex)
numberOfVertices:kVerticesCount
data:self.vertices
usage:GL_STATIC_DRAW];
//6. 显示;
[self display];
}
// 更新图片
- (void)updateImage:(UIImage *)image {
//记录SpringView是否发生拉伸动作
self.hasChange = NO;
//1.GLKTextureInfo 设置纹理参数
NSDictionary *options = @{GLKTextureLoaderOriginBottomLeft : @(YES)};
GLKTextureInfo *textureInfo = [GLKTextureLoader textureWithCGImage:[image CGImage]
options:options
error:NULL];
//2.创建GLKBaseEffect 方法.
self.baseEffect = [[GLKBaseEffect alloc] init];
self.baseEffect.texture2d0.name = textureInfo.name;
//3.记录当前图片的size = 图片本身的size;
self.currentImageSize = image.size;
//4.计算出图片的宽高比例
CGFloat ratio = (self.currentImageSize.height / self.currentImageSize.width) *
(self.bounds.size.width / self.bounds.size.height);
//5. 获取纹理的高度;
CGFloat textureHeight = MIN(ratio, kDefaultOriginTextureHeight);
//6. 根据纹理的高度以及宽度, 计算出图片合理的宽度;
self.currentTextureWidth = textureHeight / ratio;
//7.根据当前控件的尺寸以及纹理的尺寸,计算纹理坐标以及顶点坐标;
[self calculateOriginTextureCoordWithTextureSize:self.currentImageSize
startY:0
endY:0
newHeight:0];
//8. 更新顶点数组缓存区;
[self.vertexAttribArrayBuffer updateDataWithAttribStride:sizeof(SenceVertex)
numberOfVertices:kVerticesCount
data:self.vertices
usage:GL_STATIC_DRAW];
//9. 显示(绘制)
[self display];
}
#pragma mark - Private
//初始化
- (void)commonInit {
//1.初始化vertices,context
self.vertices = malloc(sizeof(SenceVertex) * kVerticesCount);
self.backgroundColor = [UIColor clearColor];
self.context = [[EAGLContext alloc] initWithAPI:kEAGLRenderingAPIOpenGLES2];
self.delegate = self;
[EAGLContext setCurrentContext:self.context];
glClearColor(0, 0, 0, 0);
//2.初始化vertexAttribArrayBuffer
self.vertexAttribArrayBuffer = [[LongLegVertexAttribArrayBuffer alloc] initWithAttribStride:sizeof(SenceVertex) numberOfVertices:kVerticesCount data:self.vertices usage:GL_STATIC_DRAW];
}
/**
根据当前控件的尺寸和纹理的尺寸，计算初始纹理坐标
@param size 原始纹理尺寸
@param startY 中间区域的开始纵坐标位置 0~1
@param endY 中间区域的结束纵坐标位置 0~1
@param newHeight 新的中间区域的高度
*/
- (void)calculateOriginTextureCoordWithTextureSize:(CGSize)size
startY:(CGFloat)startY
endY:(CGFloat)endY
newHeight:(CGFloat)newHeight {
NSLog(@"%f,%f",size.height,size.width);
//1. 计算拉伸后的宽高比;
CGFloat ratio = (size.height / size.width) *
(self.bounds.size.width / self.bounds.size.height);
//2. 宽度=纹理本身宽度;
CGFloat textureWidth = self.currentTextureWidth;
//3. 高度=纹理高度*radio(宽高比)
CGFloat textureHeight = textureWidth * ratio;
NSLog(@"%f,%f,%f,%f",newHeight,endY,startY,textureHeight);
//4. 拉伸量 (newHeight - (endY-startY)) * 纹理高度;
CGFloat delta = (newHeight - (endY - startY)) * textureHeight;
//5. 判断纹理高度+拉伸量是否超出最大值1
if (textureHeight + delta >= 1) {
delta = 1 - textureHeight;
newHeight = delta / textureHeight + (endY - startY);
}
//6. 纹理4个角的顶点
// 左上角
GLKVector3 pointLT = {-textureWidth, textureHeight + delta, 0};
// 右上角
GLKVector3 pointRT = {textureWidth, textureHeight + delta, 0};
// 左下角
GLKVector3 pointLB = {-textureWidth, -textureHeight - delta, 0};
// 右下角
GLKVector3 pointRB = {textureWidth, -textureHeight - delta, 0};
// 中间矩形区域的顶点
//0.7 - 2 * 0.7 * 0.25
CGFloat tempStartYCoord = textureHeight - 2 * textureHeight * startY;
CGFloat tempEndYCoord = textureHeight - 2 * textureHeight * endY;
CGFloat startYCoord = MIN(tempStartYCoord, textureHeight);
CGFloat endYCoord = MAX(tempEndYCoord, -textureHeight);
// 中间部分左上角
GLKVector3 centerPointLT = {-textureWidth, startYCoord + delta, 0};
// 中间部分右上角
GLKVector3 centerPointRT = {textureWidth, startYCoord + delta, 0};
// 中间部分左下角
GLKVector3 centerPointLB = {-textureWidth, endYCoord - delta, 0};
// 中间部分右下角
GLKVector3 centerPointRB = {textureWidth, endYCoord - delta, 0};
//--纹理的上面两个顶点
//顶点V0的顶点坐标以及纹理坐标;
self.vertices[0].positionCoord = pointRT;
self.vertices[0].textureCoord = GLKVector2Make(1, 1);
//顶点V1的顶点坐标以及纹理坐标;
self.vertices[1].positionCoord = pointLT;
self.vertices[1].textureCoord = GLKVector2Make(0, 1);
//--中间区域的4个顶点
//顶点V2的顶点坐标以及纹理坐标;
self.vertices[2].positionCoord = centerPointRT;
self.vertices[2].textureCoord = GLKVector2Make(1, 1 - startY);
//顶点V3的顶点坐标以及纹理坐标;
self.vertices[3].positionCoord = centerPointLT;
self.vertices[3].textureCoord = GLKVector2Make(0, 1 - startY);
//顶点V4的顶点坐标以及纹理坐标;
self.vertices[4].positionCoord = centerPointRB;
self.vertices[4].textureCoord = GLKVector2Make(1, 1 - endY);
//顶点V5的顶点坐标以及纹理坐标;
self.vertices[5].positionCoord = centerPointLB;
self.vertices[5].textureCoord = GLKVector2Make(0, 1 - endY);
// 纹理的下面两个顶点
//顶点V6的顶点坐标以及纹理坐标;
self.vertices[6].positionCoord = pointRB;
self.vertices[6].textureCoord = GLKVector2Make(1, 0);
//顶点V7的顶点坐标以及纹理坐标;
self.vertices[7].positionCoord = pointLB;
self.vertices[7].textureCoord = GLKVector2Make(0, 0);
// 保存临时值
self.currentTextureStartY = startY;
self.currentTextureEndY = endY;
self.currentNewHeight = newHeight;
}
/**
根据当前屏幕上的显示，来重新创建纹理
@param originWidth 纹理的原始实际宽度
@param originHeight 纹理的原始实际高度
@param topY 0 ~ 1，拉伸区域的顶边的纵坐标
@param bottomY 0 ~ 1，拉伸区域的底边的纵坐标
@param newHeight 0 ~ 1，拉伸区域的新高度
*/
- (void)resetTextureWithOriginWidth:(CGFloat)originWidth
originHeight:(CGFloat)originHeight
topY:(CGFloat)topY
bottomY:(CGFloat)bottomY
newHeight:(CGFloat)newHeight {
//1.新的纹理尺寸(新纹理图片的宽高)
GLsizei newTextureWidth = originWidth;
GLsizei newTextureHeight = originHeight * (newHeight - (bottomY - topY)) + originHeight;
//2.高度变化百分比
CGFloat heightScale = newTextureHeight / originHeight;
//3.在新的纹理坐标下，重新计算topY、bottomY
CGFloat newTopY = topY / heightScale;
CGFloat newBottomY = (topY + newHeight) / heightScale;
//4.创建顶点数组与纹理数组(逻辑与calculateOriginTextureCoordWithTextureSize 中关于纹理坐标以及顶点坐标逻辑是一模一样的)
SenceVertex *tmpVertices = malloc(sizeof(SenceVertex) * kVerticesCount);
tmpVertices[0] = (SenceVertex){{-1, 1, 0}, {0, 1}};
tmpVertices[1] = (SenceVertex){{1, 1, 0}, {1, 1}};
tmpVertices[2] = (SenceVertex){{-1, -2 * newTopY + 1, 0}, {0, 1 - topY}};
tmpVertices[3] = (SenceVertex){{1, -2 * newTopY + 1, 0}, {1, 1 - topY}};
tmpVertices[4] = (SenceVertex){{-1, -2 * newBottomY + 1, 0}, {0, 1 - bottomY}};
tmpVertices[5] = (SenceVertex){{1, -2 * newBottomY + 1, 0}, {1, 1 - bottomY}};
tmpVertices[6] = (SenceVertex){{-1, -1, 0}, {0, 0}};
tmpVertices[7] = (SenceVertex){{1, -1, 0}, {1, 0}};
///下面开始渲染到纹理的流程
//1. 生成帧缓存区;
GLuint frameBuffer;
GLuint texture;
//glGenFramebuffers 生成帧缓存区对象名称;
glGenFramebuffers(1, &frameBuffer);
//glBindFramebuffer 绑定一个帧缓存区对象;
glBindFramebuffer(GL_FRAMEBUFFER, frameBuffer);
//2. 生成纹理ID,绑定纹理;
//glGenTextures 生成纹理ID
glGenTextures(1, &texture);
//glBindTexture 将一个纹理绑定到纹理目标上;
glBindTexture(GL_TEXTURE_2D, texture);
//glTexImage2D 指定一个二维纹理图像;
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, newTextureWidth, newTextureHeight, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL);
//3. 设置纹理相关参数
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
//4. 将纹理图像加载到帧缓存区对象上;
/*
glFramebufferTexture2D (GLenum target, GLenum attachment, GLenum textarget, GLuint texture, GLint level)
target: 指定帧缓冲目标,符合常量必须是GL_FRAMEBUFFER;
attachment: 指定附着纹理对象的附着点GL_COLOR_ATTACHMENT0
textarget: 指定纹理目标, 符合常量:GL_TEXTURE_2D
teture: 指定要附加图像的纹理对象;
level: 指定要附加的纹理图像的mipmap级别，该级别必须为0。
*/
glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, texture, 0);
//5. 设置视口尺寸
glViewport(0, 0, newTextureWidth, newTextureHeight);
//6. 获取着色器程序
GLuint program = [LongLegHelper programWithShaderName:@"spring"];
glUseProgram(program);
//7. 获取参数ID
GLuint positionSlot = glGetAttribLocation(program, "Position");
GLuint textureSlot = glGetUniformLocation(program, "Texture");
GLuint textureCoordsSlot = glGetAttribLocation(program, "TextureCoords");
//8. 传值
glActiveTexture(GL_TEXTURE0);
glBindTexture(GL_TEXTURE_2D, self.baseEffect.texture2d0.name);
glUniform1i(textureSlot, 0);
//9.初始化缓存区
LongLegVertexAttribArrayBuffer *vbo = [[LongLegVertexAttribArrayBuffer alloc] initWithAttribStride:sizeof(SenceVertex) numberOfVertices:kVerticesCount data:tmpVertices usage:GL_STATIC_DRAW];
//10.准备绘制,将纹理/顶点坐标传递进去;
[vbo prepareToDrawWithAttrib:positionSlot numberOfCoordinates:3 attribOffset:offsetof(SenceVertex, positionCoord) shouldEnable:YES];
[vbo prepareToDrawWithAttrib:textureCoordsSlot numberOfCoordinates:2 attribOffset:offsetof(SenceVertex, textureCoord) shouldEnable:YES];
//11. 绘制
[vbo drawArrayWithMode:GL_TRIANGLE_STRIP startVertexIndex:0 numberOfVertices:kVerticesCount];
//12.解绑缓存
glBindFramebuffer(GL_FRAMEBUFFER, 0);
//13.释放顶点数组
free(tmpVertices);
//14.保存临时的纹理对象/帧缓存区对象;
self.tmpTexture = texture;
self.tmpFrameBuffer = frameBuffer;
}
// 返回某个纹理对应的 UIImage，调用前先绑定对应的帧缓存
- (UIImage *)imageFromTextureWithWidth:(int)width height:(int)height {
//1.绑定帧缓存区;
glBindFramebuffer(GL_FRAMEBUFFER, self.tmpFrameBuffer);
//2.将帧缓存区内的图片纹理绘制到图片上;
int size = width * height * 4;
GLubyte *buffer = malloc(size);
/*
glReadPixels (GLint x, GLint y, GLsizei width, GLsizei height, GLenum format, GLenum type, GLvoid* pixels);
@功能: 读取像素(理解为将已经绘制好的像素,从显存中读取到内存中;)
@参数解读:
参数x,y,width,height: xy坐标以及读取的宽高;
参数format: 颜色格式; GL_RGBA;
参数type: 读取到的内容保存到内存所用的格式;GL_UNSIGNED_BYTE 会把数据保存为GLubyte类型;
参数pixels: 指针,像素数据读取后, 将会保存到该指针指向的地址内存中;
注意: pixels指针,必须保证该地址有足够的可以使用的空间, 以容纳读取的像素数据; 例如一副256 * 256的图像,如果读取RGBA 数据, 且每个数据保存在GLUbyte. 总大小就是 256 * 256 * 4 = 262144字节, 即256M;
int size = width * height * 4;
GLubyte *buffer = malloc(size);
*/
glReadPixels(0, 0, width, height, GL_RGBA, GL_UNSIGNED_BYTE, buffer);
//使用data和size 数组来访问buffer数据;
/*
CGDataProviderRef CGDataProviderCreateWithData(void *info, const void *data, size_t size, CGDataProviderReleaseDataCallback releaseData);
@功能: 新的数据类型, 方便访问二进制数据;
@参数:
参数info: 指向任何类型数据的指针, 或者为Null;
参数data: 数据存储的地址,buffer
参数size: buffer的数据大小;
参数releaseData: 释放的回调,默认为空;
*/
CGDataProviderRef provider = CGDataProviderCreateWithData(NULL, buffer, size, NULL);
//每个组件的位数;
int bitsPerComponent = 8;
//像素占用的比特数4 * 8 = 32;
int bitsPerPixel = 32;
//每一行的字节数
int bytesPerRow = 4 * width;
//颜色空间格式;
CGColorSpaceRef colorSpaceRef = CGColorSpaceCreateDeviceRGB();
//位图图形的组件信息 - 默认的
CGBitmapInfo bitmapInfo = kCGBitmapByteOrderDefault;
//颜色映射
CGColorRenderingIntent renderingIntent = kCGRenderingIntentDefault;
//3.将帧缓存区里像素点绘制到一张图片上;
/*
CGImageCreate(size_t width, size_t height,size_t bitsPerComponent, size_t bitsPerPixel, size_t bytesPerRow,CGColorSpaceRef space, CGBitmapInfo bitmapInfo, CGDataProviderRef provider,const CGFloat decode[], bool shouldInterpolate,CGColorRenderingIntent intent);
@功能:根据你提供的数据创建一张位图;
注意:size_t 定义的是一个可移植的单位,在64位机器上为8字节,在32位机器上是4字节;
参数width: 图片的宽度像素;
参数height: 图片的高度像素;
参数bitsPerComponent: 每个颜色组件所占用的位数, 比如R占用8位;
参数bitsPerPixel: 每个颜色的比特数, 如果是RGBA则是32位, 4 * 8 = 32位;
参数bytesPerRow :每一行占用的字节数;
参数space:颜色空间模式,CGColorSpaceCreateDeviceRGB
参数bitmapInfo:kCGBitmapByteOrderDefault 位图像素布局;
参数provider: 图片数据源提供者, 在CGDataProviderCreateWithData ,将buffer 转为 provider 对象;
参数decode: 解码渲染数组, 默认NULL
参数shouldInterpolate: 是否抗锯齿;
参数intent: 图片相关参数;kCGRenderingIntentDefault
*/
CGImageRef imageRef = CGImageCreate(width, height, bitsPerComponent, bitsPerPixel, bytesPerRow, colorSpaceRef, bitmapInfo, provider, NULL, NO, renderingIntent);
//4. 此时的 imageRef 是上下颠倒的，调用 CG 的方法重新绘制一遍，刚好翻转过来
//创建一个图片context
UIGraphicsBeginImageContext(CGSizeMake(width, height));
CGContextRef context = UIGraphicsGetCurrentContext();
//将图片绘制上去
CGContextDrawImage(context, CGRectMake(0, 0, width, height), imageRef);
//从context中获取图片
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
//结束图片context处理
UIGraphicsEndImageContext();
//释放buffer
free(buffer);
//返回图片
return image;
}
// 根据当前屏幕的尺寸，返回新的图片尺寸
- (CGSize)newImageSize {
//新图片的尺寸 = 当前图片的高 * (当前图片高度 - (当前纹理EndY - 当前纹理Star))+1;
CGFloat newImageHeight = self.currentImageSize.height * ((self.currentNewHeight - (self.currentTextureEndY - self.currentTextureStartY)) + 1);
return CGSizeMake(self.currentImageSize.width, newImageHeight);
}
#pragma mark - Custom Accessor
- (void)setTmpFrameBuffer:(GLuint)tmpFrameBuffer {
if (_tmpFrameBuffer) {
glDeleteFramebuffers(1, &_tmpFrameBuffer);
}
_tmpFrameBuffer = tmpFrameBuffer;
}
#pragma mark - GLKViewDelegate
- (void)glkView:(GLKView *)view drawInRect:(CGRect)rect {
//1.准备绘制GLBaseEffect
[self.baseEffect prepareToDraw];
//2.清空缓存区;
glClear(GL_COLOR_BUFFER_BIT);
//3. 准备绘制数据-顶点数据
[self.vertexAttribArrayBuffer prepareToDrawWithAttrib:GLKVertexAttribPosition
numberOfCoordinates:3
attribOffset:offsetof(SenceVertex, positionCoord)
shouldEnable:YES];
//4. 准备绘制数据-纹理坐标数据
[self.vertexAttribArrayBuffer prepareToDrawWithAttrib:GLKVertexAttribTexCoord0
numberOfCoordinates:2
attribOffset:offsetof(SenceVertex, textureCoord)
shouldEnable:YES];
//5. 开始绘制;
[self.vertexAttribArrayBuffer drawArrayWithMode:GL_TRIANGLE_STRIP
startVertexIndex:0
numberOfVertices:kVerticesCount];
}
@end
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