OpenGL ES 3.0之顶点缓冲

所谓顶点缓冲就是直接将顶点数据存储在gpu的一段缓冲区，不需要从cpu拷贝到gpu。提高了程序的运行效率。操作步骤1.创建顶点缓冲对象GLuint vertexBufferID;2.分配空间glGenBuffers（1, &vertexBufferID）;3.绑定当前顶点缓冲对象glBindBuffer（GL_ARRAY_BUFFER, vertexBufferID）;4.初始化缓冲区数据glBufferData（GL_ARRAY_BUFFER, sizeof（vertices）, vertices, GL_STATIC_DRAW）;5.启用顶点属性数组glEnableVertexAttribArray（GLKVertexAttribPosition）;6.使用顶点数据进行渲染glVertexAttribPointer（
GLKVertexAttribPosition,
3,
GL_FLOAT,
GL_FALSE,
sizeof（SceneVertex）,
NULL）;7.绘制 glDrawArrays（GL_TRIANGLES, 0,3）;下面赋全部代码@interface OpenGLESViewController : GLKViewController
{
GLuint vertexBufferID;
}@property （strong, nonatomic） GLKBaseEffect *baseEffect;@end #import "OpenGLESViewController.h"@implementation OpenGLESViewController@synthesize baseEffect;/////////////////////////////////////////////////////////////////
// This data type is used to store information for each vertex
typedef struct {
GLKVector3 positionCoords;
}
SceneVertex;// Define vertex data for a triangle to use in example
static const SceneVertex vertices[] =
{
{{-0.5f, -0.5f, 0.0}}, // lower left corner
{{ 0.5f, -0.5f, 0.0}}, // lower right corner
{{-0.5f, 0.5f, 0.0}} // upper left corner
};
/////////////////////////////////////////////////////////////////
// Called when the view controller"s view is loaded
// Perform initialization before the view is asked to draw
- （void）viewDidLoad
{
[super viewDidLoad];

// Verify the type of view created automatically by the
// Interface Builder storyboard
GLKView *view = （GLKView *）self.view;
NSAssert（[view isKindOfClass:[GLKView class]],
@"View controller"s view is not a GLKView"）;

// Create an OpenGL ES 2.0 context and provide it to the
// view
view.context = [[EAGLContext alloc]
initWithAPI:kEAGLRenderingAPIOpenGLES2];

// Make the new context current
[EAGLContext setCurrentContext:view.context];

// Create a base effect that provides standard OpenGL ES 2.0
// Shading Language programs and set constants to be used for
// all subsequent rendering
self.baseEffect = [[GLKBaseEffect alloc] init];
self.baseEffect.useConstantColor = GL_TRUE;
self.baseEffect.constantColor = GLKVector4Make（
1.0f, // Red
1.0f, // Green
1.0f, // Blue
1.0f）;// Alpha

// Set the background color stored in the current context
glClearColor（0.0f, 0.0f, 0.0f, 1.0f）; // background color

// Generate, bind, and initialize contents of a buffer to be
// stored in GPU memory
glGenBuffers（1, // STEP 1
&vertexBufferID）;
glBindBuffer（GL_ARRAY_BUFFER, // STEP 2
vertexBufferID）;
glBufferData（ // STEP 3
GL_ARRAY_BUFFER, // Initialize buffer contents
sizeof（vertices）, // Number of bytes to copy
vertices, // Address of bytes to copy
GL_STATIC_DRAW）; // Hint: cache in GPU memory
}
/////////////////////////////////////////////////////////////////
// GLKView delegate method: Called by the view controller"s view
// whenever Cocoa Touch asks the view controller"s view to
// draw itself. （In this case, render into a frame buffer that
// shares memory with a Core Animation Layer）
- （void）glkView:（GLKView *）view drawInRect:（CGRect）rect
{
[self.baseEffect prepareToDraw];

// Clear Frame Buffer （erase previous drawing）
glClear（GL_COLOR_BUFFER_BIT）;

// Enable use of positions from bound vertex buffer
glEnableVertexAttribArray（ // STEP 4
GLKVertexAttribPosition）;

glVertexAttribPointer（ // STEP 5
GLKVertexAttribPosition,
3, // three components per vertex
GL_FLOAT, // data is floating point
GL_FALSE, // no fixed point scaling
sizeof（SceneVertex）, // no gaps in data
NULL）; // NULL tells GPU to start at
// beginning of bound buffer

// Draw triangles using the first three vertices in the
// currently bound vertex buffer
glDrawArrays（GL_TRIANGLES, // STEP 6
0, // Start with first vertex in currently bound buffer
3）; // Use three vertices from currently bound buffer
}
/////////////////////////////////////////////////////////////////
// Called when the view controller"s view has been unloaded
// Perform clean-up that is possible when you know the view
// controller"s view won"t be asked to draw again soon.
- （void）viewDidUnload
{
[super viewDidUnload];

// Make the view"s context current
GLKView *view = （GLKView *）self.view;
[EAGLContext setCurrentContext:view.context];

// Delete buffers that aren"t needed when view is unloaded
if （0 ！= vertexBufferID）
{
glDeleteBuffers （1, // STEP 7
&vertexBufferID）;
vertexBufferID = 0;
}

// Stop using the context created in -viewDidLoad
（（GLKView *）self.view）.context = nil;
[EAGLContext setCurrentContext:nil];
}@endOpenGL编程指南（原书第7版）中文扫描版PDF 下载 http://www.linuxidc.com/Linux/2012-08/67925.htm-------------------------------------分割线-------------------------------------OpenGL 渲染篇 http://www.linuxidc.com/Linux/2011-10/45756.htmUbuntu 13.04 安装 OpenGL http://www.linuxidc.com/Linux/2013-05/84815.htmOpenGL三维球体数据生成与绘制【附源码】 http://www.linuxidc.com/Linux/2013-04/83235.htmUbuntu下OpenGL编程基础解析 http://www.linuxidc.com/Linux/2013-03/81675.htm如何在Ubuntu使用eclipse for c++配置OpenGL http://www.linuxidc.com/Linux/2012-11/74191.htm《OpenGL超级宝典》学习笔记 http://www.linuxidc.com/Linux/2013-10/91414.htm本文永久更新链接地址：http://www.linuxidc.com/Linux/2015-11/124806.htm