axmol/cocos2dx/misc_nodes/CCRenderTexture.cpp

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#include "CCRenderTexture.h"
#include "CCDirector.h"
#include "platform/platform.h"
#include "CCXUIImage.h"
#include <GLES/glext.h>

namespace cocos2d { 

	// implementation CCRenderTexture
	CCSprite * CCRenderTexture::getSprite()
	{
		return m_pSprite;
	}
	void CCRenderTexture::setSprite(CCSprite* var)
	{
		m_pSprite = var;
	}

	CCRenderTexture * CCRenderTexture::renderTextureWithWidthAndHeight(int width, int height)
	{
		CCRenderTexture *pRet = new CCRenderTexture();

		if(pRet && pRet->initWithWidthAndHeight(width,height))
		{
			pRet->autorelease();
			return pRet;
		}
		CCX_SAFE_DELETE(pRet)
		return NULL;
	}
	bool CCRenderTexture::initWithWidthAndHeight(int width, int height)
	{
		glGetIntegerv(GL_FRAMEBUFFER_BINDING_OES, &m_nOldFBO);
		CCTexture2DPixelFormat format = kCCTexture2DPixelFormat_RGBA8888;  
		// textures must be power of two squared
		int pow = 8;
		while (pow < width || pow < height)
		{
			pow*=2;
		}
		void *data = malloc((int)(pow * pow * 4));
		memset(data, 0, (int)(pow * pow * 4));
		m_pTexture = new CCTexture2D();
		m_pTexture->initWithData(data, format, pow, pow, CGSizeMake((float)width, (float)height));
		free( data );
		// generate FBO
		glGenFramebuffersOES(1, &m_uFBO);
		glBindFramebufferOES(GL_FRAMEBUFFER_OES, m_uFBO);
		// associate texture with FBO
		glFramebufferTexture2DOES(GL_FRAMEBUFFER_OES, GL_COLOR_ATTACHMENT0_OES, GL_TEXTURE_2D, m_pTexture->getName(), 0);

		// check if it worked (probably worth doing :) )
		GLuint status = glCheckFramebufferStatusOES(GL_FRAMEBUFFER_OES);
		if (status != GL_FRAMEBUFFER_COMPLETE_OES)
		{
			NSAssert(0, "Render Texture : Could not attach texture to framebuffer")
			CCX_SAFE_DELETE(m_pTexture);
			return false;
		}
		m_pSprite = CCSprite::spriteWithTexture(m_pTexture);
		m_pTexture->release();
		m_pSprite->setScaleY(-1);
		this->addChild(m_pSprite);
		glBindFramebufferOES(GL_FRAMEBUFFER_OES, m_nOldFBO);
		return true;
	}
	CCRenderTexture::~CCRenderTexture()
	{
		glDeleteFramebuffersOES(1, &m_uFBO);
	}
	void CCRenderTexture::begin()
	{
		CC_DISABLE_DEFAULT_GL_STATES();
		// Save the current matrix
		glPushMatrix();

		CGSize textureSize = m_pTexture->getContentSize();

		// Calculate the adjustment ratios based on the old and new projections
		CGRect frame = CCDirector::getSharedDirector()->getOpenGLView()->getFrame();
		float widthRatio = frame.size.width / textureSize.width;
		float heightRatio = frame.size.height / textureSize.height;

		// Adjust the orthographic propjection and viewport
		glOrthof((float)-1.0 / widthRatio,  (float)1.0 / widthRatio, (float)-1.0 / heightRatio, (float)1.0 / heightRatio, -1,1);
		glViewport(0, 0, (GLsizei)textureSize.width, (GLsizei)textureSize.height);

		glGetIntegerv(GL_FRAMEBUFFER_BINDING_OES, &m_nOldFBO);
		glBindFramebufferOES(GL_FRAMEBUFFER_OES, m_uFBO);//Will direct drawing to the frame buffer created above

		CC_ENABLE_DEFAULT_GL_STATES();	
	}
	void CCRenderTexture::end()
	{
		glBindFramebufferOES(GL_FRAMEBUFFER_OES, m_nOldFBO);
		// Restore the original matrix and viewport
		glPopMatrix();
		CGRect frame = CCDirector::getSharedDirector()->getOpenGLView()->getFrame();
		glViewport(0, 0, (GLsizei)frame.size.width, (GLsizei)frame.size.height);

		glColorMask(TRUE, TRUE, TRUE, TRUE);
	}
	void CCRenderTexture::clear(float r, float g, float b, float a)
	{
		this->begin();
		glClearColor(r, g, b, a);
		glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
		glColorMask(TRUE, TRUE, TRUE, FALSE);
		this->end();
	}
	bool CCRenderTexture::saveBuffer(const char *name)
	{
		return this->saveBuffer(name, kImageFormatJPG);
	}
	bool CCRenderTexture::saveBuffer(const char *name, int format)
	{
		bool bRet = false;
		UIImage *myImage = this->getUIImageFromBuffer();
		if (myImage)
		{
			bRet = myImage->save(name, format);
			delete myImage;
		}
		return bRet;
	}

	/* get buffer as UIImage */
	UIImage * CCRenderTexture::getUIImageFromBuffer()
	{
 		int tx = (int)m_pTexture->getContentSize().width;
 		int ty = (int)m_pTexture->getContentSize().height;
 
 		CCXBitmapDC *pBitmap = new CCXBitmapDC(tx, ty);
 		void *pBuffer = pBitmap->getBuffer();
 
 		this->begin();
 		glReadPixels(0,0,tx,ty,GL_RGBA,GL_UNSIGNED_BYTE, pBuffer);
 		this->end();
 
 		UIImage *pRet = new UIImage();
 		pRet->initWithBuffer(tx, ty, (unsigned char*)pBuffer);
 		return pRet;
	}

} // namespace cocos2d