[cocos2d-x]对CCSprite进行高斯模糊

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蓬莱仙羽 2023-07-27 14:26:56 博主文章分类：Cocos2d-X

摘要 cocos2d-x 2.2.1 中没有直接用于模糊精灵的类，但是在TestCpp里面的ShaderTest实现了高斯模糊。于是直接搬过来用就行了。

你可以从下面的目录找到示例的源代码：

cocos2d-x-2.2.1\samples\Cpp\TestCpp\Classes\ShaderTest

SpriteBlur类用于实现高斯模糊，但并没有定义在ShaderTest.h中，打开ShaderTest.cpp，大概在488行有这个类的定义和实现：

	// ShaderBlur
02
 
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class SpriteBlur : public CCSprite
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{
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public:
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    ~SpriteBlur();
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    void setBlurSize(float f);
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    bool initWithTexture(CCTexture2D* texture, const CCRect&  rect);
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    void draw();
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    void initProgram();
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    void listenBackToForeground(CCObject *obj);
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    static SpriteBlur* create(const char *pszFileName);
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    CCPoint blur_;
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    GLfloat    sub_[4];
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    GLuint    blurLocation;
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    GLuint    subLocation;
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};

实现：

SpriteBlur::~SpriteBlur()
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{
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    CCNotificationCenter::sharedNotificationCenter()->removeObserver(this, EVENT_COME_TO_FOREGROUND);
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}
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SpriteBlur* SpriteBlur::create(const char *pszFileName)
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{
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    SpriteBlur* pRet = new SpriteBlur();
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    if (pRet && pRet->initWithFile(pszFileName))
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    {
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        pRet->autorelease();
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    }
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    else
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    {
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        CC_SAFE_DELETE(pRet);
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    }
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    return pRet;
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}
020
 
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void SpriteBlur::listenBackToForeground(CCObject *obj)
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{
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    setShaderProgram(NULL);
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    initProgram();
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}
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bool SpriteBlur::initWithTexture(CCTexture2D* texture, const CCRect& rect)
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{
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    if( CCSprite::initWithTexture(texture, rect) ) 
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    {
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        CCNotificationCenter::sharedNotificationCenter()->addObserver(this,
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                                                                      callfuncO_selector(SpriteBlur::listenBackToForeground),
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                                                                      EVENT_COME_TO_FOREGROUND,
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                                                                      NULL);
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        CCSize s = getTexture()->getContentSizeInPixels();
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        blur_ = ccp(1/s.width, 1/s.height);
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        sub_[0] = sub_[1] = sub_[2] = sub_[3] = 0;
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        this->initProgram();
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        return true;
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    }
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    return false;
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}
048
 
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void SpriteBlur::initProgram()
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{
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    GLchar * fragSource = (GLchar*) CCString::createWithContentsOfFile(
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                                CCFileUtils::sharedFileUtils()->fullPathForFilename("Shaders/example_Blur.fsh").c_str())->getCString();
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    CCGLProgram* pProgram = new CCGLProgram();
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    pProgram->initWithVertexShaderByteArray(ccPositionTextureColor_vert, fragSource);
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    setShaderProgram(pProgram);
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    pProgram->release();
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    CHECK_GL_ERROR_DEBUG();
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    getShaderProgram()->addAttribute(kCCAttributeNamePosition, kCCVertexAttrib_Position);
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    getShaderProgram()->addAttribute(kCCAttributeNameColor, kCCVertexAttrib_Color);
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    getShaderProgram()->addAttribute(kCCAttributeNameTexCoord, kCCVertexAttrib_TexCoords);
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    CHECK_GL_ERROR_DEBUG();
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    getShaderProgram()->link();
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    CHECK_GL_ERROR_DEBUG();
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    getShaderProgram()->updateUniforms();
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    CHECK_GL_ERROR_DEBUG();
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    subLocation = glGetUniformLocation( getShaderProgram()->getProgram(), "substract");
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    blurLocation = glGetUniformLocation( getShaderProgram()->getProgram(), "blurSize");
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    CHECK_GL_ERROR_DEBUG();
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}
079
 
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void SpriteBlur::draw()
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{
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    ccGLEnableVertexAttribs(kCCVertexAttribFlag_PosColorTex );
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    ccBlendFunc blend = getBlendFunc();
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    ccGLBlendFunc(blend.src, blend.dst);
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    getShaderProgram()->use();
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    getShaderProgram()->setUniformsForBuiltins();
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    getShaderProgram()->setUniformLocationWith2f(blurLocation, blur_.x, blur_.y);
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    getShaderProgram()->setUniformLocationWith4fv(subLocation, sub_, 1);
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    ccGLBindTexture2D( getTexture()->getName());
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    //
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    // Attributes
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    //
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#define kQuadSize sizeof(m_sQuad.bl)
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    long offset = (long)&m_sQuad;
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    // vertex
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    int diff = offsetof( ccV3F_C4B_T2F, vertices);
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    glVertexAttribPointer(kCCVertexAttrib_Position, 3, GL_FLOAT, GL_FALSE, kQuadSize, (void*) (offset + diff));
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    // texCoods
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    diff = offsetof( ccV3F_C4B_T2F, texCoords);
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    glVertexAttribPointer(kCCVertexAttrib_TexCoords, 2, GL_FLOAT, GL_FALSE, kQuadSize, (void*)(offset + diff));
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    // color
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    diff = offsetof( ccV3F_C4B_T2F, colors);
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    glVertexAttribPointer(kCCVertexAttrib_Color, 4, GL_UNSIGNED_BYTE, GL_TRUE, kQuadSize, (void*)(offset + diff));
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111
 
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    glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
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    CC_INCREMENT_GL_DRAWS(1);
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}
116
 
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void SpriteBlur::setBlurSize(float f)
118
{
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    CCSize s = getTexture()->getContentSizeInPixels();
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    blur_ = ccp(1/s.width, 1/s.height);
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    blur_ = ccpMult(blur_,f);
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}

好了，直接copy到你的program里面，不过有一点需要注意，就是他这个只能用一个文件(图片)create，如果需要用一个Texture初始化(因为有时候需要模糊即时的sprite)，可以稍微改装一下，加一个函数：

static SpriteBlur* createWithTexture(CCTexture2D *pTexture);

实现：

01
SpriteBlur* SpriteBlur::createWithTexture(CCTexture2D *pTexture)
02
{
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    CCAssert(pTexture != NULL, "Invalid texture for sprite");
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    CCRect rect = CCRectZero;
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    rect.size = pTexture->getContentSize();
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    SpriteBlur* pRet = new SpriteBlur();
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    if (pRet && pRet->initWithTexture(pTexture,rect))
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    {
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        pRet->autorelease();
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    }
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    else
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    {
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        CC_SAFE_DELETE(pRet);
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    }
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    return pRet;
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}

用法：

	SpriteBlur *bluredSpr = SpriteBlur::createWithTexture(tex);
2
bluredSpr->setPosition(ccp(sz.width/2,sz.height/2));
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bluredSpr->setBlurSize(0.9f); // 这里稍微设小一点
4
addChild(bluredSpr);

效果：