GL_COMPRESSED_RGBA給出了加擾輸出

Question

我將fbo渲染到紋理，並且紋理完美地顯示出來。但是，當我通過以下函數（使用GL_COMPRESSED_RGBA）運行紋理時，函數返回的textureresult被加擾。我正在使用最新版本的LWJGL。

public static int burnToTexture(int textureId) { 
    // Create fbo for texture 

    fboId = glGenFramebuffersEXT();  
    fboTextureId = glGenTextures();           

    glBindTexture(GL_TEXTURE_2D, 0); 
    glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, fboId);      

    glBindTexture(GL_TEXTURE_2D, fboTextureId);        
    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);     
    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);    
    glTexImage2D(GL_TEXTURE_2D, 0, GL_COMPRESSED_RGBA, SAVE_WIDTH, SAVE_HEIGHT, 0,GL_RGBA, GL_INT, (java.nio.ByteBuffer) null); 
    glFramebufferTexture2DEXT(GL_FRAMEBUFFER_EXT,GL_COLOR_ATTACHMENT0_EXT,GL_TEXTURE_2D, fboTextureId, 0); 

    glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, 0); 
    // Render texture to fbo 
    glPushAttrib(GL_ALL_ATTRIB_BITS); 

    glBindTexture(GL_TEXTURE_2D, 0); 
    glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, fboId);  

    glMatrixMode (GL_MODELVIEW); 
    glLoadIdentity(); 
    glViewport(0,0,SAVE_WIDTH,SAVE_HEIGHT); 
    glMatrixMode(GL_PROJECTION); 
    gluOrtho2D(0, SAVE_WIDTH, 0, SAVE_HEIGHT); 
    glLoadIdentity(); 
    glDisable(GL_DEPTH_TEST); 
    glClearColor(1.0f, 1.0f, 0.0f, 0.0f); 
    glClear (GL_COLOR_BUFFER_BIT); 
    glEnable(GL_TEXTURE_2D); 
    glActiveTextureARB(GL_TEXTURE0_ARB); 

    glBindTexture(GL_TEXTURE_2D, textureId); 
    glBegin (GL_QUADS); 
    glTexCoord2f(0.0f, 0.0f); 
    glVertex2i (-1, -1); 
    glTexCoord2f(1.0f, 0.0f); 
    glVertex2i (1, -1); 
    glTexCoord2f(1.0f, 1.0f); 
    glVertex2i (1, 1); 
    glTexCoord2f(0.0f, 1.0f); 
    glVertex2i (-1, 1); 
    glEnd();   

    glDisable(GL_TEXTURE_2D); 

    glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, 0); 

    glPopAttrib(); 

    // Destroy fbo 
    glDeleteFramebuffersEXT(fboId); 

    return fboTextureId; 
} 

Answer 1

Compressed image formats是not color renderable。而且，顧名思義，您無法渲染到使用非顏色可呈現格式的紋理。