Question

我的渲染到纹理过程有问题。当我使用width = height = 512渲染场景时，它几乎没有错误，但纹理和场景越小，得到的错误就越多。错误是纹理的区域是黑色的，没有任何意义。

以下是一些截图

512 * 512：http://www.ld-host.de/uploads/images/d9452fa0ba28494830fd96f0f15b9eba.png 128 * 128：http://www.ld-host.de/uploads/images/a39c141282a622f086d4a96b070a56a3.png

这是我的代码如何渲染到纹理并稍后使用纹理

    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT)
    glMatrixMode(GL_MODELVIEW)
    glLoadIdentity()
    gluLookAt(0,0,200,0,0,-1,0,1,0)


    self.fbos = glGenFramebuffersEXT(1)
    glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, self.fbos)
    self.depthbuffers = (glGenRenderbuffersEXT(1)
    glBindRenderbufferEXT(GL_RENDERBUFFER_EXT, self.depthbuffers)
    glRenderbufferStorageEXT(GL_RENDERBUFFER_EXT, GL_DEPTH_COMPONENT, width, height)
    glFramebufferRenderbufferEXT(GL_FRAMEBUFFER_EXT, GL_DEPTH_ATTACHMENT_EXT, GL_RENDERBUFFER_EXT, self.depthbuffers)       

    self.textures = glGenTextures(1)
    glBindTexture(GL_TEXTURE_2D, self.textures)
    glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER, GL_LINEAR)
    glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER, GL_LINEAR)
    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8,  width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, None);
    glFramebufferTexture2DEXT(GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT,  GL_TEXTURE_2D, self.textures, 0);
    glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, self.fbos);

    glEnable(GL_CLIP_PLANE0)
    glEnable(GL_CLIP_PLANE1)
    glClipPlane(GL_CLIP_PLANE0, (0,0,1,-1 * self.start + self.diff))       
    glClipPlane(GL_CLIP_PLANE1, (0,0,-1,self.start))   

    # render the mesh
    glTranslatef(-64,-64,-64)
    glEnableClientState(GL_VERTEX_ARRAY) # Enable something in OpenGL 
    glEnableClientState(GL_COLOR_ARRAY) # Enable something in OpenGL
    glBindBuffer(GL_ARRAY_BUFFER,self.vbo[1]) 
    glColorPointer(3,GL_FLOAT,0,None) # Tell OpenGL that it contains only ColorValues
    #Now the vertex Buffer with positions
    glBindBuffer(GL_ARRAY_BUFFER,self.vbo[0]) 
    glVertexPointer(3,GL_FLOAT,0,None) # Tell OpenGL that it contains the Positions for each Points
    glDrawArrays(GL_TRIANGLES,0,len(self.verts)+len(self.color))    # Merge both

    glDisableClientState(GL_COLOR_ARRAY); 
    glDisableClientState(GL_VERTEX_ARRAY);
    glDisable(GL_CLIP_PLANE0)
    glDisable(GL_CLIP_PLANE1)
    glBindTexture(GL_TEXTURE_2D,0)
    glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, 0); 

    #Plane for showing texture
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT)
    glMatrixMode(GL_MODELVIEW)
    glLoadIdentity()
    gluLookAt(0,0,1,0,0,0,0,1,0)
    glClearColor(1,1,1,0)

    glEnable(GL_TEXTURE_2D)

    glBindTexture(GL_TEXTURE_2D, self.textures)
    glBegin(GL_QUADS)
    glNormal3f(0.0, 1.0, 0.0)
    glTexCoord2f(0.0, 0.0)
    glVertex3f(-1, 1, -1)
    glTexCoord2f(1.0, 0.0)
    glVertex3f(1, 1, -1)
    glTexCoord2f(1.0, 1.0)
    glVertex3f(1, -1, -1)
    glTexCoord2f(0.0, 1.0)
    glVertex3f(-1, -1, -1)
    glEnd();
    glDisable(GL_TEXTURE_2D)

    pygame.display.flip()

如何为较小的纹理获得更好的质量？网格没有洞，但纹理有时会有。

Answer 1

我不知道你到底希望看到什么。您正在绘制明显小于像素/样本大小的三角形/立方体/等。因此，并非所有这些都可见。

这是一个标准的别名问题：不会覆盖像素/样本中心的三角形将不可见。这就是光栅化的本质。修复别名的唯一方法是增加您使用的样本数量。您可以以更高的分辨率和缩减比例渲染，也可以使用MSAA或其他实际混叠技术。

渲染到纹理 - 细节层次

1 个答案: