我一直在研究这个问题，但仍未得出结论。有些实例使用纹理作为其渲染目标，有些人使用渲染缓冲区，还有一些人同时使用两者！
例如，只使用纹理：
// Create the gbuffer textures
glGenTextures(ARRAY_SIZE_IN_ELEMENTS(m_textures), m_textures);
glGenTextures(1, &m_depthTexture);
for (unsigned int i = 0 ; i < ARRAY_SIZE_IN_ELEMENTS(m_textures) ; i++) {
glBindTexture(GL_TEXTURE_2D, m_textures[i]);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB32F, WindowWidth, WindowHeight, 0, GL_RGB, GL_FLOAT, NULL);
glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0 + i, GL_TEXTURE_2D, m_textures[i], 0);
}
both:
glGenRenderbuffersEXT ( 1, &m_diffuseRT );
glBindRenderbufferEXT ( GL_RENDERBUFFER_EXT, m_diffuseRT );
glRenderbufferStorageEXT ( GL_RENDERBUFFER_EXT, GL_RGBA, m_width, m_height );
glFramebufferRenderbufferEXT ( GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT, GL_RENDERBUFFER_EXT, m_diffuseRT );
glGenTextures ( 1, &m_diffuseTexture );
glBindTexture ( GL_TEXTURE_2D, m_diffuseTexture );
glTexImage2D ( GL_TEXTURE_2D, 0, GL_RGBA, m_width, m_height, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL );
glTexParameteri ( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR );
glTexParameteri ( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR );
glTexParameteri ( GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE );
glTexParameteri ( GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE );
// Attach the texture to the FBO
glFramebufferTexture2DEXT ( GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT, GL_TEXTURE_2D, m_diffuseTexture, 0 );
有什么不同？创建纹理、渲染缓冲区，然后将一个分配给另一个有什么意义？当您成功地为纹理提供图像时，它已经分配了内存，那么为什么需要将其绑定到渲染缓冲区？
为什么要使用纹理或渲染缓冲区？有什么优点？
我读到过，无法从渲染缓冲区读取数据，只能从纹理中读取。那么它有什么用处呢？
编辑： 因此，我当前的GBuffer代码如下：
enum class GBufferTextureType
{
Depth = 0,
Position,
Diffuse,
Normal,
TexCoord
};
. . .
glGenFramebuffers ( 1, &OpenGLID );
if ( Graphics::GraphicsBackend->CheckError() == false )
{
Delete();
return false;
}
glBindFramebuffer ( GL_FRAMEBUFFER, OpenGLID );
if ( Graphics::GraphicsBackend->CheckError() == false )
{
Delete();
return false;
}
uint32_t TextureGLIDs[5];
glGenTextures ( 5, TextureGLIDs );
if ( Graphics::GraphicsBackend->CheckError() == false )
{
Delete();
return false;
}
// Create the depth texture
glBindTexture ( GL_TEXTURE_2D, TextureGLIDs[ ( int ) GBufferTextureType::Depth] );
glTexImage2D ( GL_TEXTURE_2D, 0, GL_DEPTH_COMPONENT32F, In_Dimensions.x, In_Dimensions.y, 0, GL_DEPTH_COMPONENT, GL_FLOAT, NULL );
glFramebufferTexture2D ( GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D, TextureGLIDs[ ( int ) GBufferTextureType::Depth], 0 );
// Create the color textures
for ( unsigned cont = 1; cont < 5; ++cont )
{
glBindTexture ( GL_TEXTURE_2D, TextureGLIDs[cont] );
glTexImage2D ( GL_TEXTURE_2D, 0, GL_RGB32F, In_Dimensions.x, In_Dimensions.y, 0, GL_RGB, GL_FLOAT, NULL );
glFramebufferTexture2D ( GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0 + cont, GL_TEXTURE_2D, TextureGLIDs[cont], 0 );
}
// Specify draw buffers
GLenum DrawBuffers[4];
for ( unsigned cont = 0; cont < 4; ++cont )
DrawBuffers[cont] = GL_COLOR_ATTACHMENT0 + cont;
glDrawBuffers ( 4, DrawBuffers );
if ( Graphics::GraphicsBackend->CheckError() == false )
{
Delete();
return false;
}
GLenum Status = glCheckFramebufferStatus ( GL_FRAMEBUFFER );
if ( Status != GL_FRAMEBUFFER_COMPLETE )
{
Delete();
return false;
}
Dimensions = In_Dimensions;
// Unbind
glBindFramebuffer ( GL_FRAMEBUFFER, 0 );
这是正确的方法吗？我还需要编写对应的着色器...