llrendertarget.h

Go to the documentation of this file.

#ifndef LL_LLRENDERTARGET_H
#define LL_LLRENDERTARGET_H

#include "llgl.h"

/*
 SAMPLE USAGE:

        LLRenderTarget target;

        ...

        //allocate a 256x256 RGBA render target with depth buffer
        target.allocate(256,256,GL_RGBA,TRUE);

        //render to contents of offscreen buffer
        target.bindTarget();
        target.clear();
        ... <issue drawing commands> ...
        target.flush();

        ...

        //use target as a texture
        target.bindTexture();
        ... <issue drawing commands> ...

*/


class LLRenderTarget
{
public:
        //whether or not to use FBO implementation
        static BOOL sUseFBO; 

        LLRenderTarget();
        ~LLRenderTarget();

        //allocate resources for rendering
        //must be called before use
        //multiple calls will release previously allocated resources
        void allocate(U32 resx, U32 resy, U32 color_fmt, BOOL depth, U32 usage = GL_TEXTURE_2D, BOOL use_fbo = FALSE);

        //allocate a depth texture
        void allocateDepth();

        //free any allocated resources
        //safe to call redundantly
        void release();

        //bind target for rendering
        //applies appropriate viewport
        void bindTarget();

        //unbind target for rendering
        static void unbindTarget();
        
        //clear render targer, clears depth buffer if present,
        //uses scissor rect if in copy-to-texture mode
        void clear();
        
        //get applied viewport
        void getViewport(S32* viewport);

        //get X resolution
        U32 getWidth() const { return mResX; }

        //get Y resolution
        U32 getHeight() const { return mResY; }

        //bind results of render for sampling
        void bindTexture();

        //bind results of render for sampling depth buffer
        void bindDepth();

        //flush rendering operations
        //must be called when rendering is complete
        //should be used 1:1 with bindTarget 
        // call bindTarget once, do all your rendering, call flush once
        // if fetch_depth is TRUE, every effort will be made to copy the depth buffer into 
        // the current depth texture.  A depth texture will be allocated if needed.
        void flush(BOOL fetch_depth = FALSE);

        //Returns TRUE if target is ready to be rendered into.
        //That is, if the target has been allocated with at least
        //one renderable attachment (i.e. color buffer, depth buffer).
        BOOL isComplete() const;

private:
        U32 mResX;
        U32 mResY;
        U32 mTex;
        U32 mFBO;
        U32 mDepth;
        U32 mStencil;
        BOOL mUseDepth;
        BOOL mRenderDepth;
        U32 mUsage;
        
};

#endif

---