/game-ui-solution/OGRE-1.7.2/RenderSystems/GLES/src/OgreGLESFBORenderTexture.cpp

/*

-----------------------------------------------------------------------------

This source file is part of OGRE

    (Object-oriented Graphics Rendering Engine)

For the latest info, see http://www.ogre3d.org/



Copyright (c) 2000-2009 Torus Knot Software Ltd



Permission is hereby granted, free of charge, to any person obtaining a copy

of this software and associated documentation files (the "Software"), to deal

in the Software without restriction, including without limitation the rights

to use, copy, modify, merge, publish, distribute, sublicense, and/or sell

copies of the Software, and to permit persons to whom the Software is

furnished to do so, subject to the following conditions:



The above copyright notice and this permission notice shall be included in

all copies or substantial portions of the Software.



THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE

AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,

OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN

THE SOFTWARE.

-----------------------------------------------------------------------------

*/



#include "OgreGLESFBORenderTexture.h"

#include "OgreGLESPixelFormat.h"

#include "OgreLogManager.h"

#include "OgreRoot.h"

#include "OgreGLESHardwarePixelBuffer.h"

#include "OgreGLESFBOMultiRenderTarget.h"



namespace Ogre {



//-----------------------------------------------------------------------------    

    GLESFBORenderTexture::GLESFBORenderTexture(GLESFBOManager *manager, const String &name,

        const GLESSurfaceDesc &target, bool writeGamma, uint fsaa):

        GLESRenderTexture(name, target, writeGamma, fsaa),

        mFB(manager, fsaa)

    {

        // Bind target to surface 0 and initialise

        mFB.bindSurface(0, target);

        GL_CHECK_ERROR;

        // Get attributes

        mWidth = mFB.getWidth();

        mHeight = mFB.getHeight();

    }



    void GLESFBORenderTexture::getCustomAttribute(const String& name, void* pData)

    {

        if(name=="FBO")

        {

            *static_cast<GLESFrameBufferObject **>(pData) = &mFB;

        }

    }



	void GLESFBORenderTexture::swapBuffers(bool waitForVSync)

	{

		mFB.swapBuffers();

	}

   

/// Size of probe texture

#define PROBE_SIZE 16



/// Stencil and depth formats to be tried

static const GLenum stencilFormats[] =

{

    GL_NONE,                    // No stencil

    GL_STENCIL_INDEX8_OES

};

static const size_t stencilBits[] =

{

    0, 8

};

#define STENCILFORMAT_COUNT (sizeof(stencilFormats)/sizeof(GLenum))



static const GLenum depthFormats[] =

{

    GL_NONE,

    GL_DEPTH_COMPONENT16_OES,

    GL_DEPTH_COMPONENT24_OES,   // Prefer 24 bit depth

    GL_DEPTH24_STENCIL8_OES     // packed depth / stencil

};

static const size_t depthBits[] =

{

    0,16,24,24

};

#define DEPTHFORMAT_COUNT (sizeof(depthFormats)/sizeof(GLenum))



	GLESFBOManager::GLESFBOManager() 

		: mTempFBO(0)

    {

        detectFBOFormats();

        

        glGenFramebuffersOES(1, &mTempFBO);

        GL_CHECK_ERROR;

    }



	GLESFBOManager::~GLESFBOManager()

	{

		if(!mRenderBufferMap.empty())

		{

			LogManager::getSingleton().logMessage("GL ES: Warning! GLESFBOManager destructor called, but not all renderbuffers were released.");

		}

        

        glDeleteFramebuffersOES(1, &mTempFBO);      

        GL_CHECK_ERROR;

	}



    /** Try a certain FBO format, and return the status. Also sets mDepthRB and mStencilRB.

        @returns true    if this combo is supported

                 false   if this combo is not supported

    */

    GLuint GLESFBOManager::_tryFormat(GLenum depthFormat, GLenum stencilFormat)

    {

        GLuint status, depthRB = 0, stencilRB = 0;



        if(depthFormat != GL_NONE)

        {

            /// Generate depth renderbuffer

            glGenRenderbuffersOES(1, &depthRB);



            /// Bind it to FBO

            glBindRenderbufferOES(GL_RENDERBUFFER_OES, depthRB);

            

            /// Allocate storage for depth buffer

            glRenderbufferStorageOES(GL_RENDERBUFFER_OES, depthFormat,

                                PROBE_SIZE, PROBE_SIZE);

            

            /// Attach depth

            glFramebufferRenderbufferOES(GL_FRAMEBUFFER_OES, GL_DEPTH_ATTACHMENT_OES,

                                    GL_RENDERBUFFER_OES, depthRB);

        }



        // Stencil buffers aren't available on iPhone

        if(stencilFormat != GL_NONE)

        {

            /// Generate stencil renderbuffer

            glGenRenderbuffersOES(1, &stencilRB);

            

            /// Bind it to FBO

            glBindRenderbufferOES(GL_RENDERBUFFER_OES, stencilRB);



            /// Allocate storage for stencil buffer

            glRenderbufferStorageOES(GL_RENDERBUFFER_OES, stencilFormat,

                                PROBE_SIZE, PROBE_SIZE); 



            /// Attach stencil

            glFramebufferRenderbufferOES(GL_FRAMEBUFFER_OES, GL_STENCIL_ATTACHMENT_OES,

                            GL_RENDERBUFFER_OES, stencilRB);

        }



        status = glCheckFramebufferStatusOES(GL_FRAMEBUFFER_OES);



        /// If status is negative, clean up

        // Detach and destroy

        glFramebufferRenderbufferOES(GL_FRAMEBUFFER_OES, GL_DEPTH_ATTACHMENT_OES, GL_RENDERBUFFER_OES, 0);



        glFramebufferRenderbufferOES(GL_FRAMEBUFFER_OES, GL_STENCIL_ATTACHMENT_OES, GL_RENDERBUFFER_OES, 0);



        if (depthRB)

            glDeleteRenderbuffersOES(1, &depthRB);



        if (stencilRB)

            glDeleteRenderbuffersOES(1, &stencilRB);

        

        return status == GL_FRAMEBUFFER_COMPLETE_OES;

    }

    

    /** Try a certain packed depth/stencil format, and return the status.

        @returns true    if this combo is supported

                 false   if this combo is not supported

    */

    bool GLESFBOManager::_tryPackedFormat(GLenum packedFormat)

    {

        GLuint packedRB;



        /// Generate renderbuffer

        glGenRenderbuffersOES(1, &packedRB);



        /// Bind it to FBO

        glBindRenderbufferOES(GL_RENDERBUFFER_OES, packedRB);



        /// Allocate storage for buffer

        glRenderbufferStorageOES(GL_RENDERBUFFER_OES, packedFormat, PROBE_SIZE, PROBE_SIZE);



        /// Attach depth

        glFramebufferRenderbufferOES(GL_FRAMEBUFFER_OES, GL_DEPTH_ATTACHMENT_OES,

            GL_RENDERBUFFER_OES, packedRB);



        /// Attach stencil

        glFramebufferRenderbufferOES(GL_FRAMEBUFFER_OES, GL_STENCIL_ATTACHMENT_OES,

            GL_RENDERBUFFER_OES, packedRB);



        GLuint status = glCheckFramebufferStatusOES(GL_FRAMEBUFFER_OES);



        /// Detach and destroy

        glFramebufferRenderbufferOES(GL_FRAMEBUFFER_OES, GL_DEPTH_ATTACHMENT_OES, GL_RENDERBUFFER_OES, 0);

        glFramebufferRenderbufferOES(GL_FRAMEBUFFER_OES, GL_STENCIL_ATTACHMENT_OES, GL_RENDERBUFFER_OES, 0);

        glDeleteRenderbuffersOES(1, &packedRB);



        return status == GL_FRAMEBUFFER_COMPLETE_OES;

    }



    /** Detect which internal formats are allowed as RTT

        Also detect what combinations of stencil and depth are allowed with this internal

        format.

    */

    void GLESFBOManager::detectFBOFormats()

    {

        // Try all formats, and report which ones work as target

        GLuint fb, tid;

        GLenum target = GL_TEXTURE_2D;



        for(size_t x=0; x<PF_COUNT; ++x)

        {

            mProps[x].valid = false;



			// Fetch GL format token

			GLenum fmt = GLESPixelUtil::getGLInternalFormat((PixelFormat)x);

            if(fmt == GL_NONE && x!=0)

                continue;



			// No test for compressed formats

			if(PixelUtil::isCompressed((PixelFormat)x))

				continue;



            // Create and attach framebuffer

            glGenFramebuffersOES(1, &fb);

            glBindFramebufferOES(GL_FRAMEBUFFER_OES, fb);

            if (fmt!=GL_NONE)

            {

				// Create and attach texture

				glGenTextures(1, &tid);

				glBindTexture(target, tid);

				

                // Set some default parameters

                glTexParameteri(target, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_NEAREST);

                glTexParameteri(target, GL_TEXTURE_MAG_FILTER, GL_NEAREST);

                glTexParameteri(target, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);

                glTexParameteri(target, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);

                            

				glTexImage2D(target, 0, fmt, PROBE_SIZE, PROBE_SIZE, 0, fmt, GL_UNSIGNED_BYTE, 0);

				glFramebufferTexture2DOES(GL_FRAMEBUFFER_OES, GL_COLOR_ATTACHMENT0_OES,

                                target, tid, 0);

            }



            // Check status

            GLuint status = glCheckFramebufferStatusOES(GL_FRAMEBUFFER_OES);



			// Ignore status in case of fmt==GL_NONE, because no implementation will accept

			// a buffer without *any* attachment. Buffers with only stencil and depth attachment

			// might still be supported, so we must continue probing.

            if(fmt == GL_NONE || status == GL_FRAMEBUFFER_COMPLETE_OES)

            {

                mProps[x].valid = true;

				StringUtil::StrStreamType str;

				str << "FBO " << PixelUtil::getFormatName((PixelFormat)x) 

					<< " depth/stencil support: ";



                // For each depth/stencil formats

                for (size_t depth = 0; depth < DEPTHFORMAT_COUNT; ++depth)

                {

                    if (depthFormats[depth] != GL_DEPTH24_STENCIL8_OES)

                    {

                        // General depth/stencil combination



                        for (size_t stencil = 0; stencil < STENCILFORMAT_COUNT; ++stencil)

                        {

                            //StringUtil::StrStreamType l;

                            //l << "Trying " << PixelUtil::getFormatName((PixelFormat)x) 

                            //	<< " D" << depthBits[depth] 

                            //	<< "S" << stencilBits[stencil];

                            //LogManager::getSingleton().logMessage(l.str());



                            if (_tryFormat(depthFormats[depth], stencilFormats[stencil]))

                            {

                                /// Add mode to allowed modes

                                str << "D" << depthBits[depth] << "S" << stencilBits[stencil] << " ";

                                FormatProperties::Mode mode;

                                mode.depth = depth;

                                mode.stencil = stencil;

                                mProps[x].modes.push_back(mode);

                            }

                        }

                    }

                    else

                    {

                        // Packed depth/stencil format

                        if (_tryPackedFormat(depthFormats[depth]))

                        {

                            /// Add mode to allowed modes

                            str << "Packed-D" << depthBits[depth] << "S" << 8 << " ";

                            FormatProperties::Mode mode;

                            mode.depth = depth;

                            mode.stencil = 0;   // unuse

                            mProps[x].modes.push_back(mode);

                        }

                    }

                }

                LogManager::getSingleton().logMessage(str.str());

            }



            // Delete texture and framebuffer

            glBindFramebufferOES(GL_FRAMEBUFFER_OES, 0);

            glDeleteFramebuffersOES(1, &fb);

			

            if (fmt!=GL_NONE)

                glDeleteTextures(1, &tid);

        }



		String fmtstring;

        for(size_t x=0; x<PF_COUNT; ++x)

        {

            if(mProps[x].valid)

                fmtstring += PixelUtil::getFormatName((PixelFormat)x)+" ";

        }

        LogManager::getSingleton().logMessage("[GLES] : Valid FBO targets " + fmtstring);

    }



    void GLESFBOManager::getBestDepthStencil(GLenum internalFormat, GLenum *depthFormat, GLenum *stencilFormat)

    {

        const FormatProperties &props = mProps[internalFormat];

        /// Decide what stencil and depth formats to use

        /// [best supported for internal format]

        size_t bestmode=0;

        int bestscore=-1;

        for(size_t mode=0; mode<props.modes.size(); mode++)

        {

            int desirability = 0;

            /// Find most desirable mode

            /// desirability == 0            if no depth, no stencil

            /// desirability == 1000...2000  if no depth, stencil

            /// desirability == 2000...3000  if depth, no stencil

            /// desirability == 3000+        if depth and stencil

            /// beyond this, the total numer of bits (stencil+depth) is maximised

            if(props.modes[mode].stencil)

                desirability += 1000;

            if(props.modes[mode].depth)

                desirability += 2000;

            if(depthBits[props.modes[mode].depth]==24) // Prefer 24 bit for now

                desirability += 500;

			if(depthFormats[props.modes[mode].depth]==GL_DEPTH24_STENCIL8_OES) // Prefer 24/8 packed 

				desirability += 5000;

            desirability += stencilBits[props.modes[mode].stencil] + depthBits[props.modes[mode].depth];

            

            if(desirability>bestscore)

            {

                bestscore = desirability;

                bestmode = mode;

            }

        }

        *depthFormat = depthFormats[props.modes[bestmode].depth];

        *stencilFormat = stencilFormats[props.modes[bestmode].stencil];

    }



    GLESFBORenderTexture *GLESFBOManager::createRenderTexture(const String &name, 

		const GLESSurfaceDesc &target, bool writeGamma, uint fsaa)

    {

        GLESFBORenderTexture *retval = OGRE_NEW GLESFBORenderTexture(this, name, target, writeGamma, fsaa);

        return retval;

    }

	MultiRenderTarget *GLESFBOManager::createMultiRenderTarget(const String & name)

	{

		return OGRE_NEW GLESFBOMultiRenderTarget(this, name);

	}



    void GLESFBOManager::bind(RenderTarget *target)

    {

        /// Check if the render target is in the rendertarget->FBO map

        GLESFrameBufferObject *fbo = 0;

        target->getCustomAttribute("FBO", &fbo);

        if(fbo)

            fbo->bind();

        else

            // Old style context (window/pbuffer) or copying render texture

#if OGRE_PLATFORM == OGRE_PLATFORM_IPHONE

            // The screen buffer is 1 on iPhone

            glBindFramebufferOES(GL_FRAMEBUFFER_OES, 1);

#else

            glBindFramebufferOES(GL_FRAMEBUFFER_OES, 0);

#endif

        GL_CHECK_ERROR;

    }

    

    GLESSurfaceDesc GLESFBOManager::requestRenderBuffer(GLenum format, size_t width, size_t height, uint fsaa)

    {

        GLESSurfaceDesc retval;

        retval.buffer = 0; // Return 0 buffer if GL_NONE is requested

        if(format != GL_NONE)

        {

            RBFormat key(format, width, height, fsaa);

            RenderBufferMap::iterator it = mRenderBufferMap.find(key);

            if(it != mRenderBufferMap.end())

            {

                retval.buffer = it->second.buffer;

                retval.zoffset = 0;

				retval.numSamples = fsaa;

                // Increase refcount

                ++it->second.refcount;

            }

            else

            {

                // New one

                GLESRenderBuffer *rb = OGRE_NEW GLESRenderBuffer(format, width, height, fsaa);

                mRenderBufferMap[key] = RBRef(rb);

                retval.buffer = rb;

                retval.zoffset = 0;

				retval.numSamples = fsaa;

            }

        }

//        std::cerr << "Requested renderbuffer with format " << std::hex << format << std::dec << " of " << width << "x" << height << " :" << retval.buffer << std::endl;

        return retval;

    }

    //-----------------------------------------------------------------------

    void GLESFBOManager::requestRenderBuffer(const GLESSurfaceDesc &surface)

    {

        if(surface.buffer == 0)

            return;

        RBFormat key(surface.buffer->getGLFormat(), surface.buffer->getWidth(), surface.buffer->getHeight(), surface.numSamples);

        RenderBufferMap::iterator it = mRenderBufferMap.find(key);

        assert(it != mRenderBufferMap.end());

        if (it != mRenderBufferMap.end())   // Just in case

        {

            assert(it->second.buffer == surface.buffer);

            // Increase refcount

            ++it->second.refcount;

        }

    }

    //-----------------------------------------------------------------------

    void GLESFBOManager::releaseRenderBuffer(const GLESSurfaceDesc &surface)

    {

        if(surface.buffer == 0)

            return;

        RBFormat key(surface.buffer->getGLFormat(), surface.buffer->getWidth(), surface.buffer->getHeight(), surface.numSamples);

        RenderBufferMap::iterator it = mRenderBufferMap.find(key);

        if(it != mRenderBufferMap.end())

		{

			// Decrease refcount

			--it->second.refcount;

			if(it->second.refcount==0)

			{

				// If refcount reaches zero, delete buffer and remove from map

				OGRE_DELETE it->second.buffer;

				mRenderBufferMap.erase(it);

				//std::cerr << "Destroyed renderbuffer of format " << std::hex << key.format << std::dec

				//        << " of " << key.width << "x" << key.height << std::endl;

			}

		}

    }

}