macvideo.cpp

英特尔&#174 线程构建模块（英特尔&#174 TBB）是一个屡获殊荣的 C++ 运行时库

    {
        GetPort (&portSave);    // save current port
        SetPort ((GrafPtr) GetWindowPort (window)); // set port to the current window
        // set parameters for Carbon SetupGL
        pWindowInfo->glInfo.fAcceleratedMust = false; // must renderer be accelerated?
        pWindowInfo->glInfo.VRAM = 0 * 1048576; // minimum VRAM (if not zero this is always required)
        pWindowInfo->glInfo.textureRAM = 0 * 1048576; // minimum texture RAM (if not zero this is always required)
           pWindowInfo->glInfo.fDraggable = true; // is this a draggable window
        pWindowInfo->glInfo.fmt = 0; // output pixel format
        
        i = 0; // first attribute in array
        pWindowInfo->glInfo.aglAttributes [i++] = AGL_RGBA; // RGB + Alpha pixels
        pWindowInfo->glInfo.aglAttributes [i++] = AGL_DOUBLEBUFFER; // doble buffered context
        pWindowInfo->glInfo.aglAttributes [i++] = AGL_ACCELERATED; // require hardware acceleration
        pWindowInfo->glInfo.aglAttributes [i++] = AGL_NO_RECOVERY; // 10.0.4 has problems with the GL (disregards UNPACK_ROW_LENGTH) resulting from using no recovery
                                                                   // normally we would use no recovery to ensure the minimum pixel size textures are stored by GL.
        pWindowInfo->glInfo.aglAttributes [i++] = AGL_NONE; // end parameter list
        BuildGLonWindow (window, &(pWindowInfo->aglContext), &(pWindowInfo->glInfo), NULL); // build opengl context for our window
        if (!pWindowInfo->aglContext) // if could not create context
            DestroyGLFromWindow (&pWindowInfo->aglContext, &pWindowInfo->glInfo); // ensure context is destroyed correctly
        else // we have a valid context
        {
            GLint swap = 0; // swap interval (i.e., VBL sync) setting 1 = sync, 0 = no sync
            Rect rectPort; // window port rectangle
            long width = pWindowInfo->imageWidth, height = pWindowInfo->imageHeight; // image width and height
            GDHandle device; // GDevice to find the constrain the window to
            Rect deviceRect, availRect, rect; // rect of device which window is on (mostly, area wise at least). avialable area for window (minus dock and menu if req), working rect

            GetWindowGreatestAreaDevice (window, kWindowContentRgn, &device, &deviceRect); // find device the window is mostly on
            GetAvailableWindowPositioningBounds (device, &availRect); //  get the geretest available area for te windoew (mminus doc and menu if applicable)
            if (width > (availRect.right - availRect.left)) // adjust window width if it is greater than available area (orginally set to image width, see above)
                width = (availRect.right - availRect.left);
            if (height > (availRect.bottom - availRect.top)) // adjust window height if it is greater than available area (orginally set to image width, see above)
                height = (availRect.bottom - availRect.top);
            SizeWindow (window, (short) width, (short) height, true); // size the window to new width and height
            ConstrainWindowToScreen(window, kWindowStructureRgn, kWindowConstrainMayResize, NULL, &rect); // ensure window structure region is on the screen
            GetWindowPortBounds (window, &rectPort); // get port rect for viewport reset

            aglSetCurrentContext (pWindowInfo->aglContext); // set our GL context to this one
            aglUpdateContext (pWindowInfo->aglContext); // update the context to account for the resize
            InvalWindowRect (window, &rectPort); // inval the entire window to ensure we get a redraw
            glViewport (0, 0, rectPort.right - rectPort.left, rectPort.bottom - rectPort.top); // reset viewport to entier window area

            aglSetInteger (pWindowInfo->aglContext, AGL_SWAP_INTERVAL, &swap); // set swap interval to account for vbl syncing or not
            
            // set correct texture target // if building on 10.0 or 9 this will be undefined
        #ifdef GL_TEXTURE_RECTANGLE_EXT
            if (pWindowInfo->fNPOTTextures)
                textureTarget = GL_TEXTURE_RECTANGLE_EXT;
        #endif
            
            // Set texture mapping parameters
            glEnable (textureTarget); // enable texturing
                
            glClearColor(0.0f, 0.0f, 0.0f, 1.0f); // set clear color buffer to dark gray
            glClear (GL_COLOR_BUFFER_BIT); // clear just to color buffer
            aglSwapBuffers (pWindowInfo->aglContext); // swap the cleared buffer to front
    
            //GetFNum ("\pMonaco", &fNum); // get font number for named font
            //pWindowInfo->fontList = BuildFontGL (pWindowInfo->aglContext, fNum, normal, 9); // build display list for fonts for this context (see aglString for more info)
            
            // if we can use texture rectangle // if building on 10.0 or 9 this will be undefined
        #ifdef GL_TEXTURE_RECTANGLE_EXT
            if (pWindowInfo->fNPOTTextures)
                glEnable(GL_TEXTURE_RECTANGLE_EXT);
        #endif
            if (pWindowInfo->fAGPTexturing)
                glTextureRangeAPPLE(textureTarget, pWindowInfo->textureHeight * pWindowInfo->textureWidth * (pWindowInfo->imageDepth >> 3), pWindowInfo->pImageBuffer);
            glPixelStorei (GL_UNPACK_ROW_LENGTH, pWindowInfo->textureWidth); // set image width in groups (pixels), accounts for border this ensures proper image alignment row to row
            // get number of textures x and y
                // extract the number of horiz. textures needed to tile image
            pWindowInfo->textureX = GetTextureNumFromTextureDim (pWindowInfo->textureWidth, pWindowInfo->maxTextureSize, pWindowInfo->fOverlapTextures, pWindowInfo->fNPOTTextures); 
                // extract the number of horiz. textures needed to tile image
            pWindowInfo->textureY = GetTextureNumFromTextureDim (pWindowInfo->textureHeight, pWindowInfo->maxTextureSize, pWindowInfo->fOverlapTextures, pWindowInfo->fNPOTTextures); 
            pWindowInfo->pTextureName = (GLuint *) NewPtrClear ((long) sizeof (GLuint) * pWindowInfo->textureX * pWindowInfo->textureY); // allocate storage for texture name lists
            glGenTextures (pWindowInfo->textureX * pWindowInfo->textureY, pWindowInfo->pTextureName); // generate textures names need to support tiling
            {
                long x, y, k = 0, offsetY, offsetX = 0, currWidth, currHeight; // texture iterators, texture name iterator, image offsets for tiling, current texture width and height
                for (x = 0; x < pWindowInfo->textureX; x++) // for all horizontal textures
                {
                    currWidth = GetNextTextureSize (pWindowInfo->textureWidth - offsetX, pWindowInfo->maxTextureSize, pWindowInfo->fNPOTTextures); // use remaining to determine next texture size 
                                                                                                                    // (basically greatest power of 2 which fits into remaining space)
                    offsetY = 0; // reset vertical offest for every column
                    for (y = 0; y < pWindowInfo->textureY; y++) // for all vertical textures
                    {
                        // buffer pointer is at base + rows * row size + columns
                        unsigned char * pBuffer = pWindowInfo->pImageBuffer + 
                                                   offsetY * pWindowInfo->textureWidth * (pWindowInfo->imageDepth >> 3) + 
                                                   offsetX * (pWindowInfo->imageDepth >> 3);
                        currHeight = GetNextTextureSize (pWindowInfo->textureHeight - offsetY, pWindowInfo->maxTextureSize, pWindowInfo->fNPOTTextures); // use remaining to determine next texture size
                        glBindTexture (textureTarget, pWindowInfo->pTextureName[k++]);
                        if (pWindowInfo->fAGPTexturing) {
                            glTexParameterf (textureTarget, GL_TEXTURE_PRIORITY, 0.0f); // AGP texturing
                            glTexParameteri (textureTarget, GL_TEXTURE_STORAGE_HINT_APPLE, GL_STORAGE_SHARED_APPLE);
                        }
                        else
                            glTexParameterf (textureTarget, GL_TEXTURE_PRIORITY, 1.0f);
                            
                    #ifdef GL_UNPACK_CLIENT_STORAGE_APPLE
                        if (pWindowInfo->fClientTextures)
                            glPixelStorei (GL_UNPACK_CLIENT_STORAGE_APPLE, 1);
                        else
                            glPixelStorei (GL_UNPACK_CLIENT_STORAGE_APPLE, 0);
                    #endif

                        glTexParameteri (textureTarget, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
                        glTexParameteri (textureTarget, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
                        glTexParameteri (textureTarget, GL_TEXTURE_WRAP_S, gpOpenGLCaps->edgeClampParam);
                        glTexParameteri (textureTarget, GL_TEXTURE_WRAP_T, gpOpenGLCaps->edgeClampParam);
                        glReportError (); // report any errors so far
                        glTexImage2D (textureTarget, 0, GL_RGBA, currWidth, currHeight, 0, 
                                      GL_BGRA_EXT, pWindowInfo->imageDepth == 32 ? GL_UNSIGNED_INT_8_8_8_8_REV : GL_UNSIGNED_SHORT_1_5_5_5_REV, 
                                      pBuffer); // texture with current width and height at pBuffer location in image buffer with image size as GL_UNPACK_ROW_LENGTH
                        glReportError (); // report any errors
                        offsetY += currHeight - 2 * pWindowInfo->fOverlapTextures; // offset in for the amount of texture used, 
                                                                                       //  since we are overlapping the effective texture used is 2 texels less than texture width
                    }
                    offsetX += currWidth - 2 * pWindowInfo->fOverlapTextures; // offset in for the amount of texture used, 
                                                                              //  since we are overlapping the effective texture used is 2 texels less than texture width
                }
            }
            if (false == pWindowInfo->fClientTextures) // MUST preserve the buffer if texturing from client memory
            {
                DisposePtr ((Ptr) pWindowInfo->pImageBuffer); // or image buffer
                pWindowInfo->pImageBuffer = NULL;
            }
        }
        SetPort (portSave); //reset port
    }
    return noErr; // we done
}

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

// Handle updating context for window moves and resizing

OSStatus ResizeMoveGLWindow (WindowRef window)
{
    OSStatus err = noErr; // no errors to start
    Rect rectPort; // new port rect
    pRecImage pWindowInfo = (pRecImage) GetWRefCon (window); // get GL info;
    if (window && pWindowInfo) // if we have a window
    {
        GetWindowPortBounds (window, &rectPort);
        pWindowInfo->zoomX = (float) (rectPort.right - rectPort.left) / (float) pWindowInfo->imageWidth;
        pWindowInfo->zoomY = (float) (rectPort.bottom - rectPort.top) / (float) pWindowInfo->imageHeight;

        if (!aglUpdateContext (pWindowInfo->aglContext)) // update the context to ensure gl knows about the move or resize
               aglReportError (); // report any error with update context
        if (noErr != err)
            ReportErrorNum ("ResizeMoveGLWindow error with InvalWindowRect on window: ", err);  // should not get erro here, but who knows
        err = InvalWindowRect (window, &rectPort);
    }
    else
        err = paramErr; // bad window
    return err; // return any error 
}

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

// main GL drawing routine, should be valid window passed in (will setupGL if require).  Draw image

void DrawGL (WindowRef window)
{
    Rect rectPort; // rectangle for port
    pRecImage pWindowInfo; // the gl info for the target window 
    long width, height; // width and height or the port and the row of the raster position
    long effectiveTextureMod = 0; // texture size modification (inset) to account for borders
    long x, y, k = 0, offsetY, offsetX = 0, currTextureWidth, currTextureHeight;
    GLenum textureTarget = GL_TEXTURE_2D;
    
    if (NULL == window) // if we do not have a window
        return; // drop out
    pWindowInfo = (pRecImage) GetWRefCon (window); // get the gl info for the window
    if (NULL == pWindowInfo) // if this is non-existant
        return; // then drop out
    if (NULL == pWindowInfo->aglContext) // try to buld the context if we don't have one (safety check)
        BuildGLForWindow (window);
    if (NULL == pWindowInfo->aglContext) // if we still don't have one then drop out
        return;
        
    if (pWindowInfo->fOverlapTextures)
        effectiveTextureMod = 2; // if we overlap then we need to inset the textures passed to the drawing code
    // set texture target
#ifdef GL_TEXTURE_RECTANGLE_EXT
    if (pWindowInfo->fNPOTTextures)
        textureTarget = GL_TEXTURE_RECTANGLE_EXT;
#endif

    aglSetCurrentContext (pWindowInfo->aglContext); // ensaure the context we are working with is set to current
    aglUpdateContext (pWindowInfo->aglContext); // ensaure the context we are working with is set to current

    GetWindowPortBounds (window, &rectPort); // get the current port (window) bounds
    width = rectPort.right - rectPort.left; // find width
    height = rectPort.bottom - rectPort.top; // and height
    glViewport (0, 0, width, height); // set the viewport to cover entire window
    
    glMatrixMode (GL_PROJECTION); // set projection matrix
    glLoadIdentity (); // to indetity
    glMatrixMode (GL_MODELVIEW); // set modelview matrix
    glLoadIdentity (); // to identity
    glReportError (); // report any GL errors so far
    
    // set the model view matrix for an orthographic view scaled to one screen pixel equal image pixel (independent of image zoom)
    glScalef (2.0f / width, -2.0f /  height, 1.0f); // scale to port per pixel scale
    //glTranslatef (pWindowInfo->centerX, pWindowInfo->centerY, 0.0f); // translate for image movement
    //glRotatef (0.0f, 0.0f, 0.0f, 1.0f); // ratate matrix for image rotation
    glReportError (); // report any GL errors
    
    glClear (GL_COLOR_BUFFER_BIT); // clear the color buffer before drawing

    // draw image
    glEnable (textureTarget); // enable texturing
    glColor3f (1.0f, 1.0f, 1.0f); // white polygons
    // offset x and y are used to draw the polygon and need to represent the texture effective edges (without borders)
    // so walk the texture size images adjusting for each border
    for (x = 0; x < pWindowInfo->textureX; x++) // for all horizontal textures
    {
        // use remaining to determine next texture size
        currTextureWidth = GetNextTextureSize (pWindowInfo->textureWidth - offsetX, pWindowInfo->maxTextureSize, pWindowInfo->fNPOTTextures) - effectiveTextureMod; // current effective texture width for drawing
        offsetY = 0; // start at top
        for (y = 0; y < pWindowInfo->textureY; y++) // for a complete column
        {
            // use remaining to determine next texture size
            currTextureHeight = GetNextTextureSize (pWindowInfo->textureHeight - offsetY, pWindowInfo->maxTextureSize, pWindowInfo->fNPOTTextures) - effectiveTextureMod; // effective texture height for drawing
            glBindTexture(textureTarget, pWindowInfo->pTextureName[k++]); // work through textures in same order as stored, setting each texture name as current in turn
            if (!pWindowInfo->fAGPTexturing)
                glTexSubImage2D(textureTarget, 0, 0, 0, currTextureWidth, currTextureHeight, GL_BGRA, pWindowInfo->imageDepth == 32 ? GL_UNSIGNED_INT_8_8_8_8_REV : GL_UNSIGNED_SHORT_1_5_5_5_REV, pWindowInfo->pImageBuffer);
            glReportError (); // report any errors
            {
                float endX = pWindowInfo->fTileTextures ? currTextureWidth + offsetX : pWindowInfo->imageWidth;
                float endY = pWindowInfo->fTileTextures ? currTextureHeight + offsetY : pWindowInfo->imageHeight;
                float startXDraw = (offsetX - pWindowInfo->imageWidth * 0.5f) * pWindowInfo->zoomX; // left edge of poly: offset is in image local coordinates convert to world coordinates
                float endXDraw = (endX - pWindowInfo->imageWidth * 0.5f) * pWindowInfo->zoomX; // right edge of poly: offset is in image local coordinates convert to world coordinates
                float startYDraw = (offsetY - pWindowInfo->imageHeight * 0.5f) * pWindowInfo->zoomY; // top edge of poly: offset is in image local coordinates convert to world coordinates
                float endYDraw = (endY - pWindowInfo->imageHeight * 0.5f) * pWindowInfo->zoomY; // bottom edge of poly: offset is in image local coordinates convert to world coordinates
                float texOverlap =  pWindowInfo->fOverlapTextures ? 1.0f : 0.0f; // size of texture overlap, switch based on whether we are using overlap or not
                float startXTexCoord = texOverlap / (currTextureWidth + 2.0f * texOverlap); // texture right edge coordinate (stepped in one pixel for border if required)
                float endXTexCoord = 1.0f - startXTexCoord; // texture left edge coordinate (stepped in one pixel for border if required)
                float startYTexCoord = texOverlap / (currTextureHeight + 2.0f * texOverlap); // texture top edge coordinate (stepped in one pixel for border if required)
                float endYTexCoord = 1.0f - startYTexCoord; // texture bottom edge coordinate (stepped in one pixel for border if required)
                if (pWindowInfo->fNPOTTextures)
                {
                    startXTexCoord = texOverlap; // texture right edge coordinate (stepped in one pixel for border if required)
                    endXTexCoord = currTextureWidth + texOverlap; // texture left edge coordinate (stepped in one pixel for border if required)
                    startYTexCoord = texOverlap; // texture top edge coordinate (stepped in one pixel for border if required)
                    endYTexCoord = currTextureHeight + texOverlap; // texture bottom edge coordinate (stepped in one pixel for border if required)
                }
                if (endX > (pWindowInfo->imageWidth + 0.5)) // handle odd image sizes, (+0.5 is to ensure there is no fp resolution problem in comparing two fp numbers)
                {
                    endXDraw = (pWindowInfo->imageWidth * 0.5f) * pWindowInfo->zoomX; // end should never be past end of image, so set it there
                    if (pWindowInfo->fNPOTTextures)
                        endXTexCoord -= 1.0f;
                    else
                        endXTexCoord = 1.0f -  2.0f * startXTexCoord; // for the last texture in odd size images there are two texels of padding so step in 2
                }
                if (endY > (pWindowInfo->imageHeight + 0.5f)) // handle odd image sizes, (+0.5 is to ensure there is no fp resolution problem in comparing two fp numbers)
                {
                    endYDraw = (pWindowInfo->imageHeight * 0.5f) * pWindowInfo->zoomY; // end should never be past end of image, so set it there
                    if (pWindowInfo->fNPOTTextures)
                        endYTexCoord -= 1.0f;
                    else
                        endYTexCoord = 1.0f -  2.0f * startYTexCoord; // for the last texture in odd size images there are two texels of padding so step in 2
                }