source: trunk/src/opengl/qglpixelbuffer_mac.mm@ 454

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#include "qglpixelbuffer.h"
#include "qglpixelbuffer_p.h"

#ifndef QT_MAC_USE_COCOA
#include <AGL/agl.h>
#endif

#include <qimage.h>
#include <private/qgl_p.h>
#include <qdebug.h>

QT_BEGIN_NAMESPACE

#ifndef GL_TEXTURE_RECTANGLE_EXT
#define GL_TEXTURE_RECTANGLE_EXT 0x84F5
#endif

static int nearest_gl_texture_size(int v)
{
    int n = 0, last = 0;
    for (int s = 0; s < 32; ++s) {
        if (((v>>s) & 1) == 1) {
            ++n;
            last = s;
        }
    }
    if (n > 1)
        return 1 << (last+1);
    return 1 << last;
}

bool QGLPixelBufferPrivate::init(const QSize &size, const QGLFormat &f, QGLWidget *shareWidget)
{
#ifdef QT_MAC_USE_COCOA
    Q_Q(QGLPixelBuffer);
    // create a dummy context
    QGLContext context(f, q);
    context.create(shareWidget ? shareWidget->context() : 0);

    if (context.isSharing())
        share_ctx = shareWidget->context()->d_func()->cx;

    // steal the NSOpenGLContext and update the format
    ctx = context.d_func()->cx;
    context.d_func()->cx = 0;
    // d->cx will be set to ctx later in
    // QGLPixelBufferPrivate::common_init, so we need to retain it:
    [static_cast<NSOpenGLContext *>(ctx) retain];

    format = context.format();

    GLenum target = GL_TEXTURE_2D;

    if ((QGLExtensions::glExtensions & QGLExtensions::TextureRectangle)
        && (size.width() != nearest_gl_texture_size(size.width())
            || size.height() != nearest_gl_texture_size(size.height())))
    {
        target = GL_TEXTURE_RECTANGLE_EXT;
    }

    pbuf = [[NSOpenGLPixelBuffer alloc] initWithTextureTarget:target
                                        textureInternalFormat:GL_RGBA
                                        textureMaxMipMapLevel:0
                                                  pixelsWide:size.width()
                                                  pixelsHigh:size.height()];
    if (!pbuf) {
        qWarning("QGLPixelBuffer: Cannot create a pbuffer");
        return false;
    }

    [static_cast<NSOpenGLContext *>(ctx) setPixelBuffer:static_cast<NSOpenGLPixelBuffer *>(pbuf)
                                            cubeMapFace:0
                                            mipMapLevel:0
                                   currentVirtualScreen:0];
    return true;
#else
    GLint attribs[40], i=0;
    attribs[i++] = AGL_RGBA;
    attribs[i++] = AGL_BUFFER_SIZE;
    attribs[i++] = 32;
    attribs[i++] = AGL_LEVEL;
    attribs[i++] = f.plane();
    if (f.redBufferSize() != -1) {
        attribs[i++] = AGL_RED_SIZE;
        attribs[i++] = f.redBufferSize();
    }
    if (f.greenBufferSize() != -1) {
        attribs[i++] = AGL_GREEN_SIZE;
        attribs[i++] = f.greenBufferSize();
    }
    if (f.blueBufferSize() != -1) {
        attribs[i++] = AGL_BLUE_SIZE;
        attribs[i++] = f.blueBufferSize();
    }
    if (f.stereo())
        attribs[i++] = AGL_STEREO;
    if (f.alpha()) {
        attribs[i++] = AGL_ALPHA_SIZE;
        attribs[i++] = f.alphaBufferSize() == -1 ? 8 : f.alphaBufferSize();