C++ Extensions3D::supports方法代码示例

GraphicsContext3D::GraphicsContext3D(GraphicsContext3D::Attributes attrs, HostWindow* hostWindow, bool renderDirectlyToHostWindow)
    : m_currentWidth(0)
    , m_currentHeight(0)
    , m_hostWindow(hostWindow)
    , m_context(BlackBerry::Platform::Graphics::createWebGLContext())
    , m_extensions(adoptPtr(new Extensions3DOpenGL(this)))
    , m_attrs(attrs)
    , m_texture(0)
    , m_fbo(0)
    , m_depthStencilBuffer(0)
    , m_boundFBO(0)
    , m_activeTexture(GL_TEXTURE0)
    , m_boundTexture0(0)
    , m_multisampleFBO(0)
    , m_multisampleDepthStencilBuffer(0)
    , m_multisampleColorBuffer(0)
{
    if (!renderDirectlyToHostWindow) {
#if USE(ACCELERATED_COMPOSITING)
        m_compositingLayer = WebGLLayerWebKitThread::create();
#endif
        makeContextCurrent();

        Extensions3D* extensions = getExtensions();
        if (!extensions->supports("GL_IMG_multisampled_render_to_texture"))
            m_attrs.antialias = false;

        // Create a texture to render into.
        ::glGenTextures(1, &m_texture);
        ::glBindTexture(GL_TEXTURE_2D, m_texture);
        ::glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
        ::glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_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);
        ::glBindTexture(GL_TEXTURE_2D, 0);

        // Create an FBO.
        ::glGenFramebuffers(1, &m_fbo);
        ::glBindFramebuffer(GL_FRAMEBUFFER, m_fbo);
        if (m_attrs.stencil || m_attrs.depth)
            ::glGenRenderbuffers(1, &m_depthStencilBuffer);
        m_boundFBO = m_fbo;

#if USE(ACCELERATED_COMPOSITING)
        static_cast<WebGLLayerWebKitThread*>(m_compositingLayer.get())->setWebGLContext(this);
#endif
    }

    // FIXME: If GraphicsContext3D is created with renderDirectlyToHostWindow == true,
    // makeContextCurrent() will make the shared context current.
    makeContextCurrent();

    // FIXME: Do we need to enable GL_VERTEX_PROGRAM_POINT_SIZE with GL ES2? See PR #120141.

    ::glClearColor(0, 0, 0, 0);
}

void GraphicsContext3D::validateAttributes()
{
    validateDepthStencil("GL_OES_packed_depth_stencil");

    if (m_attrs.antialias) {
        Extensions3D* extensions = getExtensions();
        if (!extensions->supports("GL_IMG_multisampled_render_to_texture"))
            m_attrs.antialias = false;
    }
}

// static
bool WebGLDrawBuffers::supported(WebGLRenderingContext* context)
{
#if OS(DARWIN)
    // https://bugs.webkit.org/show_bug.cgi?id=112486
    return false;
#endif
    Extensions3D* extensions = context->graphicsContext3D()->getExtensions();
    return (extensions->supports("GL_EXT_draw_buffers")
        && satisfiesWebGLRequirements(context));
}

bool LayerTextureUpdaterSkPicture::createFrameBuffer()
{
    ASSERT(!m_fbo);
    ASSERT(!m_bufferSize.isEmpty());

    // SKIA only needs color and stencil buffers, not depth buffer.
    // But it is very uncommon for cards to support color + stencil FBO config.
    // The most common config is color + packed-depth-stencil.
    // Instead of iterating through all possible FBO configs, we only try the
    // most common one here.
    // FIXME: Delegate the task of creating frame-buffer to SKIA.
    // It has all necessary code to iterate through all possible configs
    // and choose the one most suitable for its purposes.
    Extensions3D* extensions = context()->getExtensions();
    if (!extensions->supports("GL_OES_packed_depth_stencil"))
        return false;
    extensions->ensureEnabled("GL_OES_packed_depth_stencil");

    // Create and bind a frame-buffer-object.
    m_fbo = context()->createFramebuffer();
    if (!m_fbo)
        return false;
    context()->bindFramebuffer(GraphicsContext3D::FRAMEBUFFER, m_fbo);

    // We just need to create a stencil buffer for FBO.
    // The color buffer (texture) will be provided by tiles.
    // SKIA does not need depth buffer.
    m_depthStencilBuffer = context()->createRenderbuffer();
    if (!m_depthStencilBuffer) {
        deleteFrameBuffer();
        return false;
    }
    context()->bindRenderbuffer(GraphicsContext3D::RENDERBUFFER, m_depthStencilBuffer);
    context()->renderbufferStorage(GraphicsContext3D::RENDERBUFFER, Extensions3D::DEPTH24_STENCIL8, m_bufferSize.width(), m_bufferSize.height());
    context()->framebufferRenderbuffer(GraphicsContext3D::FRAMEBUFFER, GraphicsContext3D::DEPTH_ATTACHMENT, GraphicsContext3D::RENDERBUFFER, m_depthStencilBuffer);
    context()->framebufferRenderbuffer(GraphicsContext3D::FRAMEBUFFER, GraphicsContext3D::STENCIL_ATTACHMENT, GraphicsContext3D::RENDERBUFFER, m_depthStencilBuffer);

    // Create a skia gpu canvas.
    GrContext* skiaContext = m_context->grContext();
    GrPlatformSurfaceDesc targetDesc;
    targetDesc.reset();
    targetDesc.fSurfaceType = kRenderTarget_GrPlatformSurfaceType;
    targetDesc.fRenderTargetFlags = kNone_GrPlatformRenderTargetFlagBit;
    targetDesc.fWidth = m_bufferSize.width();
    targetDesc.fHeight = m_bufferSize.height();
    targetDesc.fConfig = kRGBA_8888_GrPixelConfig;
    targetDesc.fStencilBits = 8;
    targetDesc.fPlatformRenderTarget = m_fbo;
    SkAutoTUnref<GrRenderTarget> target(static_cast<GrRenderTarget*>(skiaContext->createPlatformSurface(targetDesc)));
    SkAutoTUnref<SkDevice> device(new SkGpuDevice(skiaContext, target.get()));
    m_canvas = adoptPtr(new SkCanvas(device.get()));

    context()->bindFramebuffer(GraphicsContext3D::FRAMEBUFFER, 0);
    return true;
}

PassRefPtr<DrawingBuffer> DrawingBuffer::create(GraphicsContext3D* context, const IntSize& size, PreserveDrawingBuffer preserve, AlphaRequirement alpha)
{

#if PLATFORM(JS)
	webkitTrace();
#endif
    Extensions3D* extensions = context->getExtensions();
    bool multisampleSupported = extensions->maySupportMultisampling()
        && extensions->supports("GL_ANGLE_framebuffer_blit")
        && extensions->supports("GL_ANGLE_framebuffer_multisample")
        && extensions->supports("GL_OES_rgb8_rgba8");
    if (multisampleSupported) {
        extensions->ensureEnabled("GL_ANGLE_framebuffer_blit");
        extensions->ensureEnabled("GL_ANGLE_framebuffer_multisample");
        extensions->ensureEnabled("GL_OES_rgb8_rgba8");
    }
    bool packedDepthStencilSupported = extensions->supports("GL_OES_packed_depth_stencil");
    if (packedDepthStencilSupported)
        extensions->ensureEnabled("GL_OES_packed_depth_stencil");
    RefPtr<DrawingBuffer> drawingBuffer = adoptRef(new DrawingBuffer(context, size, multisampleSupported, packedDepthStencilSupported, preserve, alpha));
    return (drawingBuffer->m_context) ? drawingBuffer.release() : 0;
}

void GraphicsContext3D::validateDepthStencil(const char* packedDepthStencilExtension)
{
    Extensions3D* extensions = getExtensions();
    if (m_attrs.stencil) {
        if (extensions->supports(packedDepthStencilExtension)) {
            extensions->ensureEnabled(packedDepthStencilExtension);
            // Force depth if stencil is true.
            m_attrs.depth = true;
        } else
            m_attrs.stencil = false;
    }
    if (m_attrs.antialias) {
        bool isValidVendor = true;
        // Currently in Mac we only turn on antialias if vendor is NVIDIA,
        // or if ATI and on 10.7.2 and above.
        const char* vendor = reinterpret_cast<const char*>(::glGetString(GL_VENDOR));
        if (!vendor || (!std::strstr(vendor, "NVIDIA") && !(std::strstr(vendor, "ATI") && systemAllowsMultisamplingOnATICards())))
            isValidVendor = false;
        if (!isValidVendor || !extensions->supports("GL_ANGLE_framebuffer_multisample") || isGLES2Compliant())
            m_attrs.antialias = false;
        else
            extensions->ensureEnabled("GL_ANGLE_framebuffer_multisample");
    }
}

bool WebGLDrawBuffers::supported(WebGLRenderingContextBase* context)
{
    Extensions3D* extensions = context->graphicsContext3D()->getExtensions();
    return extensions->supports("GL_EXT_draw_buffers")
        && satisfiesWebGLRequirements(context);
}

bool OESTextureFloatLinear::supported(WebGLRenderingContext* context)
{
    Extensions3D* extensions = context->graphicsContext3D()->extensions();
    return extensions->supports("GL_OES_texture_float_linear");
}

bool ANGLEInstancedArrays::supported(WebGLRenderingContext* context)
{
    Extensions3D* extensions = context->graphicsContext3D()->extensions();
    return extensions->supports("GL_ANGLE_instanced_arrays");
}

bool WebGLCompressedTextureATC::supported(WebGLRenderingContext* context)
{
    Extensions3D* extensions = context->graphicsContext3D()->getExtensions();
    return extensions->supports("GL_AMD_compressed_ATC_texture");
}

bool OESStandardDerivatives::supported(WebGLRenderingContext* context)
{
    Extensions3D* extensions = context->graphicsContext3D()->extensions();
    return extensions->supports("GL_OES_standard_derivatives");
}

bool OESElementIndexUint::supported(WebGLRenderingContext* context)
{
    Extensions3D* extensions = context->graphicsContext3D()->getExtensions();
    return extensions->supports("GL_OES_element_index_uint");
}

bool OESVertexArrayObject::supported(WebGLRenderingContext* context)
{
    Extensions3D* extensions = context->graphicsContext3D()->extensions();
    return extensions->supports("GL_OES_vertex_array_object");
}