Method Enable

GTE/Graphics/GL46/GL46DrawTarget.cpp:53–111

}

void GL46DrawTarget::Enable()
{
    // Save the current viewport settings so they can be restored when
    // Disable is called.
    std::array<GLint, 4> intVals{};
    std::array<GLdouble, 2> doubleVals{};
    glGetIntegerv(GL_VIEWPORT, intVals.data());
    glGetDoublev(GL_DEPTH_RANGE, doubleVals.data());
    mSaveViewportX = intVals[0];
    mSaveViewportY = intVals[1];
    mSaveViewportWidth = intVals[2];
    mSaveViewportHeight = intVals[3];
    mSaveViewportNear = doubleVals[0];
    mSaveViewportFar = doubleVals[1];

    // Set viewport according to draw target;
    auto viewportWidth = static_cast<GLsizei>(mTarget->GetWidth());
    auto viewportHeight = static_cast<GLsizei>(mTarget->GetHeight());
    glViewport(0, 0, viewportWidth, viewportHeight);

    // Set depth range to full.
    glDepthRange(0.0, 1.0);

    // Bind the frame buffer.
    glBindFramebuffer(GL_DRAW_FRAMEBUFFER, mFrameBuffer);

    // Attach depth buffer if there is one.
    if (mDSTexture)
    {
        uint32_t format = mDSTexture->GetTexture()->GetFormat();
        GLenum attachment{};
        if (format == DF_D24_UNORM_S8_UINT)
        {
            attachment = GL_DEPTH_STENCIL_ATTACHMENT;
        }
        else  // for now only DF_D24_UNORM_S8_UINT or DF_D32_FLOAT supported
        {
            attachment = GL_DEPTH_ATTACHMENT;
        }
        glFramebufferTexture2D(GL_DRAW_FRAMEBUFFER, attachment, GL_TEXTURE_2D, mDSTexture->GetGLHandle(), 0);
    }

    // Attach each render target.  Build list of attachments to use for
    // drawing to.
    auto const numTargets = mTarget->GetNumTargets();
    std::vector<GLenum> useDrawBuffers(numTargets);
    for (uint32_t i = 0; i < numTargets; ++i)
    {
        auto colorTarget = GL_COLOR_ATTACHMENT0 + i;

        useDrawBuffers[i] = colorTarget;

        auto textureRT = mRTTextures[i];
        glFramebufferTexture2D(GL_DRAW_FRAMEBUFFER, colorTarget, GL_TEXTURE_2D, textureRT->GetGLHandle(), 0);
    }

    // Set which draw buffers to use.
    glDrawBuffers(static_cast<GLsizei>(useDrawBuffers.size()), useDrawBuffers.data());