OutputSurface.cc

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#include "OutputSurface.hh"
#include "unreachable.hh"
#include "build-info.hh"

namespace openmsx {

void OutputSurface::lock()
{
        if (isLocked()) return;
        locked = true;
        if (surface && SDL_MUSTLOCK(surface)) {
                // Note: we ignore the return value from SDL_LockSurface()
                SDL_LockSurface(surface);
        }
}

void OutputSurface::unlock()
{
        if (!isLocked()) return;
        locked = false;
        if (surface && SDL_MUSTLOCK(surface)) {
                SDL_UnlockSurface(surface);
        }
}

void OutputSurface::calculateViewPort(gl::ivec2 physSize_)
{
        m_physSize = physSize_;
        gl::vec2 physSize(physSize_);

        gl::vec2 logSize = gl::vec2(getLogicalSize());
        float scale = min_component(physSize / logSize);
        m_viewScale = gl::vec2(scale); // for now always same X and Y scale

        gl::vec2 viewSize = logSize * scale;
        m_viewSize = round(viewSize);

        gl::vec2 viewOffset = (physSize - viewSize) / 2.0f;
        m_viewOffset = round(viewOffset);
}

void OutputSurface::setSDLFormat(const SDL_PixelFormat& format_)
{
        format = format_;
#if HAVE_32BPP
        // SDL sets an alpha channel only for GL modes. We want an alpha channel
        // for all 32bpp output surfaces, so we add one ourselves if necessary.
        if (format.BytesPerPixel == 4 && format.Amask == 0) {
                unsigned rgbMask = format.Rmask | format.Gmask | format.Bmask;
                if ((rgbMask & 0x000000FF) == 0) {
                        format.Amask  = 0x000000FF;
                        format.Ashift = 0;
                        format.Aloss  = 0;
                } else if ((rgbMask & 0xFF000000) == 0) {
                        format.Amask  = 0xFF000000;
                        format.Ashift = 24;
                        format.Aloss  = 0;
                } else {
                        UNREACHABLE;
                }
        }
#endif
}

void OutputSurface::setBufferPtr(char* data_, unsigned pitch_)
{
        data = data_;
        pitch = pitch_;
}

void OutputSurface::flushFrameBuffer()
{
}

void  OutputSurface::clearScreen()
{
}

} // namespace openmsx