VisibleSurface.cc

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#include "VisibleSurface.hh"
 
#include "BooleanSetting.hh"
#include "CliComm.hh"
#include "Display.hh"
#include "Event.hh"
#include "EventDistributor.hh"
#include "FileContext.hh"
#include "FloatSetting.hh"
#include "GLContext.hh"
#include "GLSnow.hh"
#include "GLUtil.hh"
#include "Icon.hh"
#include "ImGuiLayer.hh"
#include "InitException.hh"
#include "InputEventGenerator.hh"
#include "MemBuffer.hh"
#include "OffScreenSurface.hh"
#include "OSDGUILayer.hh"
#include "PNG.hh"
#include "RenderSettings.hh"
#include "VideoSystem.hh"
 
#include "narrow.hh"
#include "outer.hh"
#include "small_buffer.hh"
#include "view.hh"
 
#include "build-info.hh"
 
#include <imgui.h>
#include <imgui_impl_sdl2.h>
#include <imgui_impl_opengl3.h>
 
#include <bit>
#include <cassert>
#include <memory>
 
namespace openmsx {
 
VisibleSurface::VisibleSurface(
                Display& display_,
                RTScheduler& rtScheduler_,
                EventDistributor& eventDistributor_,
                InputEventGenerator& inputEventGenerator_,
                CliComm& cliComm_,
                VideoSystem& videoSystem_)
        : RTSchedulable(rtScheduler_)
        , display(display_)
        , eventDistributor(eventDistributor_)
        , inputEventGenerator(inputEventGenerator_)
        , cliComm(cliComm_)
        , videoSystem(videoSystem_)
{
        auto& renderSettings = display.getRenderSettings();
 
        inputEventGenerator.getGrabInput().attach(*this);
        renderSettings.getPointerHideDelaySetting().attach(*this);
        renderSettings.getFullScreenSetting().attach(*this);
 
        for (auto type : {EventType::MOUSE_MOTION,
                          EventType::MOUSE_BUTTON_DOWN,
                          EventType::MOUSE_BUTTON_UP,
                          EventType::IMGUI_ACTIVE}) {
                eventDistributor.registerEventListener(type, *this);
        }
 
        updateCursor();
        SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);
        SDL_GL_SetAttribute(SDL_GL_DEPTH_SIZE, 0);
        SDL_GL_SetAttribute(SDL_GL_STENCIL_SIZE, 0);
#if OPENGL_VERSION == OPENGL_ES_2_0
        #define VERSION_STRING "openGL ES 2.0"
        const char* glsl_version = "#version 100";
        SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_ES);
        SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 2);
        SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 0);
#elif OPENGL_VERSION == OPENGL_2_1
        #define VERSION_STRING "openGL 2.1"
        const char* glsl_version = "#version 120";
        SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_COMPATIBILITY);
        SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 2);
        SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 1);
#elif OPENGL_VERSION == OPENGL_3_3
        #define VERSION_STRING "openGL 3.3"
        const char* glsl_version = "#version 150";
        SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_CORE);
        SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 3);
        SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 3);
#endif
 
        int flags = SDL_WINDOW_OPENGL;
        //flags |= SDL_RESIZABLE;
        auto size = display.getWindowSize();
        createSurface(size, flags);
        WindowEvent::setMainWindowId(SDL_GetWindowID(window.get()));
 
        glContext = SDL_GL_CreateContext(window.get());
        if (!glContext) {
                throw InitException(
                        "Failed to create " VERSION_STRING " context: ", SDL_GetError());
        }
 
        // Setup ImGui Platform/Renderer backends
        ImGui_ImplSDL2_InitForOpenGL(window.get(), glContext);
        ImGui_ImplOpenGL3_Init(glsl_version);
 
        // From the glew documentation:
        //   GLEW obtains information on the supported extensions from the
        //   graphics driver. Experimental or pre-release drivers, however,
        //   might not report every available extension through the standard
        //   mechanism, in which case GLEW will report it unsupported. To
        //   circumvent this situation, the glewExperimental global switch can
        //   be turned on by setting it to GL_TRUE before calling glewInit(),
        //   which ensures that all extensions with valid entry points will be
        //   exposed.
        // The 'glewinfo' utility also sets this flag before reporting results,
        // so I believe it would cause less confusion to do the same here.
        glewExperimental = GL_TRUE;
 
        // Initialise GLEW library.
        // GLEW fails to initialise on Wayland because it has no GLX, since the
        // one provided by the distros was built to use GLX instead of EGL. We
        // ignore the GLEW_ERROR_NO_GLX_DISPLAY error with this temporary fix
        // until it is fixed by GLEW upstream and released by major distros.
        // See https://github.com/nigels-com/glew/issues/172
        if (GLenum glew_error = glewInit();
            glew_error != GLEW_OK && glew_error != GLEW_ERROR_NO_GLX_DISPLAY) {
                throw InitException(
                        "Failed to init GLEW: ",
                        std::bit_cast<const char*>(glewGetErrorString(glew_error)));
        }
        if (!GLEW_VERSION_2_1) {
                throw InitException(
                        "Need at least OpenGL version " VERSION_STRING);
        }
        gl::context.emplace();
 
        bool fullScreen = renderSettings.getFullScreen();
        setViewPort(size, fullScreen); // set initial values
 
        renderSettings.getVSyncSetting().attach(vSyncObserver);
        // set initial value
        vSyncObserver.update(renderSettings.getVSyncSetting());
 
#if OPENGL_VERSION == OPENGL_3_3
        // We don't (yet/anymore) use VAO, but apparently it's required in openGL 3.3.
        // Luckily this workaround is sufficient: create one global VAO and then don't care anymore.
        GLuint vao;
        glGenVertexArrays(1, &vao);
        glBindVertexArray(vao);
#endif
}
 
VisibleSurface::~VisibleSurface()
{
        auto& renderSettings = display.getRenderSettings();
        renderSettings.getVSyncSetting().detach(vSyncObserver);
 
        ImGui_ImplOpenGL3_Shutdown();
        ImGui_ImplSDL2_Shutdown();
 
        gl::context.reset();
        SDL_GL_DeleteContext(glContext);
 
        // store last known position for when we recreate it
        // the window gets recreated when changing renderers, for instance.
        // Do not store if we're full screen, the location is the top-left
        if (auto pos = getWindowPosition()) {
                display.storeWindowPosition(*pos);
        }
 
        for (auto type : {EventType::IMGUI_ACTIVE,
                          EventType::MOUSE_BUTTON_UP,
                          EventType::MOUSE_BUTTON_DOWN,
                          EventType::MOUSE_MOTION}) {
                eventDistributor.unregisterEventListener(type, *this);
        }
 
        inputEventGenerator.getGrabInput().detach(*this);
        renderSettings.getPointerHideDelaySetting().detach(*this);
        renderSettings.getFullScreenSetting().detach(*this);
}
 
std::optional<gl::ivec2> VisibleSurface::getWindowPosition() const
{
        if (SDL_GetWindowFlags(window.get()) & SDL_WINDOW_FULLSCREEN) return {};
        int x, y;
        SDL_GetWindowPosition(window.get(), &x, &y);
        return gl::ivec2{x, y};
}
 
void VisibleSurface::setWindowPosition(gl::ivec2 pos)
{
        if (SDL_GetWindowFlags(window.get()) & SDL_WINDOW_FULLSCREEN) return;
        SDL_SetWindowPosition(window.get(), pos.x, pos.y);
}
 
// TODO: The video subsystem is not de-initialized on errors.
//       While it would be consistent to do so, doing it in this class is
//       not ideal since the init doesn't happen here.
void VisibleSurface::createSurface(gl::ivec2 size, unsigned flags)
{
        if (getDisplay().getRenderSettings().getFullScreen()) {
                flags |= SDL_WINDOW_FULLSCREEN_DESKTOP;
        }
#ifdef __APPLE__
        // See VisibleSurface::setViewPort() for why only macos (for now).
        flags |= SDL_WINDOW_ALLOW_HIGHDPI;
#endif
 
        assert(!window);
        auto pos = display.retrieveWindowPosition();
        window.reset(SDL_CreateWindow(
                        getDisplay().getWindowTitle().c_str(),
                        pos.x, pos.y,
                        size.x, size.y,
                        flags));
        if (!window) {
                std::string err = SDL_GetError();
                throw InitException("Could not create window: ", err);
        }
 
        updateWindowTitle();
 
        // prefer linear filtering (instead of nearest neighbour)
        SDL_SetHint(SDL_HINT_RENDER_SCALE_QUALITY, "1");
 
        // set icon
        if constexpr (OPENMSX_SET_WINDOW_ICON) {
                SDLSurfacePtr iconSurf;
                // always use 32x32 icon on Windows, for some reason you get badly scaled icons there
#ifndef _WIN32
                try {
                        iconSurf = PNG::load(preferSystemFileContext().resolve("icons/openMSX-logo-256.png"), true);
                } catch (MSXException& e) {
                        getCliComm().printWarning(
                                "Falling back to built in 32x32 icon, because failed to load icon: ",
                                e.getMessage());
#endif
                        PixelOperations pixelOps;
                        iconSurf.reset(SDL_CreateRGBSurfaceFrom(
                                const_cast<char*>(openMSX_icon.pixel_data),
                                narrow<int>(openMSX_icon.width),
                                narrow<int>(openMSX_icon.height),
                                narrow<int>(openMSX_icon.bytes_per_pixel * 8),
                                narrow<int>(openMSX_icon.bytes_per_pixel * openMSX_icon.width),
                                pixelOps.getRmask(),
                                pixelOps.getGmask(),
                                pixelOps.getBmask(),
                                pixelOps.getAmask()));
#ifndef _WIN32
                }
#endif
                SDL_SetColorKey(iconSurf.get(), SDL_TRUE, 0);
                SDL_SetWindowIcon(window.get(), iconSurf.get());
        }
}
 
void VisibleSurface::update(const Setting& /*setting*/) noexcept
{
        updateCursor();
}
 
void VisibleSurface::executeRT()
{
        // timer expired, hide cursor
        videoSystem.showCursor(false);
        inputEventGenerator.updateGrab(grab);
}
 
bool VisibleSurface::signalEvent(const Event& event)
{
        if (getType(event) == EventType::IMGUI_ACTIVE) {
                guiActive = get_event<ImGuiActiveEvent>(event).getActive();
        }
        updateCursor();
        return false;
}
 
void VisibleSurface::updateCursor()
{
        cancelRT();
        const auto& renderSettings = display.getRenderSettings();
        grab = !guiActive &&
               (renderSettings.getFullScreen() ||
                inputEventGenerator.getGrabInput().getBoolean());
        if (grab) {
                // always hide cursor in fullscreen or grab-input mode, but do it
                // after the derived class is constructed to avoid an SDL bug.
                scheduleRT(0);
                return;
        }
        inputEventGenerator.updateGrab(grab);
        float delay = renderSettings.getPointerHideDelay();
        if (delay == 0.0f) {
                videoSystem.showCursor(false);
        } else {
                videoSystem.showCursor(true);
                if (delay > 0.0f) {
                        scheduleRT(int(delay * 1e6f)); // delay in s, schedule in us
                }
        }
}
 
bool VisibleSurface::setFullScreen(bool fullscreen)
{
        auto flags = SDL_GetWindowFlags(window.get());
        // Note: SDL_WINDOW_FULLSCREEN_DESKTOP also has the SDL_WINDOW_FULLSCREEN
        //       bit set.
        if (bool currentState = (flags & SDL_WINDOW_FULLSCREEN) != 0;
            currentState == fullscreen) {
                // already wanted stated
                return true;
        }
 
        if (SDL_SetWindowFullscreen(window.get(),
                        fullscreen ? SDL_WINDOW_FULLSCREEN_DESKTOP : 0) != 0) {
                return false; // error, try re-creating the window
        }
        fullScreenUpdated(fullscreen);
        return true; // success
}
 
void VisibleSurface::resize()
{
        auto size = display.getWindowSize();
        SDL_SetWindowSize(window.get(), size.x, size.y);
 
        bool fullScreen = display.getRenderSettings().getFullScreen();
        setViewPort(size, fullScreen);
}
 
void VisibleSurface::updateWindowTitle()
{
        assert(window);
        SDL_SetWindowTitle(window.get(), getDisplay().getWindowTitle().c_str());
}
 
void VisibleSurface::saveScreenshot(const std::string& filename)
{
        saveScreenshotGL(*this, filename);
}
 
void VisibleSurface::saveScreenshotGL(
        const OutputSurface& output, const std::string& filename)
{
        auto [x, y] = output.getViewOffset();
        auto [w_, h_] = output.getViewSize();
        auto w = w_; // pre-clang-16 workaround
        auto h = h_;
 
        // OpenGL ES only supports reading RGBA (not RGB)
        MemBuffer<uint32_t> buffer(size_t(w) * size_t(h));
        glReadPixels(x, y, w, h, GL_RGBA, GL_UNSIGNED_BYTE, buffer.data());
 
        small_buffer<const uint32_t*, 1080> rowPointers(view::transform(xrange(size_t(h)),
                [&](auto i) { return &buffer[size_t(w) * (h - 1 - i)]; }));
 
        PNG::saveRGBA(w, rowPointers, filename);
}
 
void VisibleSurface::finish()
{
        SDL_GL_SwapWindow(window.get());
}
 
std::unique_ptr<Layer> VisibleSurface::createSnowLayer()
{
        return std::make_unique<GLSnow>(getDisplay());
}
 
std::unique_ptr<Layer> VisibleSurface::createOSDGUILayer(OSDGUI& gui)
{
        return std::make_unique<OSDGUILayer>(gui);
}
 
std::unique_ptr<Layer> VisibleSurface::createImGUILayer(ImGuiManager& manager)
{
        return std::make_unique<ImGuiLayer>(manager);
}
 
std::unique_ptr<OutputSurface> VisibleSurface::createOffScreenSurface()
{
        return std::make_unique<OffScreenSurface>(*this);
}
 
void VisibleSurface::VSyncObserver::update(const Setting& setting) noexcept
{
        const auto& visSurface = OUTER(VisibleSurface, vSyncObserver);
        const auto& syncSetting = visSurface.getDisplay().getRenderSettings().getVSyncSetting();
        assert(&setting == &syncSetting); (void)setting;
 
        // for now, we assume that adaptive vsync is the best kind of vsync, so when
        // vsync is enabled, we attempt adaptive vsync.
        int interval = syncSetting.getBoolean() ? -1 : 0;
 
        if ((SDL_GL_SetSwapInterval(interval) < 0) && (interval == -1)) {
                // "Adaptive vsync" is not supported by all drivers. SDL
                // documentation suggests to fallback to "regular vsync" in
                // that case.
                SDL_GL_SetSwapInterval(1);
        }
}
 
void VisibleSurface::setViewPort(gl::ivec2 logicalSize, bool fullScreen)
{
        gl::ivec2 physicalSize = [&] {
#ifndef __APPLE__
                // On macos we set 'SDL_WINDOW_ALLOW_HIGHDPI', and in that case
                // it's required to use SDL_GL_GetDrawableSize(), but then this
                // 'full screen'-workaround/hack is counter-productive.
                if (!fullScreen) {
                        // ??? When switching  back from full screen to windowed mode,
                        // SDL_GL_GetDrawableSize() still returns the dimensions of the
                        // full screen window ??? Is this a bug ???
                        // But we know that in windowed mode, physical and logical size
                        // must be the same, so enforce that.
                        return logicalSize;
                }
#endif
                (void)fullScreen;
                int w, h;
                SDL_GL_GetDrawableSize(window.get(), &w, &h);
                return gl::ivec2(w, h);
        }();
 
        // The created surface may be larger than requested.
        // If that happens, center the area that we actually use.
        calculateViewPort(logicalSize, physicalSize);
        // actually setting the viewport is done in PostProcessor::paint()
 
        gl::context->setupMvpMatrix(gl::vec2(logicalSize));
}
 
void VisibleSurface::fullScreenUpdated(bool fullScreen)
{
        setViewPort(getLogicalSize(), fullScreen);
}
 
} // namespace openmsx