Display.cc

Go to the documentation of this file.

#include "Display.hh"
 
#include "RendererFactory.hh"
#include "ImGuiManager.hh"
#include "Layer.hh"
#include "OutputSurface.hh"
#include "VideoLayer.hh"
#include "VideoSystem.hh"
#include "VideoSystemChangeListener.hh"
 
#include "BooleanSetting.hh"
#include "CommandException.hh"
#include "EventDistributor.hh"
#include "Event.hh"
#include "FileOperations.hh"
#include "FileContext.hh"
#include "CliComm.hh"
#include "Timer.hh"
#include "IntegerSetting.hh"
#include "EnumSetting.hh"
#include "Reactor.hh"
#include "MSXMotherBoard.hh"
#include "HardwareConfig.hh"
#include "TclArgParser.hh"
#include "XMLElement.hh"
#include "Version.hh"
 
#include "narrow.hh"
#include "outer.hh"
#include "ranges.hh"
#include "stl.hh"
#include "unreachable.hh"
#include "xrange.hh"
 
#include <array>
#include <cassert>
 
using std::string;
 
namespace openmsx {
 
Display::Display(Reactor& reactor_)
        : RTSchedulable(reactor_.getRTScheduler())
        , screenShotCmd(reactor_.getCommandController())
        , fpsInfo(reactor_.getOpenMSXInfoCommand())
        , osdGui(reactor_.getCommandController(), *this)
        , reactor(reactor_)
        , renderSettings(reactor.getCommandController())
{
        frameDurationSum = 0;
        repeat(NUM_FRAME_DURATIONS, [&] {
                frameDurations.addFront(20);
                frameDurationSum += 20;
        });
        prevTimeStamp = Timer::getTime();
 
        EventDistributor& eventDistributor = reactor.getEventDistributor();
        using enum EventType;
        for (auto type : {FINISH_FRAME, SWITCH_RENDERER, MACHINE_LOADED, WINDOW}) {
                eventDistributor.registerEventListener(type, *this);
        }
 
        renderSettings.getRendererSetting().attach(*this);
}
 
Display::~Display()
{
        renderSettings.getRendererSetting().detach(*this);
 
        EventDistributor& eventDistributor = reactor.getEventDistributor();
        using enum EventType;
        for (auto type : {WINDOW, MACHINE_LOADED, SWITCH_RENDERER, FINISH_FRAME}) {
                eventDistributor.unregisterEventListener(type, *this);
        }
 
        resetVideoSystem();
 
        assert(listeners.empty());
}
 
void Display::createVideoSystem()
{
        assert(!videoSystem);
        assert(currentRenderer == RenderSettings::RendererID::UNINITIALIZED);
        assert(!switchInProgress);
        currentRenderer = renderSettings.getRenderer();
        switchInProgress = true;
        doRendererSwitch();
}
 
VideoSystem& Display::getVideoSystem()
{
        assert(videoSystem);
        return *videoSystem;
}
 
OutputSurface* Display::getOutputSurface()
{
        return videoSystem ? videoSystem->getOutputSurface() : nullptr;
}
 
void Display::resetVideoSystem()
{
        videoSystem.reset();
        // At this point all layers except for the Video9000 layer
        // should be gone.
        //assert(layers.empty());
}
 
CliComm& Display::getCliComm() const
{
        return reactor.getCliComm();
}
 
void Display::attach(VideoSystemChangeListener& listener)
{
        assert(!contains(listeners, &listener));
        listeners.push_back(&listener);
}
 
void Display::detach(VideoSystemChangeListener& listener)
{
        move_pop_back(listeners, rfind_unguarded(listeners, &listener));
}
 
Layer* Display::findActiveLayer() const
{
        auto it = ranges::find_if(layers, &Layer::isActive);
        return (it != layers.end()) ? *it : nullptr;
}
 
Display::Layers::iterator Display::baseLayer()
{
        // Note: It is possible to cache this, but since the number of layers is
        //       low at the moment, it's not really worth it.
        auto it = end(layers);
        while (true) {
                if (it == begin(layers)) {
                        // There should always be at least one opaque layer.
                        // TODO: This is not true for DummyVideoSystem.
                        //       Anyway, a missing layer will probably stand out visually,
                        //       so do we really have to assert on it?
                        //UNREACHABLE;
                        return it;
                }
                --it;
                if ((*it)->getCoverage() == Layer::Coverage::FULL) return it;
        }
}
 
void Display::executeRT()
{
        repaint();
}
 
int Display::signalEvent(const Event& event)
{
        std::visit(overloaded{
                [&](const FinishFrameEvent& e) {
                        if (e.needRender()) {
                                repaint();
                                reactor.getEventDistributor().distributeEvent(FrameDrawnEvent());
                        }
                },
                [&](const SwitchRendererEvent& /*e*/) {
                        doRendererSwitch(); // might throw
                },
                [&](const MachineLoadedEvent& /*e*/) {
                        videoSystem->updateWindowTitle();
                },
                [&](const WindowEvent& e) {
                        const auto& evt = e.getSdlWindowEvent();
                        if (evt.event == SDL_WINDOWEVENT_EXPOSED) {
                                // Don't render too often, and certainly not when the screen
                                // will anyway soon be rendered.
                                repaintDelayed(100 * 1000); // 10fps
                        }
                        if (PLATFORM_ANDROID && e.isMainWindow() &&
                            evt.event == one_of(SDL_WINDOWEVENT_FOCUS_GAINED, SDL_WINDOWEVENT_FOCUS_LOST)) {
                                // On Android, the rendering must be frozen when the app is sent to
                                // the background, because Android takes away all graphics resources
                                // from the app. It simply destroys the entire graphics context.
                                // Though, a repaint() must happen within the focus-lost event
                                // so that the SDL Android port realizes that the graphics context
                                // is gone and will re-build it again on the first flush to the
                                // surface after the focus has been regained.
 
                                // Perform a repaint before updating the renderFrozen flag:
                                // -When loosing the focus, this repaint will flush a last
                                //  time the SDL surface, making sure that the Android SDL
                                //  port discovers that the graphics context is gone.
                                // -When gaining the focus, this repaint does nothing as
                                //  the renderFrozen flag is still false
                                repaint();
                                bool lost = evt.event == SDL_WINDOWEVENT_FOCUS_LOST;
                                ad_printf("Setting renderFrozen to %d", lost);
                                renderFrozen = lost;
                        }
                },
                [](const EventBase&) { /*ignore*/ }
        }, event);
        return 0;
}
 
string Display::getWindowTitle()
{
        string title = Version::full();
        if (!Version::RELEASE) {
                strAppend(title, " [", BUILD_FLAVOUR, ']');
        }
        if (MSXMotherBoard* motherboard = reactor.getMotherBoard()) {
                if (const HardwareConfig* machine = motherboard->getMachineConfig()) {
                        const auto& config = machine->getConfig();
                        strAppend(title, " - ",
                                  config.getChild("info").getChildData("manufacturer"), ' ',
                                  config.getChild("info").getChildData("code"));
                }
        }
        return title;
}
 
gl::ivec2 Display::getWindowPosition()
{
        if (auto pos = videoSystem->getWindowPosition()) {
                storeWindowPosition(*pos);
        }
        return retrieveWindowPosition();
}
 
void Display::setWindowPosition(gl::ivec2 pos)
{
        storeWindowPosition(pos);
        videoSystem->setWindowPosition(pos);
}
 
void Display::storeWindowPosition(gl::ivec2 pos)
{
        reactor.getImGuiManager().storeWindowPosition(pos);
}
 
gl::ivec2 Display::retrieveWindowPosition()
{
        return reactor.getImGuiManager().retrieveWindowPosition();
}
 
void Display::update(const Setting& setting) noexcept
{
        if (&setting == &renderSettings.getRendererSetting()) {
                checkRendererSwitch();
        } else {
                UNREACHABLE;
        }
}
 
void Display::checkRendererSwitch()
{
        if (switchInProgress) {
                // This method only queues a request to switch renderer (see
                // comments below why). If there already is such a request
                // queued we don't need to do it again.
                return;
        }
        auto newRenderer = renderSettings.getRenderer();
        if (newRenderer != currentRenderer) {
                currentRenderer = newRenderer;
                // don't do the actual switching in the Tcl callback
                // it seems creating and destroying Settings (= Tcl vars)
                // causes problems???
                switchInProgress = true;
                reactor.getEventDistributor().distributeEvent(SwitchRendererEvent());
        }
}
 
void Display::doRendererSwitch()
{
        assert(switchInProgress);
 
        bool success = false;
        while (!success) {
                try {
                        doRendererSwitch2();
                        success = true;
                } catch (MSXException& e) {
                        auto& rendererSetting = renderSettings.getRendererSetting();
                        string errorMsg = strCat(
                                "Couldn't activate renderer ",
                                rendererSetting.getString(),
                                ": ", e.getMessage());
                        // now try some things that might work against this:
                        auto& scaleFactorSetting = renderSettings.getScaleFactorSetting();
                        auto curVal = scaleFactorSetting.getInt();
                        if (curVal == MIN_SCALE_FACTOR) {
                                throw FatalError(
                                        e.getMessage(),
                                        " (and I have no other ideas to try...)"); // give up and die... :(
                        }
                        strAppend(errorMsg, "\nTrying to decrease scale_factor setting from ",
                                        curVal, " to ", curVal - 1, "...");
                        scaleFactorSetting.setInt(curVal - 1);
                        getCliComm().printWarning(errorMsg);
                }
        }
 
        switchInProgress = false;
}
 
void Display::doRendererSwitch2()
{
        for (auto& l : listeners) {
                l->preVideoSystemChange();
        }
 
        resetVideoSystem();
        videoSystem = RendererFactory::createVideoSystem(reactor);
 
        for (auto& l : listeners) {
                l->postVideoSystemChange();
        }
}
 
void Display::repaintImpl()
{
        if (switchInProgress) {
                // The checkRendererSwitch() method will queue a
                // SWITCH_RENDERER_EVENT, but before that event is handled
                // we shouldn't do any repaints (with inconsistent setting
                // values and render objects). This can happen when this
                // method gets called because of a DELAYED_REPAINT_EVENT
                // (DELAYED_REPAINT_EVENT was already queued before
                // SWITCH_RENDERER_EVENT is queued).
                return;
        }
 
        cancelRT(); // cancel delayed repaint
 
        if (!renderFrozen) {
                assert(videoSystem);
                if (OutputSurface* surface = videoSystem->getOutputSurface()) {
                        repaintImpl(*surface);
                        videoSystem->flush();
                }
        }
 
        // update fps statistics
        auto now = Timer::getTime();
        auto duration = now - prevTimeStamp;
        prevTimeStamp = now;
        frameDurationSum += duration - frameDurations.removeBack();
        frameDurations.addFront(duration);
 
        // TODO maybe revisit this later (and/or simplify other calls to repaintDelayed())
        // This ensures a minimum framerate for ImGui
        repaintDelayed(40 * 1000); // 25fps
}
 
void Display::repaintImpl(OutputSurface& surface)
{
        for (auto it = baseLayer(); it != end(layers); ++it) {
                if ((*it)->getCoverage() != Layer::Coverage::NONE) {
                        (*it)->paint(surface);
                }
        }
}
 
void Display::repaint()
{
        // Request a repaint from the VideoSystem. This may call repaintImpl()
        // directly or for example defer to a signal callback on VisibleSurface.
        videoSystem->repaint();
}
 
void Display::repaintDelayed(uint64_t delta)
{
        if (isPendingRT()) {
                // already a pending repaint
                return;
        }
        scheduleRT(unsigned(delta));
}
 
void Display::addLayer(Layer& layer)
{
        int z = layer.getZ();
        auto it = ranges::find_if(layers, [&](const Layer* l) { return l->getZ() > z; });
        layers.insert(it, &layer);
        layer.setDisplay(*this);
}
 
void Display::removeLayer(Layer& layer)
{
        layers.erase(rfind_unguarded(layers, &layer));
}
 
void Display::updateZ(Layer& layer) noexcept
{
        // Remove at old Z-index...
        removeLayer(layer);
        // ...and re-insert at new Z-index.
        addLayer(layer);
}
 
 
// ScreenShotCmd
 
Display::ScreenShotCmd::ScreenShotCmd(CommandController& commandController_)
        : Command(commandController_, "screenshot")
{
}
 
void Display::ScreenShotCmd::execute(std::span<const TclObject> tokens, TclObject& result)
{
        std::string_view prefix = "openmsx";
        bool rawShot = false;
        bool msxOnly = false;
        bool doubleSize = false;
        bool withOsd = false;
        std::array info = {
                valueArg("-prefix", prefix),
                flagArg("-raw", rawShot),
                flagArg("-msxonly", msxOnly),
                flagArg("-doublesize", doubleSize),
                flagArg("-with-osd", withOsd)
        };
        auto arguments = parseTclArgs(getInterpreter(), tokens.subspan(1), info);
 
        auto& display = OUTER(Display, screenShotCmd);
        if (msxOnly) {
                display.getCliComm().printWarning(
                        "The -msxonly option has been deprecated and will "
                        "be removed in a future release. Instead, use the "
                        "-raw option for the same effect.");
                rawShot = true;
        }
        if (doubleSize && !rawShot) {
                throw CommandException("-doublesize option can only be used in "
                                       "combination with -raw");
        }
        if (rawShot && withOsd) {
                throw CommandException("-with-osd cannot be used in "
                                       "combination with -raw");
        }
 
        std::string_view fname;
        switch (arguments.size()) {
        case 0:
                // nothing
                break;
        case 1:
                fname = arguments[0].getString();
                break;
        default:
                throw SyntaxError();
        }
        string filename = FileOperations::parseCommandFileArgument(
                fname, SCREENSHOT_DIR, prefix, SCREENSHOT_EXTENSION);
 
        if (!rawShot) {
                // take screenshot as displayed, possibly with other layers (OSD stuff, ImGUI)
                try {
                        display.getVideoSystem().takeScreenShot(filename, withOsd);
                } catch (MSXException& e) {
                        throw CommandException(
                                "Failed to take screenshot: ", e.getMessage());
                }
        } else {
                auto* videoLayer = dynamic_cast<VideoLayer*>(
                        display.findActiveLayer());
                if (!videoLayer) {
                        throw CommandException(
                                "Current renderer doesn't support taking screenshots.");
                }
                unsigned height = doubleSize ? 480 : 240;
                try {
                        videoLayer->takeRawScreenShot(height, filename);
                } catch (MSXException& e) {
                        throw CommandException(
                                "Failed to take screenshot: ", e.getMessage());
                }
        }
 
        display.getCliComm().printInfo("Screen saved to ", filename);
        result = filename;
}
 
string Display::ScreenShotCmd::help(std::span<const TclObject> /*tokens*/) const
{
        // Note: -no-sprites and -guess-name options are implemented in Tcl.
        // TODO: find a way to extend the help and completion for a command
        // when extending it in Tcl
        return "screenshot                   Write screenshot to file \"openmsxNNNN.png\"\n"
               "screenshot <filename>        Write screenshot to indicated file\n"
               "screenshot -prefix foo       Write screenshot to file \"fooNNNN.png\"\n"
               "screenshot -raw              320x240 raw screenshot (of MSX screen only)\n"
               "screenshot -raw -doublesize  640x480 raw screenshot (of MSX screen only)\n"
               "screenshot -with-osd         Include OSD elements in the screenshot\n"
               "screenshot -no-sprites       Don't include sprites in the screenshot\n"
               "screenshot -guess-name       Guess the name of the running software and use it as prefix\n";
}
 
void Display::ScreenShotCmd::tabCompletion(std::vector<string>& tokens) const
{
        using namespace std::literals;
        static constexpr std::array extra = {
                "-prefix"sv, "-raw"sv, "-doublesize"sv, "-with-osd"sv, "-no-sprites"sv, "-guess-name"sv,
        };
        completeFileName(tokens, userFileContext(), extra);
}
 
 
// FpsInfoTopic
 
Display::FpsInfoTopic::FpsInfoTopic(InfoCommand& openMSXInfoCommand)
        : InfoTopic(openMSXInfoCommand, "fps")
{
}
 
void Display::FpsInfoTopic::execute(std::span<const TclObject> /*tokens*/,
                                    TclObject& result) const
{
        auto& display = OUTER(Display, fpsInfo);
        result = 1000000.0f * Display::NUM_FRAME_DURATIONS / narrow_cast<float>(display.frameDurationSum);
}
 
string Display::FpsInfoTopic::help(std::span<const TclObject> /*tokens*/) const
{
        return "Returns the current rendering speed in frames per second.";
}
 
} // namespace openmsx