/* * CGuiHandler.cpp, part of VCMI engine * * Authors: listed in file AUTHORS in main folder * * License: GNU General Public License v2.0 or later * Full text of license available in license.txt file, in main folder * */ #include "StdInc.h" #include "CGuiHandler.h" #include "../lib/CondSh.h" #include "CIntObject.h" #include "CursorHandler.h" #include "../CGameInfo.h" #include "../render/Colors.h" #include "../renderSDL/SDL_Extensions.h" #include "../CMT.h" #include "../CPlayerInterface.h" #include "../battle/BattleInterface.h" #include "../../lib/CThreadHelper.h" #include "../../lib/CConfigHandler.h" #include #include #include #ifdef VCMI_APPLE #include #endif #ifdef VCMI_IOS #include "ios/utils.h" #endif extern std::queue SDLEventsQueue; extern boost::mutex eventsM; boost::thread_specific_ptr inGuiThread; SObjectConstruction::SObjectConstruction(CIntObject *obj) :myObj(obj) { GH.createdObj.push_front(obj); GH.captureChildren = true; } SObjectConstruction::~SObjectConstruction() { assert(GH.createdObj.size()); assert(GH.createdObj.front() == myObj); GH.createdObj.pop_front(); GH.captureChildren = GH.createdObj.size(); } SSetCaptureState::SSetCaptureState(bool allow, ui8 actions) { previousCapture = GH.captureChildren; GH.captureChildren = false; prevActions = GH.defActionsDef; GH.defActionsDef = actions; } SSetCaptureState::~SSetCaptureState() { GH.captureChildren = previousCapture; GH.defActionsDef = prevActions; } static inline void processList(const ui16 mask, const ui16 flag, std::list *lst, std::function *)> cb) { if (mask & flag) cb(lst); } void CGuiHandler::processLists(const ui16 activityFlag, std::function *)> cb) { processList(CIntObject::LCLICK,activityFlag,&lclickable,cb); processList(CIntObject::RCLICK,activityFlag,&rclickable,cb); processList(CIntObject::MCLICK,activityFlag,&mclickable,cb); processList(CIntObject::HOVER,activityFlag,&hoverable,cb); processList(CIntObject::MOVE,activityFlag,&motioninterested,cb); processList(CIntObject::KEYBOARD,activityFlag,&keyinterested,cb); processList(CIntObject::TIME,activityFlag,&timeinterested,cb); processList(CIntObject::WHEEL,activityFlag,&wheelInterested,cb); processList(CIntObject::DOUBLECLICK,activityFlag,&doubleClickInterested,cb); processList(CIntObject::TEXTINPUT,activityFlag,&textInterested,cb); } void CGuiHandler::init() { mainFPSmng = new CFramerateManager(); mainFPSmng->init(settings["video"]["targetfps"].Integer()); isPointerRelativeMode = settings["general"]["userRelativePointer"].Bool(); pointerSpeedMultiplier = settings["general"]["relativePointerSpeedMultiplier"].Float(); } void CGuiHandler::handleElementActivate(CIntObject * elem, ui16 activityFlag) { processLists(activityFlag,[&](std::list * lst){ lst->push_front(elem); }); elem->active_m |= activityFlag; } void CGuiHandler::handleElementDeActivate(CIntObject * elem, ui16 activityFlag) { processLists(activityFlag,[&](std::list * lst){ auto hlp = std::find(lst->begin(),lst->end(),elem); assert(hlp != lst->end()); lst->erase(hlp); }); elem->active_m &= ~activityFlag; } void CGuiHandler::popInt(std::shared_ptr top) { assert(listInt.front() == top); top->deactivate(); disposed.push_back(top); listInt.pop_front(); objsToBlit -= top; if(!listInt.empty()) listInt.front()->activate(); totalRedraw(); } void CGuiHandler::pushInt(std::shared_ptr newInt) { assert(newInt); assert(!vstd::contains(listInt, newInt)); // do not add same object twice //a new interface will be present, we'll need to use buffer surface (unless it's advmapint that will alter screenBuf on activate anyway) screenBuf = screen2; if(!listInt.empty()) listInt.front()->deactivate(); listInt.push_front(newInt); CCS->curh->set(Cursor::Map::POINTER); newInt->activate(); objsToBlit.push_back(newInt); totalRedraw(); } void CGuiHandler::popInts(int howMany) { if(!howMany) return; //senseless but who knows... assert(listInt.size() >= howMany); listInt.front()->deactivate(); for(int i=0; i < howMany; i++) { objsToBlit -= listInt.front(); disposed.push_back(listInt.front()); listInt.pop_front(); } if(!listInt.empty()) { listInt.front()->activate(); totalRedraw(); } fakeMouseMove(); } std::shared_ptr CGuiHandler::topInt() { if(listInt.empty()) return std::shared_ptr(); else return listInt.front(); } void CGuiHandler::totalRedraw() { #ifdef VCMI_ANDROID SDL_FillRect(screen2, NULL, SDL_MapRGB(screen2->format, 0, 0, 0)); #endif for(auto & elem : objsToBlit) elem->showAll(screen2); CSDL_Ext::blitAt(screen2,0,0,screen); } void CGuiHandler::updateTime() { int ms = mainFPSmng->getElapsedMilliseconds(); std::list hlp = timeinterested; for (auto & elem : hlp) { if(!vstd::contains(timeinterested,elem)) continue; (elem)->onTimer(ms); } } void CGuiHandler::handleEvents() { //player interface may want special event handling if(nullptr != LOCPLINT && LOCPLINT->capturedAllEvents()) return; boost::unique_lock lock(eventsM); while(!SDLEventsQueue.empty()) { continueEventHandling = true; SDL_Event currentEvent = SDLEventsQueue.front(); if (currentEvent.type == SDL_MOUSEMOTION) { cursorPosition = Point(currentEvent.motion.x, currentEvent.motion.y); mouseButtonsMask = currentEvent.motion.state; } SDLEventsQueue.pop(); // In a sequence of mouse motion events, skip all but the last one. // This prevents freezes when every motion event takes longer to handle than interval at which // the events arrive (like dragging on the minimap in world view, with redraw at every event) // so that the events would start piling up faster than they can be processed. if ((currentEvent.type == SDL_MOUSEMOTION) && !SDLEventsQueue.empty() && (SDLEventsQueue.front().type == SDL_MOUSEMOTION)) continue; handleCurrentEvent(currentEvent); } } void CGuiHandler::convertTouchToMouse(SDL_Event * current) { int rLogicalWidth, rLogicalHeight; SDL_RenderGetLogicalSize(mainRenderer, &rLogicalWidth, &rLogicalHeight); int adjustedMouseY = (int)(current->tfinger.y * rLogicalHeight); int adjustedMouseX = (int)(current->tfinger.x * rLogicalWidth); current->button.x = adjustedMouseX; current->motion.x = adjustedMouseX; current->button.y = adjustedMouseY; current->motion.y = adjustedMouseY; } void CGuiHandler::fakeMoveCursor(float dx, float dy) { int x, y, w, h; SDL_Event event; SDL_MouseMotionEvent sme = {SDL_MOUSEMOTION, 0, 0, 0, 0, 0, 0, 0, 0}; sme.state = SDL_GetMouseState(&x, &y); SDL_GetWindowSize(mainWindow, &w, &h); sme.x = CCS->curh->position().x + (int)(GH.pointerSpeedMultiplier * w * dx); sme.y = CCS->curh->position().y + (int)(GH.pointerSpeedMultiplier * h * dy); vstd::abetween(sme.x, 0, w); vstd::abetween(sme.y, 0, h); event.motion = sme; SDL_PushEvent(&event); } void CGuiHandler::fakeMouseMove() { fakeMoveCursor(0, 0); } void CGuiHandler::startTextInput(const Rect & whereInput) { #ifdef VCMI_APPLE dispatch_async(dispatch_get_main_queue(), ^{ #endif // TODO ios: looks like SDL bug actually, try fixing there auto renderer = SDL_GetRenderer(mainWindow); float scaleX, scaleY; SDL_Rect viewport; SDL_RenderGetScale(renderer, &scaleX, &scaleY); SDL_RenderGetViewport(renderer, &viewport); #ifdef VCMI_IOS const auto nativeScale = iOS_utils::screenScale(); scaleX /= nativeScale; scaleY /= nativeScale; #endif SDL_Rect rectInScreenCoordinates; rectInScreenCoordinates.x = (viewport.x + whereInput.x) * scaleX; rectInScreenCoordinates.y = (viewport.y + whereInput.y) * scaleY; rectInScreenCoordinates.w = whereInput.w * scaleX; rectInScreenCoordinates.h = whereInput.h * scaleY; SDL_SetTextInputRect(&rectInScreenCoordinates); if (SDL_IsTextInputActive() == SDL_FALSE) { SDL_StartTextInput(); } #ifdef VCMI_APPLE }); #endif } void CGuiHandler::stopTextInput() { #ifdef VCMI_APPLE dispatch_async(dispatch_get_main_queue(), ^{ #endif if (SDL_IsTextInputActive() == SDL_TRUE) { SDL_StopTextInput(); } #ifdef VCMI_APPLE }); #endif } void CGuiHandler::fakeMouseButtonEventRelativeMode(bool down, bool right) { SDL_Event event; SDL_MouseButtonEvent sme = {SDL_MOUSEBUTTONDOWN, 0, 0, 0, 0, 0, 0, 0, 0, 0}; if(!down) { sme.type = SDL_MOUSEBUTTONUP; } sme.button = right ? SDL_BUTTON_RIGHT : SDL_BUTTON_LEFT; sme.x = CCS->curh->position().x; sme.y = CCS->curh->position().y; float xScale, yScale; int w, h, rLogicalWidth, rLogicalHeight; SDL_GetWindowSize(mainWindow, &w, &h); SDL_RenderGetLogicalSize(mainRenderer, &rLogicalWidth, &rLogicalHeight); SDL_RenderGetScale(mainRenderer, &xScale, &yScale); SDL_EventState(SDL_MOUSEMOTION, SDL_IGNORE); moveCursorToPosition( Point( (int)(sme.x * xScale) + (w - rLogicalWidth * xScale) / 2, (int)(sme.y * yScale + (h - rLogicalHeight * yScale) / 2))); SDL_EventState(SDL_MOUSEMOTION, SDL_ENABLE); event.button = sme; SDL_PushEvent(&event); } void CGuiHandler::handleCurrentEvent( SDL_Event & current ) { if(current.type == SDL_KEYDOWN || current.type == SDL_KEYUP) { SDL_KeyboardEvent key = current.key; if(current.type == SDL_KEYDOWN && key.keysym.sym >= SDLK_F1 && key.keysym.sym <= SDLK_F15 && settings["session"]["spectate"].Bool()) { //TODO: we need some central place for all interface-independent hotkeys Settings s = settings.write["session"]; switch(key.keysym.sym) { case SDLK_F5: if(settings["session"]["spectate-locked-pim"].Bool()) LOCPLINT->pim->unlock(); else LOCPLINT->pim->lock(); s["spectate-locked-pim"].Bool() = !settings["session"]["spectate-locked-pim"].Bool(); break; case SDLK_F6: s["spectate-ignore-hero"].Bool() = !settings["session"]["spectate-ignore-hero"].Bool(); break; case SDLK_F7: s["spectate-skip-battle"].Bool() = !settings["session"]["spectate-skip-battle"].Bool(); break; case SDLK_F8: s["spectate-skip-battle-result"].Bool() = !settings["session"]["spectate-skip-battle-result"].Bool(); break; case SDLK_F9: //not working yet since CClient::run remain locked after BattleInterface removal // if(LOCPLINT->battleInt) // { // GH.popInts(1); // vstd::clear_pointer(LOCPLINT->battleInt); // } break; default: break; } return; } //translate numpad keys if(key.keysym.sym == SDLK_KP_ENTER) { key.keysym.sym = SDLK_RETURN; key.keysym.scancode = SDL_SCANCODE_RETURN; } bool keysCaptured = false; for(auto i = keyinterested.begin(); i != keyinterested.end() && continueEventHandling; i++) { if((*i)->captureThisKey(key.keysym.sym)) { keysCaptured = true; break; } } std::list miCopy = keyinterested; for(auto i = miCopy.begin(); i != miCopy.end() && continueEventHandling; i++) if(vstd::contains(keyinterested,*i) && (!keysCaptured || (*i)->captureThisKey(key.keysym.sym))) { if (key.state == SDL_PRESSED) (**i).keyPressed(key.keysym.sym); if (key.state == SDL_RELEASED) (**i).keyReleased(key.keysym.sym); } } else if(current.type == SDL_MOUSEMOTION) { handleMouseMotion(current); } else if(current.type == SDL_MOUSEBUTTONDOWN) { switch(current.button.button) { case SDL_BUTTON_LEFT: { auto doubleClicked = false; if(lastClick == getCursorPosition() && (SDL_GetTicks() - lastClickTime) < 300) { std::list hlp = doubleClickInterested; for(auto i = hlp.begin(); i != hlp.end() && continueEventHandling; i++) { if(!vstd::contains(doubleClickInterested, *i)) continue; if((*i)->pos.isInside(current.motion.x, current.motion.y)) { (*i)->onDoubleClick(); doubleClicked = true; } } } lastClick = current.motion; lastClickTime = SDL_GetTicks(); if(!doubleClicked) handleMouseButtonClick(lclickable, MouseButton::LEFT, true); break; } case SDL_BUTTON_RIGHT: handleMouseButtonClick(rclickable, MouseButton::RIGHT, true); break; case SDL_BUTTON_MIDDLE: handleMouseButtonClick(mclickable, MouseButton::MIDDLE, true); break; default: break; } } else if(current.type == SDL_MOUSEWHEEL) { std::list hlp = wheelInterested; for(auto i = hlp.begin(); i != hlp.end() && continueEventHandling; i++) { if(!vstd::contains(wheelInterested,*i)) continue; // SDL doesn't have the proper values for mouse positions on SDL_MOUSEWHEEL, refetch them int x = 0, y = 0; SDL_GetMouseState(&x, &y); (*i)->wheelScrolled(current.wheel.y < 0, (*i)->pos.isInside(x, y)); } } else if(current.type == SDL_TEXTINPUT) { for(auto it : textInterested) { it->textInputed(current.text.text); } } else if(current.type == SDL_TEXTEDITING) { for(auto it : textInterested) { it->textEdited(current.edit.text); } } else if(current.type == SDL_MOUSEBUTTONUP) { if(!multifinger) { switch(current.button.button) { case SDL_BUTTON_LEFT: handleMouseButtonClick(lclickable, MouseButton::LEFT, false); break; case SDL_BUTTON_RIGHT: handleMouseButtonClick(rclickable, MouseButton::RIGHT, false); break; case SDL_BUTTON_MIDDLE: handleMouseButtonClick(mclickable, MouseButton::MIDDLE, false); break; } } } else if(current.type == SDL_FINGERMOTION) { if(isPointerRelativeMode) { fakeMoveCursor(current.tfinger.dx, current.tfinger.dy); } } else if(current.type == SDL_FINGERDOWN) { auto fingerCount = SDL_GetNumTouchFingers(current.tfinger.touchId); multifinger = fingerCount > 1; if(isPointerRelativeMode) { if(current.tfinger.x > 0.5) { bool isRightClick = current.tfinger.y < 0.5; fakeMouseButtonEventRelativeMode(true, isRightClick); } } #ifndef VCMI_IOS else if(fingerCount == 2) { convertTouchToMouse(¤t); handleMouseMotion(current); handleMouseButtonClick(rclickable, MouseButton::RIGHT, true); } #endif //VCMI_IOS } else if(current.type == SDL_FINGERUP) { #ifndef VCMI_IOS auto fingerCount = SDL_GetNumTouchFingers(current.tfinger.touchId); #endif //VCMI_IOS if(isPointerRelativeMode) { if(current.tfinger.x > 0.5) { bool isRightClick = current.tfinger.y < 0.5; fakeMouseButtonEventRelativeMode(false, isRightClick); } } #ifndef VCMI_IOS else if(multifinger) { convertTouchToMouse(¤t); handleMouseMotion(current); handleMouseButtonClick(rclickable, MouseButton::RIGHT, false); multifinger = fingerCount != 0; } #endif //VCMI_IOS } } //event end void CGuiHandler::handleMouseButtonClick(CIntObjectList & interestedObjs, MouseButton btn, bool isPressed) { auto hlp = interestedObjs; for(auto i = hlp.begin(); i != hlp.end() && continueEventHandling; i++) { if(!vstd::contains(interestedObjs, *i)) continue; auto prev = (*i)->mouseState(btn); if(!isPressed) (*i)->updateMouseState(btn, isPressed); if((*i)->pos.isInside(getCursorPosition())) { if(isPressed) (*i)->updateMouseState(btn, isPressed); (*i)->click(btn, isPressed, prev); } else if(!isPressed) (*i)->click(btn, boost::logic::indeterminate, prev); } } void CGuiHandler::handleMouseMotion(const SDL_Event & current) { //sending active, hovered hoverable objects hover() call std::vector hlp; auto hoverableCopy = hoverable; for(auto & elem : hoverableCopy) { if(elem->pos.isInside(getCursorPosition())) { if (!(elem)->hovered) hlp.push_back((elem)); } else if ((elem)->hovered) { (elem)->hover(false); (elem)->hovered = false; } } for(auto & elem : hlp) { elem->hover(true); elem->hovered = true; } // do not send motion events for events outside our window //if (current.motion.windowID == 0) handleMoveInterested(current.motion); } void CGuiHandler::simpleRedraw() { //update only top interface and draw background if(objsToBlit.size() > 1) CSDL_Ext::blitAt(screen2,0,0,screen); //blit background if(!objsToBlit.empty()) objsToBlit.back()->show(screen); //blit active interface/window } void CGuiHandler::handleMoveInterested(const SDL_MouseMotionEvent & motion) { //sending active, MotionInterested objects mouseMoved() call std::list miCopy = motioninterested; for(auto & elem : miCopy) { if(elem->strongInterest || Rect::createAround(elem->pos, 1).isInside( motion.x, motion.y)) //checking bounds including border fixes bug #2476 { (elem)->mouseMoved(Point(motion.x, motion.y)); } } } void CGuiHandler::renderFrame() { // Updating GUI requires locking pim mutex (that protects screen and GUI state). // During game: // When ending the game, the pim mutex might be hold by other thread, // that will notify us about the ending game by setting terminate_cond flag. //in PreGame terminate_cond stay false bool acquiredTheLockOnPim = false; //for tracking whether pim mutex locking succeeded while(!terminate_cond->get() && !(acquiredTheLockOnPim = CPlayerInterface::pim->try_lock())) //try acquiring long until it succeeds or we are told to terminate boost::this_thread::sleep(boost::posix_time::milliseconds(1)); if(acquiredTheLockOnPim) { // If we are here, pim mutex has been successfully locked - let's store it in a safe RAII lock. boost::unique_lock un(*CPlayerInterface::pim, boost::adopt_lock); if(nullptr != curInt) curInt->update(); if(settings["video"]["showfps"].Bool()) drawFPSCounter(); SDL_UpdateTexture(screenTexture, nullptr, screen->pixels, screen->pitch); SDL_RenderClear(mainRenderer); SDL_RenderCopy(mainRenderer, screenTexture, nullptr, nullptr); CCS->curh->render(); SDL_RenderPresent(mainRenderer); disposed.clear(); } mainFPSmng->framerateDelay(); // holds a constant FPS } CGuiHandler::CGuiHandler() : lastClick(-500, -500) , lastClickTime(0) , defActionsDef(0) , captureChildren(false) , multifinger(false) , mouseButtonsMask(0) , continueEventHandling(true) , curInt(nullptr) , mainFPSmng(nullptr) , statusbar(nullptr) { terminate_cond = new CondSh(false); } CGuiHandler::~CGuiHandler() { delete mainFPSmng; delete terminate_cond; } void CGuiHandler::moveCursorToPosition(const Point & position) { SDL_WarpMouseInWindow(mainWindow, position.x, position.y); } bool CGuiHandler::isKeyboardCtrlDown() const { return SDL_GetKeyboardState(nullptr)[SDL_SCANCODE_LCTRL] || SDL_GetKeyboardState(nullptr)[SDL_SCANCODE_RCTRL]; } bool CGuiHandler::isKeyboardAltDown() const { return SDL_GetKeyboardState(nullptr)[SDL_SCANCODE_LALT] || SDL_GetKeyboardState(nullptr)[SDL_SCANCODE_RALT]; } bool CGuiHandler::isKeyboardShiftDown() const { return SDL_GetKeyboardState(nullptr)[SDL_SCANCODE_LSHIFT] || SDL_GetKeyboardState(nullptr)[SDL_SCANCODE_RSHIFT]; } void CGuiHandler::breakEventHandling() { continueEventHandling = false; } const Point & CGuiHandler::getCursorPosition() const { return cursorPosition; } Point CGuiHandler::screenDimensions() const { return Point(screen->w, screen->h); } bool CGuiHandler::isMouseButtonPressed() const { return mouseButtonsMask > 0; } bool CGuiHandler::isMouseButtonPressed(MouseButton button) const { static_assert(static_cast(MouseButton::LEFT) == SDL_BUTTON_LEFT, "mismatch between VCMI and SDL enum!"); static_assert(static_cast(MouseButton::MIDDLE) == SDL_BUTTON_MIDDLE, "mismatch between VCMI and SDL enum!"); static_assert(static_cast(MouseButton::RIGHT) == SDL_BUTTON_RIGHT, "mismatch between VCMI and SDL enum!"); static_assert(static_cast(MouseButton::EXTRA1) == SDL_BUTTON_X1, "mismatch between VCMI and SDL enum!"); static_assert(static_cast(MouseButton::EXTRA2) == SDL_BUTTON_X2, "mismatch between VCMI and SDL enum!"); uint32_t index = static_cast(button); return mouseButtonsMask & SDL_BUTTON(index); } void CGuiHandler::drawFPSCounter() { static SDL_Rect overlay = { 0, 0, 64, 32}; uint32_t black = SDL_MapRGB(screen->format, 10, 10, 10); SDL_FillRect(screen, &overlay, black); std::string fps = std::to_string(mainFPSmng->getFramerate()); graphics->fonts[FONT_BIG]->renderTextLeft(screen, fps, Colors::YELLOW, Point(10, 10)); } SDL_Keycode CGuiHandler::arrowToNum(SDL_Keycode key) { switch(key) { case SDLK_DOWN: return SDLK_KP_2; case SDLK_UP: return SDLK_KP_8; case SDLK_LEFT: return SDLK_KP_4; case SDLK_RIGHT: return SDLK_KP_6; default: throw std::runtime_error("Wrong key!"); } } SDL_Keycode CGuiHandler::numToDigit(SDL_Keycode key) { #define REMOVE_KP(keyName) case SDLK_KP_ ## keyName : return SDLK_ ## keyName; switch(key) { REMOVE_KP(0) REMOVE_KP(1) REMOVE_KP(2) REMOVE_KP(3) REMOVE_KP(4) REMOVE_KP(5) REMOVE_KP(6) REMOVE_KP(7) REMOVE_KP(8) REMOVE_KP(9) REMOVE_KP(PERIOD) REMOVE_KP(MINUS) REMOVE_KP(PLUS) REMOVE_KP(EQUALS) case SDLK_KP_MULTIPLY: return SDLK_ASTERISK; case SDLK_KP_DIVIDE: return SDLK_SLASH; case SDLK_KP_ENTER: return SDLK_RETURN; default: return SDLK_UNKNOWN; } #undef REMOVE_KP } bool CGuiHandler::isNumKey(SDL_Keycode key, bool number) { if(number) return key >= SDLK_KP_1 && key <= SDLK_KP_0; else return (key >= SDLK_KP_1 && key <= SDLK_KP_0) || key == SDLK_KP_MINUS || key == SDLK_KP_PLUS || key == SDLK_KP_EQUALS; } bool CGuiHandler::isArrowKey(SDL_Keycode key) { return key == SDLK_UP || key == SDLK_DOWN || key == SDLK_LEFT || key == SDLK_RIGHT; } bool CGuiHandler::amIGuiThread() { return inGuiThread.get() && *inGuiThread; } void CGuiHandler::pushUserEvent(EUserEvent usercode) { pushUserEvent(usercode, nullptr); } void CGuiHandler::pushUserEvent(EUserEvent usercode, void * userdata) { SDL_Event event; event.type = SDL_USEREVENT; event.user.code = static_cast(usercode); event.user.data1 = userdata; SDL_PushEvent(&event); } CFramerateManager::CFramerateManager() : rate(0) , rateticks(0) , fps(0) , accumulatedFrames(0) , accumulatedTime(0) , lastticks(0) , timeElapsed(0) {} void CFramerateManager::init(int newRate) { rate = newRate; rateticks = 1000.0 / rate; this->lastticks = SDL_GetTicks(); } void CFramerateManager::framerateDelay() { ui32 currentTicks = SDL_GetTicks(); timeElapsed = currentTicks - lastticks; accumulatedFrames++; // FPS is higher than it should be, then wait some time if(timeElapsed < rateticks) { int timeToSleep = (uint32_t)ceil(this->rateticks) - timeElapsed; boost::this_thread::sleep(boost::posix_time::milliseconds(timeToSleep)); } currentTicks = SDL_GetTicks(); // recalculate timeElapsed for external calls via getElapsed() // limit it to 100 ms to avoid breaking animation in case of huge lag (e.g. triggered breakpoint) timeElapsed = std::min(currentTicks - lastticks, 100); lastticks = SDL_GetTicks(); accumulatedTime += timeElapsed; if(accumulatedFrames >= 100) { //about 2 second should be passed fps = static_cast(ceil(1000.0 / (accumulatedTime / accumulatedFrames))); accumulatedTime = 0; accumulatedFrames = 0; } }