crossplatform.cpp

#include "DxLib.h"
#include "main.h"
#include "global_vars.h"

#include "crossplatform.h"

#ifdef __EMSCRIPTEN__ // Emscripten

void MainloopEmscripten()
{
    UpdateKeys();
    SyobonQuit = 0;
    Mainprogram();
    if (SyobonQuit == 3)
        return;
    static int prevFPS = 30;
    if (prevFPS != xx[0])
    {
        // Restart the loop with a different Target FPS
        emscripten_cancel_main_loop();
        prevFPS = xx[0];
        emscripten_set_main_loop(MainloopEmscripten, xx[0], 1);
    }
}

void Empscripten_SetColorKey(SDL_Surface *pSurface, Uint32 Color)
{
    SDL_LockSurface(pSurface);

    union PixelColor32
    {
        Uint32 Pixel;
        Uint8 Colors[4];
    };

    PixelColor32 ColorKey;
    ColorKey.Pixel = Color;

    // Pixels are weird in emscripten for some reason and does not match exact value
    //(or it is just me being bad at Emscripten SDL)
    int Tolerance = 2;

    size_t max = pSurface->w * pSurface->h;
    for (int i = 0; i < max; ++i)
    {
        SDL_Color *pPixel = &((SDL_Color *)pSurface->pixels)[i];

        if (
            pPixel->r >= ColorKey.Colors[0] - Tolerance && pPixel->r < ColorKey.Colors[0] + Tolerance &&
            pPixel->g >= ColorKey.Colors[1] - Tolerance && pPixel->g < ColorKey.Colors[1] + Tolerance &&
            pPixel->b >= ColorKey.Colors[2] - Tolerance && pPixel->b < ColorKey.Colors[2] + Tolerance)
        {
            *((Uint32 *)pPixel) = 0;
        }
    }

    SDL_UnlockSurface(pSurface);
}

//+KZ: Emscripten needs a custom WaitKey, otherwise the browser will freeze
void Emscripten_WaitKey_Loop(void *args /* (args is not used and should not be) */)
{
    SDL_Event event;
    while (SDL_PollEvent(&event))
    {
        if (event.type == SDL_KEYDOWN)
        {
            return;
        }
    }
    //+KZ: keep pushing ourselves until a key is pressed
    emscripten_push_main_loop_blocker(Emscripten_WaitKey_Loop, nullptr);
}

//+KZ: starts the WaitKey loop
void Emscripten_WaitKey()
{
    emscripten_push_main_loop_blocker(Emscripten_WaitKey_Loop, nullptr);
}

#else

    #ifdef __ANDROID__

    bool HandleAppEvents(void *userdata, SDL_Event *event)
    {
        switch (event->type)
        {
        case SDL_EVENT_TERMINATING:
            /* Terminate the app.
            Shut everything down before returning from this function.
            */
            return false;
        case SDL_EVENT_LOW_MEMORY:
            /* You will get this when your app is paused and Android wants more memory.
            Release as much memory as possible.
            */
            return false;
        case SDL_EVENT_WILL_ENTER_BACKGROUND:
            /* Prepare your app to go into the background.  Stop loops, etc.
            This gets called when the user hits the home button, or gets a call.

            You should not make any OpenGL graphics calls or use the rendering API,
            in addition, you should set the render target to NULL, if you're using
            it, e.g. call SDL_SetRenderTarget(renderer, NULL).
            */
            return false;
        case SDL_EVENT_DID_ENTER_BACKGROUND:
            /* Your app is NOT active at this point. */
            return false;
        case SDL_EVENT_WILL_ENTER_FOREGROUND:
            /* This call happens when your app is coming back to the foreground.
            Restore all your state here.
            */
            return false;
        case SDL_EVENT_DID_ENTER_FOREGROUND:
            /* Restart your loops here.
            Your app is interactive and getting CPU again.

            You have access to the OpenGL context or rendering API at this point.
            However, there's a chance (on older hardware, or on systems under heavy load),
            where the graphics context cannot be restored. You should listen for the
            event SDL_EVENT_RENDER_DEVICE_RESET and recreate your OpenGL context and
            restore your textures when you get it, or quit the app.
            */
            return false;
        default:
            /* No special processing, add it to the event queue */
            return true;
        }
    }

    SDL_Rect LeftButton, RightButton, UpButton, DownButton, JumpButton, PauseButton;

    void UpdateTouchControls()
    {
        int w, h;
        if(!SDL_GetWindowSize(pWindow, &w, &h))
            return;

        //simple way to detect if phone is landscape so we put the buttons in a better position
        bool Landscape = w > h;

        int ButtonsSizeY = Landscape ? 150 : 130;
        int ButtonsStartX = Landscape ? 75 : 25;
        int ButtonsStartY = (h - ((Landscape ? 75 : 256) + ButtonsSizeY * 2)) + ButtonsSizeY / 2;

        //Left
        LeftButton = {ButtonsStartX, ButtonsStartY, ButtonsSizeY + ButtonsSizeY/2, ButtonsSizeY};
        RightButton = {LeftButton.x + LeftButton.w + 6, ButtonsStartY, ButtonsSizeY + ButtonsSizeY/2, ButtonsSizeY};
        DownButton = {LeftButton.x + (LeftButton.w + 6 * 2) / 2, ButtonsStartY + ButtonsSizeY + 6, ButtonsSizeY + ButtonsSizeY/2 + 3 * 2, ButtonsSizeY / 3 * 2};
        UpButton = DownButton;
        UpButton.y = LeftButton.y - (UpButton.h + 6);

        //UpRight
        PauseButton = {w - (ButtonsSizeY + ButtonsStartX), Landscape ? 50 : 125, ButtonsSizeY, ButtonsSizeY};

        //Right
        JumpButton = {w - (int)(ButtonsSizeY * 1.5f + ButtonsStartX), ButtonsStartY, (int)(ButtonsSizeY * 1.5f), (int)(ButtonsSizeY * 1.5f)};
    }

    void HandleTouchInput()
    {
        int devicecount = 0;
        SDL_TouchID * touchids = SDL_GetTouchDevices(&devicecount);
        
        if(!touchids)
            return;

        int w, h;
        if(!SDL_GetWindowSize(pWindow, &w, &h))
            return;

        for(int j = 0; j < devicecount; ++j)
        {
            //Release keys
            SetKeyState(KEY_INPUT_LEFT, false); 
            SetKeyState(KEY_INPUT_RIGHT, false);
            SetKeyState(KEY_INPUT_DOWN, false);
            SetKeyState(KEY_INPUT_UP, false);
            SetKeyState(KEY_INPUT_Z, false); //Jump, Start
            SetKeyState(KEY_INPUT_ESCAPE, false);

            int count = 0;
            SDL_Finger **fingers = SDL_GetTouchFingers(touchids[j], &count);

            for(int i = 0; i < count; i ++)
            {
                SDL_Point TouchedPos = {(int)(fingers[i]->x * w), (int)(fingers[i]->y * h)};

                if(SDL_PointInRect(&TouchedPos, &LeftButton))
                    SetKeyState(KEY_INPUT_LEFT, true); 
                else if(SDL_PointInRect(&TouchedPos, &RightButton))
                    SetKeyState(KEY_INPUT_RIGHT, true);
                else if(SDL_PointInRect(&TouchedPos, &DownButton))
                    SetKeyState(KEY_INPUT_DOWN, true); 
                else if(SDL_PointInRect(&TouchedPos, &UpButton))
                    SetKeyState(KEY_INPUT_UP, true); 
                else if(SDL_PointInRect(&TouchedPos, &JumpButton))
                    SetKeyState(KEY_INPUT_Z, true);
                else if(SDL_PointInRect(&TouchedPos, &PauseButton))
                    SetKeyState(KEY_INPUT_ESCAPE, true);

            }
        }
    }

    SDL_Surface * pDrawControlsSurface = nullptr;
    SDL_Texture * pDrawControlsTexture = nullptr;
    bool FirstRun = true;

    void DrawTouchControls()
    {
        int w, h;
        if(!SDL_GetWindowSize(pWindow, &w, &h))
            return;
        static int prev_window_w = -1, prev_window_h = -1;
        if(
            !pDrawControlsSurface ||
            !pDrawControlsTexture ||
            prev_window_w != w ||
            prev_window_h != h
        )
        {

            if(pDrawControlsSurface || FirstRun)
            {
                if(pDrawControlsSurface)
                    SDL_DestroySurface(pDrawControlsSurface);
                pDrawControlsSurface = SDL_CreateSurface(w, h, PixelFormat);
            }

            if(!pDrawControlsSurface)
                return;

            if(pDrawControlsTexture || FirstRun)
            {
                if(pDrawControlsTexture)
                    SDL_DestroyTexture(pDrawControlsTexture);
                pDrawControlsTexture = SDL_CreateTexture(pWindowRenderer, PixelFormat,
                SDL_TEXTUREACCESS_STREAMING, w, h);
            }

            if(!pDrawControlsTexture)
                return;
            
            SDL_SetTextureBlendMode(pDrawControlsTexture, SDL_BLENDMODE_BLEND);
            SDL_SetTextureScaleMode(pDrawControlsTexture, SDL_SCALEMODE_NEAREST);

            prev_window_w = w;
            prev_window_h = h;
        }

        SDL_ClearSurface(pDrawControlsSurface, 0, 0, 0, 0);

        Uint32 buttoncolor;

        if(GetKeyState(KEY_INPUT_LEFT))
            buttoncolor = SDL_MapSurfaceRGBA(pDrawControlsSurface, 150, 150, 150, 100);
        else
            buttoncolor = SDL_MapSurfaceRGBA(pDrawControlsSurface, 255, 255, 255, 100);
        SDL_FillSurfaceRect(pDrawControlsSurface, &LeftButton, buttoncolor);
        
        if(GetKeyState(KEY_INPUT_RIGHT))
            buttoncolor = SDL_MapSurfaceRGBA(pDrawControlsSurface, 150, 150, 150, 100);
        else
            buttoncolor = SDL_MapSurfaceRGBA(pDrawControlsSurface, 255, 255, 255, 100);
        SDL_FillSurfaceRect(pDrawControlsSurface, &RightButton, buttoncolor);

        if(GetKeyState(KEY_INPUT_DOWN))
            buttoncolor = SDL_MapSurfaceRGBA(pDrawControlsSurface, 150, 150, 150, 100);
        else
            buttoncolor = SDL_MapSurfaceRGBA(pDrawControlsSurface, 255, 255, 255, 100);
        SDL_FillSurfaceRect(pDrawControlsSurface, &DownButton, buttoncolor);

        if(GetKeyState(KEY_INPUT_UP))
            buttoncolor = SDL_MapSurfaceRGBA(pDrawControlsSurface, 150, 150, 150, 100);
        else
            buttoncolor = SDL_MapSurfaceRGBA(pDrawControlsSurface, 255, 255, 255, 100);
        SDL_FillSurfaceRect(pDrawControlsSurface, &UpButton, buttoncolor);

        if(GetKeyState(KEY_INPUT_Z))
            buttoncolor = SDL_MapSurfaceRGBA(pDrawControlsSurface, 150, 150, 150, 100);
        else
            buttoncolor = SDL_MapSurfaceRGBA(pDrawControlsSurface, 255, 255, 255, 100);
        SDL_FillSurfaceRect(pDrawControlsSurface, &JumpButton, buttoncolor);

        if(GetKeyState(KEY_INPUT_ESCAPE))
            buttoncolor = SDL_MapSurfaceRGBA(pDrawControlsSurface, 150, 150, 150, 100);
        else
            buttoncolor = SDL_MapSurfaceRGBA(pDrawControlsSurface, 255, 255, 255, 100);
        SDL_FillSurfaceRect(pDrawControlsSurface, &PauseButton, buttoncolor);

        buttoncolor = SDL_MapSurfaceRGBA(pDrawControlsSurface, 0, 0, 0, 100);

        //MOAHAHAHAHAHAA
        #define SyobonKZEvilRectangleColor(surface, rect, color) \
        {   \
            SDL_Rect tempthing = rect;  \
            tempthing.w = 1;    \
            SDL_FillSurfaceRect(surface, &tempthing, color);    \
            tempthing.x += rect.w - 1;  \
            SDL_FillSurfaceRect(surface, &tempthing, color);    \
            tempthing.x = rect.x;   \
            tempthing.w = rect.w;   \
            \
            tempthing.h = 1;    \
            SDL_FillSurfaceRect(surface, &tempthing, color);    \
            tempthing.y += rect.h - 1;  \
            SDL_FillSurfaceRect(surface, &tempthing, color);    \
        }

        //Normal buttons
        SyobonKZEvilRectangleColor(pDrawControlsSurface, LeftButton, buttoncolor);
        SyobonKZEvilRectangleColor(pDrawControlsSurface, RightButton, buttoncolor);
        SyobonKZEvilRectangleColor(pDrawControlsSurface, DownButton, buttoncolor);
        SyobonKZEvilRectangleColor(pDrawControlsSurface, UpButton, buttoncolor);
        SyobonKZEvilRectangleColor(pDrawControlsSurface, JumpButton, buttoncolor);

        //Pause button
        SyobonKZEvilRectangleColor(pDrawControlsSurface, PauseButton, buttoncolor);
        buttoncolor = SDL_MapSurfaceRGBA(pDrawControlsSurface, 100, 100, 100, 100);
        SDL_Rect Decoration = {(PauseButton.x + PauseButton.w / 3) - (PauseButton.w / 6 + (PauseButton.w / 12)), PauseButton.y + PauseButton.h / 6, PauseButton.w / 3, (PauseButton.h / 3) * 2};
        SDL_FillSurfaceRect(pDrawControlsSurface, &Decoration, buttoncolor);
        Decoration.x = (PauseButton.x + ((PauseButton.w / 3) * 2) - (PauseButton.w / 6)) + (PauseButton.w / 12);
        SDL_FillSurfaceRect(pDrawControlsSurface, &Decoration, buttoncolor);

        SDL_UpdateTexture(pDrawControlsTexture, nullptr, pDrawControlsSurface->pixels, pDrawControlsSurface->pitch);
        SDL_RenderTexture(pWindowRenderer, pDrawControlsTexture, nullptr, nullptr);

        FirstRun = false;
    }

    #endif

void MainLoop()
{
    while (ProcessMessage() == 0)
    {
        #ifdef __ANDROID__
            UpdateTouchControls();
            HandleTouchInput();
        #endif
        UpdateKeys();
        SyobonQuit = 0;
        Mainprogram();
        if (SyobonQuit == 3)
            break;
    }
}

byte WaitKey()
{
    SDL_Event event;
    while (true)
    {
        while (SDL_PollEvent(&event))
            if (event.type == SYOBONKZ_EVENT_KEYDOWN
            #ifdef __ANDROID__
            || event.type == SDL_EVENT_FINGER_DOWN
            #endif
            )
                return SYOBONKZ_KEY_EVENT_SDL_ALIAS;
    }
}

#endif

void UpdateKeys()
{
    SDL_Event event;
    while (SDL_PollEvent(&event))
    {
        switch (event.type)
        {
        case SYOBONKZ_EVENT_KEYDOWN:
            SetKeyState(SYOBONKZ_KEY_EVENT_SDL_ALIAS, true);
            break;
        case SYOBONKZ_EVENT_KEYUP:
            SetKeyState(SYOBONKZ_KEY_EVENT_SDL_ALIAS, false);
            break;
        case SYOBONKZ_EVENT_JOYAXISMOTION:
            if (event.jaxis.which == 0)
            {
                if (event.jaxis.axis == JOYSTICK_XAXIS)
                {
                    if (event.jaxis.value < 0)
                        SetKeyState(SDLK_LEFT, true);
                    else if (event.jaxis.value > 0)
                        SetKeyState(SDLK_RIGHT, true);
                    else
                    {
                        SetKeyState(SDLK_LEFT, false);
                        SetKeyState(SDLK_RIGHT, false);
                    }
                }
                else if (event.jaxis.axis == JOYSTICK_YAXIS)
                {
                    if (event.jaxis.value < 0)
                        SetKeyState(SDLK_UP, true);
                    else if (event.jaxis.value > 0)
                        SetKeyState(SDLK_DOWN, true);
                    else
                    {
                        SetKeyState(SDLK_UP, false);
                        SetKeyState(SDLK_DOWN, false);
                    }
                }
            }
            break;
        case SYOBONKZ_EVENT_QUIT:
            DxLibExit = true;
            break;
        }
    }
}

const char *GetSavePath()
{
    #ifdef SYOBONKZ_USE_SDL3
        return SDL_GetPrefPath("m0rekz.github.io","SyobonKZ");
    #else
        return nullptr;
    #endif
}