trying to debug, additional rewrites

platform/sdl/BGraph2.cpp

@@ -0,0 +1,112 @@
+#include "BGraph2.h"
+
+#include "sdl_context.h"
+#include "global_context.h"
+
+
+static std::unique_ptr<uint16_t[]> screen_buffer;
+static std::unique_ptr<uint16_t[]> buffer2nd;
+static uint16_t *render_target;
+static uint16_t screen_pitch = 640;
+
+char DXInit64(char inwindow,int zoom,int monitor, int refresh) {
+
+    SDLContext::DisplayMode mode;
+    if (inwindow) {
+        if (zoom) {
+            mode = SDLContext::double_window;
+        } else {
+            mode = SDLContext::native_window;
+        }
+    } else {
+        mode = SDLContext::fullscreen;
+    }
+
+    screen_pitch = 640;
+    get_sdl_global_context().init_screen(mode, "Skeldal"); //todo allow change
+    screen_buffer = std::make_unique<uint16_t[]>(screen_pitch*480);
+    buffer2nd = std::make_unique<uint16_t[]>(screen_pitch*480);
+    render_target = screen_buffer.get();
+
+    return 0;
+}
+
+void DXCloseMode() {
+    get_sdl_global_context().close_screen();
+}
+
+
+uint16_t *GetScreenAdr() {
+    return render_target;
+}
+uint16_t *GetBuffer2nd() {
+    return buffer2nd.get();
+
+}
+int32_t GetScreenPitch() {
+    return screen_pitch;
+}
+int32_t GetBuffer2ndPitch() {
+    return screen_pitch;
+}
+int32_t GetScreenSizeBytes() {
+    return screen_pitch * 480 * 2;
+}
+
+void RedirectScreen(uint16_t *newaddr) {
+    render_target = newaddr;
+}
+void RestoreScreen() {
+    render_target = screen_buffer.get();
+}
+void RedirectScreenBufferSecond() {
+    render_target = buffer2nd.get();
+}
+int DxGetResX() {
+    return 640;
+}
+int DxGetResY() {
+    return 480;
+}
+void setvesa_displaystart(int x,int y){
+
+}
+void StripBlt(void *data, unsigned int startline, uint32_t width) {
+
+    unsigned short *start=startline*GetScreenPitch()+GetScreenAdr();
+    while (width--)
+    {
+      memcpy(start,data,640*2);
+      data=(void *)(reinterpret_cast<char *>(data)+get_sdl_global_context().get_surface_pitch());
+      start=start+GetScreenPitch();
+    }
+
+}
+
+void DXCopyRects64(unsigned short x,unsigned short y,unsigned short xs,unsigned short ys) {
+    get_sdl_global_context().present_rect(screen_buffer.get(), screen_pitch, x,y,xs,ys);
+
+}
+
+void *DxPrepareWalk(int ypos) {
+    return 0;
+}
+void DxZoomWalk(void *handle, int ypos, int *points,float phase, void *lodka) {
+
+}
+void DxDoneWalk(void *handle) {
+
+}
+
+void *DxPrepareTurn(int ypos) {
+    return 0;
+}
+void DxTurn(void *handle, char right, int ypos,int border, float phase, void *lodka) {
+
+}
+void DxDoneTurn(void *handle) {
+
+}
+void DxTurnLeftRight(char right, float phase, int border, int ypos, int *last) {
+
+}

platform/sdl/BGraph2.h

@@ -0,0 +1,63 @@
+#include <stdint.h>
+
+#ifndef __BGRAPH_DX_WRAPPER_
+#define __BGRAPH_DX_WRAPPER_
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+uint16_t *GetScreenAdr();
+uint16_t *GetBuffer2nd();
+int32_t GetScreenPitch();
+int32_t GetBuffer2ndPitch();
+int32_t GetScreenSizeBytes();
+
+void RedirectScreen(uint16_t *newaddr);
+void RestoreScreen();
+void RedirectScreenBufferSecond();
+
+
+//inicializuje a otevira rezim 640x480x16b v DX - otevre okno, pripravi vse pro beh hry
+//Vraci 1 pri uspechu
+char DXInit64(char inwindow,int zoom,int monitor, int refresh);
+
+//uzavre rezim grafiky
+void DXCloseMode();
+
+//void DXCopyRects32(unsigned short x,unsigned short y,unsigned short xs,unsigned short ys);
+void DXCopyRects64(unsigned short x,unsigned short y,unsigned short xs,unsigned short ys);
+
+void *DxPrepareWalk(int ypos);
+void DxZoomWalk(void *handle, int ypos, int *points,float phase, void *lodka);
+void DxDoneWalk(void *handle);
+
+void *DxPrepareTurn(int ypos);
+void DxTurn(void *handle, char right, int ypos,int border, float phase, void *lodka);
+void DxDoneTurn(void *handle);
+void DxTurnLeftRight(char right, float phase, int border, int ypos, int *last);
+
+
+void DxDialogs(char enable);
+
+void setvesa_displaystart(int x,int y);
+
+
+void DxSetInitResolution(int x, int y);
+int DxGetResX();
+int DxGetResY();
+
+void DXMouseTransform(unsigned short *x, unsigned short *y);
+
+//HWND GetGameWindow();
+//void DxLockBuffers(BOOL lock);
+
+void StripBlt(void *data, unsigned int startline, uint32_t width);
+
+
+#ifdef __cplusplus
+  }
+#endif
+
+
+#endif

platform/sdl/CMakeLists.txt

@@ -1 +1,3 @@
 add_subdirectory(tests)
+
+add_library(skeldal_sdl sdl_context.cpp BGraph2.cpp input.cpp sound.cpp)

platform/sdl/global_context.h

@@ -0,0 +1,11 @@
+#pragma once
+
+#include "sdl_context.h"
+
+inline SDLContext &get_sdl_global_context () {
+    static SDLContext sdl_global_context;
+    return sdl_global_context;
+}
+
+
+

platform/sdl/input.cpp

@@ -0,0 +1,28 @@
+#include "global_context.h"
+#include "input.h"
+
+char get_control_key_state() {
+    return 0;   //todo
+}
+char get_shift_key_state() {
+    return 0;   //todo
+}
+uint32_t _bios_keybrd(int mode) {
+    return 0;
+}
+
+void SetWheelMapping(char up, char down) { //todo
+
+}
+
+static MS_EVENT ms_event  = {};
+
+
+
+void get_ms_event(MS_EVENT *event) {
+    *event = ms_event;
+}
+
+void ShareCPU() {
+
+}

platform/sdl/input.h

@@ -0,0 +1,31 @@
+/*
+ * input.h
+ *
+ *  Created on: 26. 1. 2025
+ *      Author: ondra
+ */
+
+#ifndef PLATFORM_SDL_INPUT_H_
+#define PLATFORM_SDL_INPUT_H_
+
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <devices.h>
+
+
+char get_control_key_state();
+char get_shift_key_state();
+uint32_t _bios_keybrd(int mode);
+void SetWheelMapping(char up, char down);
+void get_ms_event(MS_EVENT *event);
+void ShareCPU();
+
+#ifdef __cplusplus
+}
+#endif
+
+
+#endif /* PLATFORM_SDL_INPUT_H_ */

platform/sdl/sdl_context.cpp

@@ -0,0 +1,186 @@
+#include "sdl_context.h"
+#include "../platform.h"
+
+#include <stdexcept>
+void SDLContext::SDL_Deleter::operator ()(SDL_Window* window) {
+    SDL_DestroyWindow(window);
+}
+
+void SDLContext::SDL_Deleter::operator ()(SDL_Renderer* renderer) {
+    SDL_DestroyRenderer(renderer);
+}
+
+void SDLContext::SDL_Deleter::operator ()(SDL_Surface* surface) {
+    SDL_FreeSurface(surface);
+}
+
+void SDLContext::SDL_Deleter::operator ()(SDL_Texture* texture) {
+    SDL_DestroyTexture(texture);
+}
+
+struct SDL_INIT_Context {
+
+    SDL_INIT_Context() {
+        if (SDL_Init(SDL_INIT_VIDEO|SDL_INIT_TIMER|SDL_INIT_AUDIO) < 0) {
+            SDL_Log("Unable to initialize SDL: %s", SDL_GetError());
+            exit(1);
+        }
+        inited = true;
+    }
+    ~SDL_INIT_Context() {
+        SDL_Quit();
+    }
+
+
+    bool inited = false;
+};
+
+static SDL_INIT_Context init_context = {};
+
+SDLContext::SDLContext() {
+    if (!init_context.inited) throw std::runtime_error("SDL not inited");
+
+}
+
+void SDLContext::init_screen(DisplayMode mode, const char *title) {
+    char buff[256];
+
+    int width = 640;
+    int height = 480;
+    if (mode == double_window) {
+        width*=2;
+        height*=2;
+    }
+    SDL_Window *window = SDL_CreateWindow(title,
+                SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED,
+                width, height, SDL_WINDOW_RESIZABLE|(mode==fullscreen?SDL_WINDOW_FULLSCREEN_DESKTOP:0));
+
+    if (!window) {
+        snprintf(buff, sizeof(buff), "SDL Error create window: %s\n", SDL_GetError());
+        throw std::runtime_error(buff);
+    }
+
+    _window.reset(window);
+    SDL_Renderer *renderer = SDL_CreateRenderer(_window.get(), -1, 0);
+    if (!renderer) {
+        snprintf(buff,sizeof(buff), "Chyba při vytváření rendereru: %s\n", SDL_GetError());
+        throw std::runtime_error(buff);
+    }
+    _renderer.reset(renderer);
+    // Vytvoření softwarového backbufferu (surface)
+    SDL_Surface *backbuffer = SDL_CreateRGBSurfaceWithFormat(0, 640, 480, 16, SDL_PIXELFORMAT_RGB565);
+    if (!backbuffer) {
+        snprintf(buff,sizeof(buff), "Chyba při vytváření surface: %s\n", SDL_GetError());
+        throw std::runtime_error(buff);
+    }
+    _surface.reset(backbuffer);
+    // Vytvoření textury pro zobrazení backbufferu
+    SDL_Texture *texture = SDL_CreateTexture(renderer, SDL_PIXELFORMAT_RGB565, SDL_TEXTUREACCESS_STREAMING, 640, 480);
+    if (!texture) {
+        snprintf(buff, sizeof(buff), "Chyba při vytváření textury: %s\n", SDL_GetError());
+        throw std::runtime_error(buff);
+    }
+    _texture.reset(texture);
+
+    SDL_LockSurface(_surface.get());
+
+    if (!_timer_event) _timer_event = SDL_RegisterEvents(1);
+    _fullscreen_mode = mode == fullscreen;
+}
+
+void SDLContext::close_screen() {
+    SDL_UnlockSurface(_surface.get());
+    _texture.reset();
+    _surface.reset();
+    _renderer.reset();
+    _window.reset();
+
+}
+
+uint16_t* SDLContext::get_surface_addr() {
+    return reinterpret_cast<uint16_t *>(_surface->pixels);
+}
+
+
+int32_t SDLContext::get_surface_pitch() {
+    return _surface->pitch;
+}
+
+
+void  SDLContext::charge_timer() {
+    _active_timer = SDL_AddTimer(1000/TIMERSPEED, [](Uint32 interval, void *param) -> Uint32 {
+        SDLContext *me = reinterpret_cast<SDLContext *>(param);
+        SDL_Event* event = (SDL_Event*)param;
+          event->type = me->_timer_event;
+          SDL_PushEvent(event);
+          return 0;
+    }, this);
+
+}
+void SDLContext::pool_events() {
+    if (!_active_timer.has_value()) charge_timer();
+    SDL_Event e;
+    while (true) {
+       if (SDL_WaitEvent(&e)) {
+           if (e.type == SDL_QUIT) {
+               _quit_requested = true;
+               return;
+           }
+           if (e.type == _timer_event) {
+               break;
+           }
+           if (e.type == SDL_KEYDOWN) {
+               if (e.key.keysym.sym == SDLK_RETURN && (e.key.keysym.mod & KMOD_ALT)) {
+                   _fullscreen_mode = !_fullscreen_mode;
+                   SDL_SetWindowFullscreen(_window.get(), _fullscreen_mode ? SDL_WINDOW_FULLSCREEN_DESKTOP : 0);
+               }
+           } else if (e.type == SDL_MOUSEMOTION) {
+               int mouseX = e.motion.x;
+               int mouseY = e.motion.y;
+               int windowWidth;
+               int windowHeight;
+               SDL_GetWindowSize(_window.get(), &windowWidth, &windowHeight);
+               float normalizedX = (float)mouseX / windowWidth;
+               float normalizedY = (float)mouseY / windowHeight;
+               ms_event.event = 1;
+               ms_event.event_type = 1;
+               ms_event.x = (int16_t)(640*normalizedX);
+               ms_event.y = (int16_t)(480*normalizedY);
+           } else if (e.type == SDL_MOUSEBUTTONDOWN || e.type == SDL_MOUSEBUTTONUP) {
+               int mouseX = e.button.x;
+               int mouseY = e.button.y;
+               int button = e.button.button;
+               int up =  e.type == SDL_MOUSEBUTTONUP?1:0;
+               ms_event.event = 1;
+               ms_event.event_type = (1<<(2*button-1+up));
+               switch (button) {
+                   default: break;
+                   case 1: ms_event.tl1 = !up; break;
+                   case 2: ms_event.tl2 = !up; break;
+                   case 3: ms_event.tl3 = !up; break;
+               }
+           }
+
+       } else {
+           throw std::runtime_error("SDL_WaitEvent error");
+       }
+    }
+    charge_timer();
+
+}
+
+void SDLContext::present_rect(uint16_t *pixels, unsigned int pitch,
+        unsigned int x, unsigned int y, unsigned int xs, unsigned ys) {
+
+    auto beg = pixels + y * pitch + y;
+    SDL_Rect r = {static_cast<int>(x),
+                  static_cast<int>(y),
+                  static_cast<int>(xs),
+                  static_cast<int>(ys)};
+    SDL_UpdateTexture(_texture.get(), &r, beg, pitch*2);
+    SDL_RenderClear(_renderer.get());
+    SDL_RenderCopy(_renderer.get(), _texture.get(), NULL, NULL);
+    SDL_RenderPresent(_renderer.get());
+
+
+}

platform/sdl/sdl_context.h

@@ -0,0 +1,55 @@
+#pragma once
+
+#include <memory>
+#include <optional>
+#include <SDL2/SDL.h>
+#include <mouse.h>
+
+class SDLContext {
+public:
+
+    SDLContext();
+
+    enum DisplayMode {
+        native_window,
+        double_window,
+        fullscreen
+    };
+
+
+    void init_screen(DisplayMode mode, const char *title);
+
+    void close_screen();
+
+
+    uint16_t *get_surface_addr();
+    int32_t get_surface_pitch();
+
+
+    void pool_events();
+
+    void present_rect(uint16_t *pixels, unsigned int pitch, unsigned int x, unsigned int y, unsigned int xs,unsigned ys);
+
+protected:
+
+    struct SDL_Deleter {
+        void operator()(SDL_Window *);
+        void operator()(SDL_Renderer *);
+        void operator()(SDL_Surface *);
+        void operator()(SDL_Texture *);
+    };
+
+    MS_EVENT ms_event;
+
+    std::unique_ptr<SDL_Window, SDL_Deleter> _window;
+    std::unique_ptr<SDL_Renderer, SDL_Deleter> _renderer;
+    std::unique_ptr<SDL_Surface, SDL_Deleter> _surface;
+    std::unique_ptr<SDL_Texture, SDL_Deleter> _texture;
+
+    std::optional<SDL_TimerID> _active_timer;
+    Uint32 _timer_event = 0;
+
+    bool _quit_requested = false;
+    bool _fullscreen_mode = false;
+    void charge_timer();
+};

platform/sdl/sound.cpp

@@ -0,0 +1,78 @@
+#include "../platform.h"
+#include <zvuk.h>
+
+void set_mixing_device(int mix_dev,int mix_freq,...) {
+
+}
+char start_mixing() {
+    return 0;
+}
+void stop_mixing() {
+
+}
+void play_sample(int channel,void *sample,int32_t size,int32_t lstart,int32_t sfreq,int type) {
+
+}
+void set_channel_volume(int channel,int left,int right) {
+
+}
+void set_end_of_song_callback(const char * (*cb)(void *), void *ctx) {
+
+}
+
+void fade_music() {
+
+}
+int mix_back_sound(int synchro) {
+    return 0;
+}
+
+//int open_backsound(char *filename);
+void change_music(const char *filename) {
+
+}
+
+//char *device_name(int device);
+//void force_music_volume(int volume);
+
+//void set_backsnd_freq(int freq);
+
+char get_channel_state(int channel) {
+    return 0;
+}
+void get_channel_volume(int channel,int *left,int *right) {
+
+}
+void mute_channel(int channel) {
+
+}
+void chan_break_loop(int channel) {
+
+}
+void chan_break_ext(int channel,void *org_sample,int32_t size_sample) {
+
+}
+
+char set_snd_effect(int funct,int data) {
+    return 0;
+}
+char check_snd_effect(int funct) {
+    return 0;
+}
+int  get_snd_effect(int funct) {
+    return 0;
+}
+
+void *PrepareVideoSound(int mixfreq, int buffsize) {
+    return 0;
+}
+char LoadNextVideoFrame(void *buffer, char *data, int size, short *xlat, short *accnums, int32_t *writepos) {
+    return 0;
+
+}
+void DoneVideoSound(void *buffer) {
+
+}
+
+
+

platform/sdl/sound.h

@@ -0,0 +1,15 @@
+/*
+ * sound.h
+ *
+ *  Created on: 26. 1. 2025
+ *      Author: ondra
+ */
+
+#ifndef PLATFORM_SDL_SOUND_H_
+#define PLATFORM_SDL_SOUND_H_
+
+
+
+
+
+#endif /* PLATFORM_SDL_SOUND_H_ */

platform/sdl/tests/CMakeLists.txt

@@ -1,6 +1,8 @@
 set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/tests/)
 
-set(testFiles sdl_minimal_test.cpp sdl_surface_test.cpp
+set(testFiles sdl_minimal_test.cpp sdl_surface_test.cpp 
+    sdl_mouse.cpp
+    sdl_update_texture.cpp
               )
 
 foreach (testFile ${testFiles})

platform/sdl/tests/sdl_mouse.cpp

@@ -0,0 +1,79 @@
+#include <SDL2/SDL.h>
+#include <iostream>
+
+int main(int argc, char* argv[]) {
+    if (SDL_Init(SDL_INIT_VIDEO) != 0) {
+        std::cerr << "SDL_Init Error: " << SDL_GetError() << std::endl;
+        return 1;
+    }
+
+    SDL_Window* window = SDL_CreateWindow("SDL Mouse Event Example", SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, 800, 600, SDL_WINDOW_RESIZABLE);
+    if (!window) {
+        std::cerr << "SDL_CreateWindow Error: " << SDL_GetError() << std::endl;
+        SDL_Quit();
+        return 1;
+    }
+
+    SDL_Renderer* renderer = SDL_CreateRenderer(window, -1, SDL_RENDERER_ACCELERATED);
+    if (!renderer) {
+        std::cerr << "SDL_CreateRenderer Error: " << SDL_GetError() << std::endl;
+        SDL_DestroyWindow(window);
+        SDL_Quit();
+        return 1;
+    }
+
+    SDL_Event e;
+    bool quit = false;
+    int isFullscreen = 0;
+
+    while (!quit) {
+        while (SDL_PollEvent(&e)) {
+            if (e.type == SDL_QUIT) {
+                quit = true;
+            } else if (e.type == SDL_MOUSEMOTION) {
+                // Získání souřadnic myši
+                int mouseX = e.motion.x, mouseY = e.motion.y;
+
+                // Přepočet souřadnic na poměr vůči rozměrům okna
+                int windowWidth, windowHeight;
+                SDL_GetWindowSize(window, &windowWidth, &windowHeight);
+
+                float normalizedX = (float)mouseX / windowWidth;
+                float normalizedY = (float)mouseY / windowHeight;
+
+                std::cout << "Mouse moved to: (" << mouseX << ", " << mouseY << ") -> Normalized: ("
+                          << normalizedX << ", " << normalizedY << ")" << std::endl;
+            } else if (e.type == SDL_MOUSEBUTTONDOWN || e.type == SDL_MOUSEBUTTONUP) {
+                int mouseX = e.button.x, mouseY = e.button.y;
+                int button = e.button.button;
+
+                if (e.type == SDL_MOUSEBUTTONDOWN) {
+                    std::cout << "Mouse button pressed at: (" << mouseX << ", " << mouseY << ") button " << button << std::endl;
+                } else {
+                    std::cout << "Mouse button released at: (" << mouseX << ", " << mouseY << ") button " << button << std::endl;
+                }
+            } else if (e.type == SDL_MOUSEWHEEL) {
+                if (e.wheel.y > 0) {
+                    std::cout << "Mouse wheel scrolled up." << std::endl;
+                } else if (e.wheel.y < 0) {
+                    std::cout << "Mouse wheel scrolled down." << std::endl;
+                }
+            } else  if (e.type == SDL_KEYDOWN) {
+                if (e.key.keysym.sym == SDLK_RETURN && (e.key.keysym.mod & KMOD_ALT)) {
+                    // Přepnutí mezi fullscreen a oknem
+                    isFullscreen = !isFullscreen;
+                    SDL_SetWindowFullscreen(window, isFullscreen ? SDL_WINDOW_FULLSCREEN_DESKTOP : 0);
+                }
+            }
+        }
+
+        // Renderování a další logika hry
+        SDL_RenderClear(renderer);
+        SDL_RenderPresent(renderer);
+    }
+
+    SDL_DestroyRenderer(renderer);
+    SDL_DestroyWindow(window);
+    SDL_Quit();
+    return 0;
+}

platform/sdl/tests/sdl_surface_test.cpp

@@ -4,7 +4,7 @@
 
 #define WIDTH 640
 #define HEIGHT 480
-
+#define PITCH 1024  // Pro optimalizaci paměti (pitch může být širší než WIDTH)
 
 int main(int argc, char *argv[]) {
     // Inicializace SDL
@@ -14,14 +14,14 @@ int main(int argc, char *argv[]) {
     }
 
     // Vytvoření SDL okna
-    SDL_Window *window = SDL_CreateWindow("DOS Game Port", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, WIDTH, HEIGHT, 0);
+    SDL_Window *window = SDL_CreateWindow("DOS Game Port", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, WIDTH, HEIGHT, SDL_WINDOW_RESIZABLE);
     if (!window) {
         fprintf(stderr, "Chyba při vytváření okna: %s\n", SDL_GetError());
         SDL_Quit();
         return 1;
     }
 
-    // Vytvoření rendereru (pouze pro zobrazení)
+    // Vytvoření SDL rendereru
     SDL_Renderer *renderer = SDL_CreateRenderer(window, -1, SDL_RENDERER_ACCELERATED);
     if (!renderer) {
         fprintf(stderr, "Chyba při vytváření rendereru: %s\n", SDL_GetError());
@@ -30,9 +30,9 @@ int main(int argc, char *argv[]) {
         return 1;
     }
 
-    // Vytvoření SDL Surface (backbuffer)
-    SDL_Texture *texture = SDL_CreateTexture(renderer, SDL_PIXELFORMAT_RGB565,SDL_TEXTUREACCESS_STREAMING, WIDTH, HEIGHT);
-    if (!texture) {
+    // Vytvoření softwarového backbufferu (surface)
+    SDL_Surface *backbuffer = SDL_CreateRGBSurfaceWithFormat(0, PITCH, HEIGHT, 16, SDL_PIXELFORMAT_RGB565);
+    if (!backbuffer) {
         fprintf(stderr, "Chyba při vytváření surface: %s\n", SDL_GetError());
         SDL_DestroyRenderer(renderer);
         SDL_DestroyWindow(window);
@@ -40,31 +40,56 @@ int main(int argc, char *argv[]) {
         return 1;
     }
 
-    void *raw_pixels;
-    int pitch;
-    SDL_LockTexture(texture, NULL, &raw_pixels, &pitch);
-    // Přímý přístup do paměti surface
-    Uint16 *pixels = reinterpret_cast<Uint16 *>(raw_pixels);
-    printf("Adresa pixelů: %p, pitch: %d bajtů\n", (void *)pixels, pitch);
-
-    // Software rendering - příklad kreslení do paměti
-    for (int y = 0; y < HEIGHT; y++) {
-        for (int x = 0; x < WIDTH; x++) {
-            Uint16 color = (x ^ y) & 0xFFFF; // Příklad barvy
-            pixels[y * (pitch / 2) + x] = color; // Zápis pixelu
-        }
+    // Vytvoření textury pro zobrazení backbufferu
+    SDL_Texture *texture = SDL_CreateTexture(renderer, SDL_PIXELFORMAT_RGB565, SDL_TEXTUREACCESS_STREAMING, WIDTH, HEIGHT);
+    if (!texture) {
+        fprintf(stderr, "Chyba při vytváření textury: %s\n", SDL_GetError());
+        SDL_FreeSurface(backbuffer);
+        SDL_DestroyRenderer(renderer);
+        SDL_DestroyWindow(window);
+        SDL_Quit();
+        return 1;
     }
 
-    SDL_UnlockTexture(texture);
+    // Hlavní smyčka
+    int running = 1;
+    int frame = 0;
+    while (running) {
+        frame++;
+        SDL_Event event;
+        while (SDL_PollEvent(&event)) {
+            if (event.type == SDL_QUIT) {
+                running = 0;
+            }
+        }
 
-    SDL_RenderClear(renderer);
-    SDL_RenderCopy(renderer, texture, NULL, NULL);
-    SDL_RenderPresent(renderer);
+        // Přímý přístup do paměti backbufferu
+        Uint16 *pixels = (Uint16 *)backbuffer->pixels;
+        int pitch = backbuffer->pitch / 2; // Pitch v počtu pixelů (ne bajtů)
 
-    SDL_Delay(3000); // Zobrazení okna na 3 sekundy
+        // Software rendering - příklad (čtení a zápis do backbufferu)
+        for (int y = 0; y < HEIGHT; y++) {
+            for (int x = 0; x < WIDTH; x++) {
+                Uint16 color = (x ^ y ^ frame) & 0xFFFF; // Vzor barvy (testovací)
+                pixels[y * pitch + x] = color;   // Zápis pixelu
+            }
+        }
+
+        // Kopírování backbufferu do textury
+        SDL_UpdateTexture(texture, NULL, backbuffer->pixels, backbuffer->pitch);
+
+        // Vykreslení textury na obrazovku
+        SDL_RenderClear(renderer);
+        SDL_RenderCopy(renderer, texture, NULL, NULL);
+        SDL_RenderPresent(renderer);
+
+        // Zpoždění pro demonstraci (30 FPS)
+        SDL_Delay(1000 / 30);
+    }
 
     // Uvolnění zdrojů
     SDL_DestroyTexture(texture);
+    SDL_FreeSurface(backbuffer);
     SDL_DestroyRenderer(renderer);
     SDL_DestroyWindow(window);
     SDL_Quit();

platform/sdl/tests/sdl_update_texture.cpp

@@ -0,0 +1,91 @@
+#include <SDL2/SDL.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#define WIDTH 640
+#define HEIGHT 480
+#define PITCH 1024  // Pro optimalizaci paměti (pitch může být širší než WIDTH)
+
+int main(int argc, char *argv[]) {
+    // Inicializace SDL
+    if (SDL_Init(SDL_INIT_VIDEO) != 0) {
+        fprintf(stderr, "Chyba při inicializaci SDL: %s\n", SDL_GetError());
+        return 1;
+    }
+
+    // Vytvoření SDL okna
+    SDL_Window *window = SDL_CreateWindow("DOS Game Port", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, WIDTH, HEIGHT, SDL_WINDOW_RESIZABLE);
+    if (!window) {
+        fprintf(stderr, "Chyba při vytváření okna: %s\n", SDL_GetError());
+        SDL_Quit();
+        return 1;
+    }
+
+
+    // Vytvoření SDL rendereru
+    SDL_Renderer *renderer = SDL_CreateRenderer(window, -1, SDL_RENDERER_ACCELERATED);
+    if (!renderer) {
+        fprintf(stderr, "Chyba při vytváření rendereru: %s\n", SDL_GetError());
+        SDL_DestroyWindow(window);
+        SDL_Quit();
+        return 1;
+    }
+
+
+    // Vytvoření textury pro zobrazení backbufferu
+    SDL_Texture *texture = SDL_CreateTexture(renderer, SDL_PIXELFORMAT_RGB565, SDL_TEXTUREACCESS_STREAMING, WIDTH, HEIGHT);
+    if (!texture) {
+        fprintf(stderr, "Chyba při vytváření textury: %s\n", SDL_GetError());
+        SDL_DestroyRenderer(renderer);
+        SDL_DestroyWindow(window);
+        SDL_Quit();
+        return 1;
+    }
+
+    uint16_t *pixels = new uint16_t[HEIGHT*WIDTH];
+    int pitch = WIDTH;
+
+
+    // Hlavní smyčka
+    int running = 1;
+    int frame = 0;
+    while (running) {
+        frame++;
+        SDL_Event event;
+        while (SDL_PollEvent(&event)) {
+            if (event.type == SDL_QUIT) {
+                running = 0;
+            }
+        }
+
+        // Přímý přístup do paměti backbufferu
+
+        // Software rendering - příklad (čtení a zápis do backbufferu)
+        for (int y = 0; y < HEIGHT; y++) {
+            for (int x = 0; x < WIDTH; x++) {
+                Uint16 color = (x ^ y ^ frame) & 0xFFFF; // Vzor barvy (testovací)
+                pixels[y * pitch + x] = color;   // Zápis pixelu
+            }
+        }
+
+        // Kopírování backbufferu do textury
+        SDL_UpdateTexture(texture, NULL, pixels, pitch*2);
+
+        // Vykreslení textury na obrazovku
+        SDL_RenderClear(renderer);
+        SDL_RenderCopy(renderer, texture, NULL, NULL);
+        SDL_RenderPresent(renderer);
+
+        // Zpoždění pro demonstraci (30 FPS)
+        SDL_Delay(1000 / 30);
+    }
+
+    // Uvolnění zdrojů
+    SDL_DestroyTexture(texture);
+    SDL_DestroyRenderer(renderer);
+    SDL_DestroyWindow(window);
+    SDL_Quit();
+    delete [] pixels;
+
+    return 0;
+}