initial push

2026-05-29 03:37:25 +02:00
commit b78359dc02
3 changed files with 8172 additions and 0 deletions
@@ -0,0 +1,165 @@
+#include <stdio.h>
+#include <unistd.h>
+#include <SDL3/SDL.h>
+#include <SDL3/SDL_video.h>
+#include <SDL3/SDL_mouse.h>
+#include <SDL3/SDL_keyboard.h>
+#include <SDL3/SDL_events.h>
+#include <math.h>
+
+#define STB_IMAGE_IMPLEMENTATION
+#include "stb_image.h"
+
+#define DESIRED_IMAGE_CHANNELS 4
+
+typedef struct Image{
+    int x;
+    int y;
+    int channels;
+    unsigned char* pixels;
+} Image;
+
+Image load_image(const char* filepath){
+    Image image;
+    image.pixels = stbi_load(filepath, &image.x, &image.y, &image.channels, DESIRED_IMAGE_CHANNELS);
+    return image;
+}
+
+void free_image(Image* image){
+    if(image->pixels) stbi_image_free(image->pixels);
+}
+
+SDL_Window* create_window(const char* title, int w, int h){
+    const SDL_InitFlags init_flags = SDL_INIT_VIDEO | SDL_INIT_EVENTS;
+    const SDL_WindowFlags window_flags =  SDL_WINDOW_BORDERLESS
+                                        // | SDL_WINDOW_MAXIMIZED 
+                                        // | SDL_WINDOW_TRANSPARENT 
+                                        // | SDL_WINDOW_ALWAYS_ON_TOP 
+                                        | SDL_WINDOW_RESIZABLE
+                                        | SDL_WINDOW_KEYBOARD_GRABBED;
+
+    SDL_Init(init_flags);
+
+    /* Used when a larger window is wanted, image displaying is dynamically calculated
+    int display_count;
+    SDL_DisplayID* displays = SDL_GetDisplays(&display_count);
+    if(display_count == 0){
+        printf("%s\n", SDL_GetError());
+        printf("Could not get any displays!");
+        exit(5);
+    }
+
+    const SDL_DisplayMode* mode = SDL_GetDesktopDisplayMode(displays[0]);
+    if(!mode){
+        printf("Failed to get display information!");
+        exit(6);
+    }
+    */
+
+    SDL_Window* window = SDL_CreateWindow(title, w, h, window_flags);
+    SDL_SetWindowAspectRatio(window, (float)w / (float)h, (float)w / (float)h);
+
+    return window;
+}
+
+SDL_Surface* get_surface_from_window(SDL_Window* window){
+    return SDL_GetWindowSurface(window);
+}
+
+void draw_image(SDL_Surface* surface, Image* image){
+    SDL_Rect pixel = { 0, 0, 1, 1 };
+    
+    int center_x = ((surface->w + 1) / 2 - 1);
+    int center_y = ((surface->h + 1) / 2 - 1);
+
+    int dst_x = center_x - image->x / 2;
+    int dst_y = center_y - image->y / 2;
+
+    for(int x = 0; x < image->x; x++){
+        pixel.x = dst_x + x;
+        for(int y = 0; y < image->y; y++){
+            pixel.y = dst_y + y;
+            const int current_pixel_idx = (y * image->x + x) * DESIRED_IMAGE_CHANNELS;
+
+            Uint32 color = SDL_MapSurfaceRGBA(surface,
+                                            image->pixels[current_pixel_idx + 0],
+                                            image->pixels[current_pixel_idx + 1],
+                                            image->pixels[current_pixel_idx + 2],
+                                            image->pixels[current_pixel_idx + 3]);
+
+            SDL_FillSurfaceRect(surface, &pixel, color);
+        }
+    }
+}
+
+int main(int argc, char** argv){
+    if(argc < 2){
+        printf("Usage: %s [image filepath]\n", argv[0]);
+        exit(1);
+    }
+
+    const char* filepath = argv[1];
+
+    if(access(filepath, F_OK) != 0){
+        printf("File does not exist!\n");
+        exit(2);
+    }
+
+    Image image = load_image(filepath);
+    if(image.pixels == NULL){
+        printf("Failed to load image!");
+        exit(3);
+    }
+
+    printf("Dimensions: Width = %d, Height = %d\n", image.x, image.y);
+
+    SDL_Window* window = create_window("SimpleImageViewer", image.x, image.y);
+    if(!window){
+        printf("Failed to create window!");
+        exit(4);
+    }
+
+    SDL_Surface* surface = get_surface_from_window(window);
+    if(!surface){
+        printf("Failed to get surface!");
+        exit(5);
+    }
+
+    draw_image(surface, &image);
+
+    free_image(&image);
+
+    SDL_UpdateWindowSurface(window);
+
+    bool drag_mouse = false;
+    int last_pointer_x = 0;
+    int last_pointer_y = 0;
+
+    SDL_Event event;
+    bool run = true;
+    while(run){
+        while (SDL_PollEvent(&event)) {
+            if (event.type == SDL_EVENT_KEY_UP){
+                switch(event.key.key){
+                    case SDLK_ESCAPE: case SDLK_SPACE: case SDLK_RETURN:
+                        run = false;
+                        break;
+                }
+            }
+            if(event.type == SDL_EVENT_QUIT) run = false;
+            if(event.type == SDL_EVENT_MOUSE_BUTTON_DOWN && event.button.button == SDL_BUTTON_LEFT){
+                drag_mouse = true;
+                last_pointer_x = event.motion.x;
+                last_pointer_y = event.motion.y;
+            }
+            if(event.type == SDL_EVENT_MOUSE_BUTTON_UP && event.button.button == SDL_BUTTON_LEFT) drag_mouse = false;
+            if(event.type == SDL_EVENT_MOUSE_MOTION && drag_mouse){
+                int last_x, last_y;
+                SDL_GetWindowPosition(window, &last_x, &last_y);
+                SDL_SetWindowPosition(window, last_x + (int)event.motion.x - last_pointer_x, last_y + (int)event.motion.y - last_pointer_y);
+            }
+        }
+    }
+
+    SDL_DestroyWindow(window);
+}