Added basic panning.

src/main.c

@@ -0,0 +1,168 @@
+#include <SDL2/SDL_surface.h>
+#include <stdio.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <string.h>
+#include <SDL2/SDL.h>
+#include <SDL2/SDL_events.h>
+#include <SDL2/SDL_hints.h>
+#include <SDL2/SDL_keycode.h>
+#include <SDL2/SDL_mouse.h>
+#include <SDL2/SDL_pixels.h>
+#include <SDL2/SDL_rect.h>
+#include <SDL2/SDL_render.h>
+#include <SDL2/SDL_stdinc.h>
+#include <SDL2/SDL_thread.h>
+#include <SDL2/SDL_timer.h>
+#include <SDL2/SDL_video.h>
+#include <SDL2/SDL_image.h>
+#include <SDL2/SDL_ttf.h>
+
+const int SCREEN_WIDTH = 1280;
+const int SCREEN_HEIGHT = 720;
+int MouseDown = 0;
+
+typedef struct {
+    SDL_Window *window;
+    SDL_Renderer *renderer;
+    TTF_Font* font;
+} App;
+
+App app;
+
+void HandleInput(void);
+int Exit = 0;
+int XRel, YRel;
+int XOrg, YOrg;
+
+void Cleanup(void) {
+    SDL_DestroyWindow(app.window);
+    SDL_DestroyRenderer(app.renderer);
+    TTF_CloseFont(app.font);
+    TTF_Quit();
+    SDL_Quit();
+}
+
+int main(int argc, char** argv){
+    memset(&app, 0, sizeof(app));
+    XRel = 0;
+    YRel = 0;
+    XOrg = 0;
+    YOrg = 0;
+
+    atexit(Cleanup);
+
+        if (SDL_Init(SDL_INIT_VIDEO) < 0) {
+        printf("SDL failed: %s\n", SDL_GetError());
+        return -1;
+    }
+
+     if (TTF_Init() < 0) {
+        printf("Failed to init TTF: %s\n", TTF_GetError());
+        return -1;
+    }
+
+    app.font = TTF_OpenFont("/usr/share/fonts/TTF/Hack-Regular.ttf", 14);
+
+    if (app.font == NULL) {
+        printf("Failed to load font\n");
+        return -1;
+    }
+
+    app.window = SDL_CreateWindow("SDL Tutorial", SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, SCREEN_WIDTH, SCREEN_HEIGHT, SDL_WINDOW_SHOWN);
+
+    if (app.window == NULL) {
+        printf("Window creation failed: %s\n", SDL_GetError());
+        return -1;
+    }
+
+    SDL_SetHint(SDL_HINT_RENDER_SCALE_QUALITY, "linear");
+
+    app.renderer = SDL_CreateRenderer(app.window, -1, SDL_RENDERER_ACCELERATED);
+
+    if (app.renderer == NULL) {
+        printf("Renderer failed: %s\n", SDL_GetError());
+        return -1;
+    }
+
+    //SDL_SetRelativeMouseMode(SDL_TRUE);
+
+    SDL_Rect rect;
+
+    rect.x = SCREEN_WIDTH / SCREEN_HEIGHT;
+    rect.y = SCREEN_WIDTH / SCREEN_HEIGHT;
+    rect.w = SCREEN_WIDTH / 2;
+    rect.h = SCREEN_HEIGHT / 2;
+
+    SDL_Rect rect2;
+
+    rect2.x = 250;// / SCREEN_HEIGHT;
+    rect2.y = 250;// / SCREEN_HEIGHT;
+    rect2.w = SCREEN_WIDTH / 4;
+    rect2.h = SCREEN_HEIGHT / 4;
+
+    // Uint64 start = 0;
+    // Uint64 end = 0;
+    // float frameCount = 0;
+    // int count = 0;
+
+    while(!Exit) {
+        //start = SDL_GetPerformanceCounter();
+
+        SDL_Delay(16);
+
+        HandleInput();
+
+        SDL_SetRenderDrawColor(app.renderer, 0, 0, 255, 0);
+
+        SDL_RenderClear(app.renderer);
+
+        // if (count >= 100) {
+        //     snprintf(buffer, sizeof(buffer), "FPS: %.2f", count / frameCount);
+        //     count = 0;
+        //     frameCount = 0;
+        // }
+        SDL_SetRenderDrawColor(app.renderer, 0, 0, 0, 0);
+
+        SDL_RenderFillRect(app.renderer, &(SDL_Rect){rect.x + XRel, rect.y + YRel, rect.w, rect.h});
+
+        SDL_SetRenderDrawColor(app.renderer, 128, 0, 0, 0);
+
+        SDL_RenderFillRect(app.renderer, &(SDL_Rect){rect2.x + XRel, rect2.y + YRel, rect2.w, rect2.h});
+
+        SDL_RenderPresent(app.renderer);
+
+        // end = SDL_GetPerformanceCounter();
+
+        // frameCount += (end - start) / (float)SDL_GetPerformanceFrequency();
+
+        // count++;
+    }
+}
+
+void HandleInput(void) {
+    SDL_Event event;
+    while(SDL_PollEvent(&event)) {
+        switch (event.type) {
+            case SDL_QUIT:
+                Exit = 1;
+                break;
+            case SDL_MOUSEBUTTONDOWN:
+                MouseDown = 1;
+                break;
+            case SDL_MOUSEBUTTONUP:
+                MouseDown = 0;
+                break;
+            case SDL_MOUSEMOTION:
+                //if (MainMenu->HitCheck(event.motion.x, event.motion.y, &MainMenu->Area)) {
+                if (MouseDown){
+                    XRel += event.motion.xrel;
+                    YRel += event.motion.yrel;
+                }
+            case SDL_TEXTINPUT:
+            case SDL_KEYDOWN:
+            default:
+                break;
+        }
+    }
+}