make cart move

game.c

@@ -1,27 +1,47 @@
 #include <stdio.h>
+#include <math.h>
 #include <SDL2/SDL.h>
 #include <SDL2/SDL_image.h>
 #include <SDL2/SDL_timer.h>
+#define PI 3.14159265
 
-#define WINDOW_WIDTH 500
-#define WINDOW_HEIGHT 300
+#define WINDOW_WIDTH 700
+#define WINDOW_HEIGHT 500
+#define FPS 60
 
-int main(void){
-  SDL_Window* window;
-  SDL_Renderer* renderer;
-  SDL_Surface* surface;
-  SDL_Texture* texture;
+#define SPEED 400 // pixels per second
+#define STIRE_SPEED PI*2
 
+SDL_Window* window;
+SDL_Renderer* renderer;
+
+SDL_Texture* Car_texture;
+SDL_Rect Car_pos;
+
+SDL_Surface* surface;
+SDL_Texture* texture;
+
+void quit(void){
+  SDL_DestroyTexture(Car_texture);
+  SDL_DestroyTexture(texture);
+  SDL_DestroyRenderer(renderer);
+  SDL_DestroyWindow(window);
+  SDL_Quit();
+}
+
+// initialize SDL, create window and renderer
+int init(void){
   // initialize SDL
   if (SDL_Init(SDL_INIT_VIDEO|SDL_INIT_TIMER) != 0){
       printf("error initializing SDL: %s\n", SDL_GetError());
       return 1;
   }
+
   // create window
   window = SDL_CreateWindow("Cart Race",
                             SDL_WINDOWPOS_CENTERED,
                             SDL_WINDOWPOS_CENTERED,
-                            640, 480, 0);
+                            WINDOW_WIDTH, WINDOW_HEIGHT, 0);
   if(!window){
     printf("error create window: %s\n", SDL_GetError());
     SDL_Quit();
@@ -32,7 +52,7 @@ int main(void){
   renderer = SDL_CreateRenderer(
     window, -1,
     SDL_RENDERER_ACCELERATED|SDL_RENDERER_PRESENTVSYNC
-  ); 
+  );
 
   if(!renderer){
     printf("error create renderer: %s\n", SDL_GetError());
@@ -40,9 +60,39 @@ int main(void){
     SDL_Quit();
     return 3;
   }
+  return 0;
+}
+
+int createCar(){
+  // create surface
+  SDL_Surface* Car_surface = IMG_Load("img/car.png");
+  if(!Car_surface){
+    printf("error create surface: %s\n", SDL_GetError());
+    SDL_DestroyRenderer(renderer);
+    SDL_DestroyWindow(window);
+    SDL_Quit();
+    return 3;
+  }
+
+  // create texture
+  Car_texture = SDL_CreateTextureFromSurface(renderer, Car_surface);
+  SDL_FreeSurface(Car_surface);
+  if(!Car_texture){
+    printf("error create texture: %s\n", SDL_GetError());
+    SDL_DestroyRenderer(renderer);
+    SDL_DestroyWindow(window);
+    SDL_Quit();
+    return 3;
+  }
+  SDL_QueryTexture(Car_texture, NULL, NULL, &Car_pos.w, &Car_pos.h);
+  return 0;
+}
+
+int mainv1(void){
+  if(init() != 0) return 1;
 
   // create surface
-  surface = IMG_Load("img/hello.png");
+  surface = IMG_Load("img/car.png");
   if(!surface){
     printf("error create surface: %s\n", SDL_GetError());
     SDL_DestroyRenderer(renderer);
@@ -62,19 +112,212 @@ int main(void){
     return 3;
   }
 
-  // clear the window
-  SDL_RenderClear(renderer);
+  // car
+  SDL_Rect car;
+  SDL_QueryTexture(texture, NULL, NULL, &car.w, &car.h);
 
-  // drow image
-  SDL_RenderCopy(renderer, texture, NULL, NULL);
-  SDL_RenderPresent(renderer);
+  car.x = (WINDOW_WIDTH - car.w) / 2;
+  car.y = (WINDOW_HEIGHT- car.h) / 2;
 
-  // wait
-  SDL_Delay(5000);
+  Uint8 close_requested = 0;
+  int car_moving = 0;
+  int direction = 0;
+
+  double heading = PI;
+  double speed = SPEED / FPS;
+
+  while(!close_requested){
+    // process events
+    SDL_Event event;
+    while (SDL_PollEvent(&event)){
+      switch (event.type) {
+        case SDL_QUIT:
+          close_requested = 1;
+          break;
+        case SDL_KEYDOWN:
+          switch (event.key.keysym.scancode) {
+            case SDL_SCANCODE_UP:
+            case SDL_SCANCODE_W:
+              car_moving = 1;
+              break;
+            case SDL_SCANCODE_DOWN:
+            case SDL_SCANCODE_S:
+              car_moving = -1;
+              break;
+            case SDL_SCANCODE_LEFT:
+            case SDL_SCANCODE_A:
+              direction = 1;
+              break;
+            case SDL_SCANCODE_RIGHT:
+            case SDL_SCANCODE_D:
+              direction = -1;
+            default:
+              break;
+          }
+          break;
+        case SDL_KEYUP:
+          switch (event.key.keysym.scancode) {
+            case SDL_SCANCODE_UP:
+            case SDL_SCANCODE_W:
+            case SDL_SCANCODE_DOWN:
+            case SDL_SCANCODE_S:
+              car_moving = 0;
+              break;
+            case SDL_SCANCODE_LEFT:
+            case SDL_SCANCODE_A:
+            case SDL_SCANCODE_RIGHT:
+            case SDL_SCANCODE_D:
+              direction = 0;
+            default:
+              break;
+          }
+        default:
+          break;
+      }
+    }
+
+    // clear the window
+    SDL_RenderClear(renderer);
+
+    // update position
+    if(car_moving == 1){
+      car.x += (int) (sin(heading)*speed);
+      car.y += (int) (cos(heading)*speed);
+    }else if(car_moving == -1){
+      car.x -= (int) (sin(heading)*speed);
+      car.y -= (int) (cos(heading)*speed);
+    }
+
+    // drow image
+    SDL_RenderCopy(renderer, texture, NULL, &car);
+    SDL_RenderPresent(renderer);
+
+    // wait
+    SDL_Delay(1000 / FPS);
+  }
 
   // clean up resources before exiting
   SDL_DestroyTexture(texture);
   SDL_DestroyRenderer(renderer);
   SDL_DestroyWindow(window);
   SDL_Quit();
+  return 0;
+}
+
+int main(void){
+  if(init() != 0) return 1;
+  if(createCar() != 0) return 2;
+
+  Car_pos.x = (WINDOW_WIDTH - Car_pos.w) / 2;
+  Car_pos.y = (WINDOW_HEIGHT- Car_pos.h) / 2;
+
+  Uint8 close_requested = 0;
+  int car_moving = 0;
+  int direction = 0;
+
+  double heading = PI;
+  double speed = SPEED / FPS;
+  double sspeed = STIRE_SPEED / FPS;
+
+  double car_pos[2] = {Car_pos.x, Car_pos.y};
+
+  while(!close_requested){
+    // process events
+    SDL_Event event;
+    if(SDL_PollEvent(&event)){
+      switch (event.type) {
+        case SDL_QUIT:
+          close_requested = 1;
+          break;
+        case SDL_KEYDOWN:
+          switch (event.key.keysym.scancode) {
+            case SDL_SCANCODE_UP:
+            case SDL_SCANCODE_W:
+              car_moving = 1;
+              break;
+            case SDL_SCANCODE_DOWN:
+            case SDL_SCANCODE_S:
+              car_moving = -1;
+              break;
+            case SDL_SCANCODE_LEFT:
+            case SDL_SCANCODE_A:
+              direction = 1;
+              break;
+            case SDL_SCANCODE_RIGHT:
+            case SDL_SCANCODE_D:
+              direction = -1;
+            default:
+              break;
+          }
+          break;
+        case SDL_KEYUP:
+          switch (event.key.keysym.scancode) {
+            case SDL_SCANCODE_UP:
+            case SDL_SCANCODE_W:
+            case SDL_SCANCODE_DOWN:
+            case SDL_SCANCODE_S:
+              car_moving = 0;
+              break;
+            case SDL_SCANCODE_LEFT:
+            case SDL_SCANCODE_A:
+            case SDL_SCANCODE_RIGHT:
+            case SDL_SCANCODE_D:
+              direction = 0;
+            default:
+              break;
+          }
+        default:
+          break;
+      }
+    }
+
+    // clear the window
+    SDL_RenderClear(renderer);
+
+    // update position
+    if(direction == 1){
+      heading += sspeed;
+    }else if(direction == -1){
+      heading -= sspeed;
+    }
+    if(car_moving == 1){
+      car_pos[0] += (sin(heading)*speed);
+      car_pos[1] += (cos(heading)*speed);
+    }else if(car_moving == -1){
+      car_pos[0] -= (sin(heading)*speed);
+      car_pos[1] -= (cos(heading)*speed);
+    }
+
+    if(car_pos[0] < 0){
+      car_pos[0] = 0;
+    }else if(car_pos[0]+Car_pos.w > WINDOW_WIDTH){
+      car_pos[0] = WINDOW_WIDTH-Car_pos.w;
+    }
+    if(car_pos[1]< 0){
+      car_pos[1]= 0;
+    }else if(car_pos[1]+Car_pos.w > WINDOW_HEIGHT){
+      car_pos[1]= WINDOW_HEIGHT-Car_pos.w;
+    }
+
+    Car_pos.x = (int) car_pos[0];
+    Car_pos.y = (int) car_pos[1];
+
+    printf("heading: %f\t%d\n", (heading), direction);
+    printf("car posf: %f, %f\n", car_pos[0], car_pos[1]);
+    printf("car pos: %u, %u\t%d\n", Car_pos.x, Car_pos.y, car_moving);
+
+    // drow image
+    SDL_RenderCopyEx(renderer, Car_texture, NULL, &Car_pos, 180-(heading*(180/PI)), NULL, SDL_FLIP_NONE);
+    SDL_RenderPresent(renderer);
+
+    // wait
+    SDL_Delay(1000 / FPS);
+  }
+
+  // clean up resources before exiting
+  SDL_DestroyTexture(texture);
+  SDL_DestroyRenderer(renderer);
+  SDL_DestroyWindow(window);
+  SDL_Quit();
+  return 0;
 }