Introduce cannon and projectile structs

1 files changed, 66 insertions, 48 deletions

diff --git a/main.c b/main.c
index 8a4fd34..9bcd467 100644
--- a/main.c
+++ b/main.c
@@ -1,12 +1,31 @@
 #include <assert.h>
 #include <stdio.h>
 #include <stdlib.h>
+#include <math.h>
 #include <SDL2/SDL.h>
 
+#define GRAVITY -9.8
+#define PI 3.141592
 #define WINDOW_W 1280
 #define WINDOW_H 720
 #define WALK_VEL 20
 
+typedef struct {
+	float x;
+	float y;
+	float vy;
+	float angle;
+	float power;
+} Cannon;
+
+typedef struct {
+	float x;
+	float y;
+	float vy;
+	float vx;
+	int alive;
+} Projectile;
+
 static inline double GetCurrentTimestamp() {
 	return (double) SDL_GetTicks64() / 1000.0;
 }
@@ -70,17 +89,12 @@ void GameMain(SDL_Renderer *context) {
 		mask[i] = 1.0;
 	}
 
-	float player_x = 100;
-	float player_y = 500;
-	float player_vy = 0;
-	float player_ay = -9.8;
+	Cannon player = {0};
+	player.x = 100;
+	player.y = 500;
+	player.power = 100;
 
-	float projectile_x = 100;
-	float projectile_y = 500;
-	float projectile_vy = 100;
-	float projectile_vx = 5;
-	float projectile_ay = -9.8;
-	int projectile_alive = 0;
+	Projectile projectile = {0};
 
 	float old_t = 0.0;
 
@@ -94,59 +108,61 @@ void GameMain(SDL_Renderer *context) {
 		while (SDL_PollEvent(&event)) {
 			if (event.type == SDL_QUIT) {
 				exit = 1;
-			} else if (event.type == SDL_KEYDOWN && event.key.state == SDL_PRESSED && event.key.keysym.sym == SDLK_SPACE && !projectile_alive) {
-				projectile_alive = 1;
-				projectile_x = player_x;
-				projectile_y = player_y + 10;
+			} else if (event.type == SDL_KEYDOWN && event.key.state == SDL_PRESSED && event.key.keysym.sym == SDLK_SPACE && !projectile.alive) {
+				projectile.alive = 1;
+				projectile.x = player.x;
+				projectile.y = player.y;
+				projectile.vy = sin(player.angle) * player.power;
+				projectile.vx = cos(player.angle) * player.power;
 			}
 		}
 		int mouse_x, mouse_y;
 		Uint32 mouse_state = SDL_GetMouseState(&mouse_x, &mouse_y);
 		float size = 20;
 		if (mouse_state & SDL_BUTTON_LMASK) {
-			PaintMask(mask, WINDOW_W, WINDOW_H, mouse_x, mouse_y, 1.0, size);
+			PaintMask(mask, WINDOW_W, WINDOW_H, mouse_x, WINDOW_H - mouse_y, 1.0, size);
 		} else if (mouse_state & SDL_BUTTON_RMASK) {
-			PaintMask(mask, WINDOW_W, WINDOW_H, mouse_x, mouse_y, 0.0, size);
+			PaintMask(mask, WINDOW_W, WINDOW_H, mouse_x, WINDOW_H - mouse_y, 0.0, size);
 		}
 
 		const Uint8 *keys = SDL_GetKeyboardState(0);
-		if (keys[SDL_SCANCODE_D]) {
-			player_x += WALK_VEL * dt;
+		if (keys[SDL_SCANCODE_D] && player.x < WINDOW_W) {
+			player.x += WALK_VEL * dt;
 		}
-		if (keys[SDL_SCANCODE_A]) {
-			player_x -= WALK_VEL * dt;
+		if (keys[SDL_SCANCODE_A] && player.x >= 0) {
+			player.x -= WALK_VEL * dt;
 		}
-
-		if (player_x < 0) {
-			player_x += WALK_VEL * dt;
-		} else if (player_x >= WINDOW_W) {
-			player_x -= WALK_VEL * dt;
+		if (keys[SDL_SCANCODE_W] && player.angle < PI / 2) {
+			player.angle += PI / 180 * dt;
 		}
-		if (player_y >= WINDOW_H) {
-			player_y  = WINDOW_H - 1;
-			player_vy = 0;
+		if (keys[SDL_SCANCODE_S] && player.angle > 0) {
+			player.angle -= PI / 180 * dt;
 		}
-		if (mask[(int)player_x + (int)player_y * WINDOW_W] == 0.0 &&
-				player_y >= 0) {
-			player_y += player_vy * dt;
-			player_vy += player_ay * dt;
-			while (mask[(int)player_x + (int)player_y * WINDOW_W] != 0.0) {
-				player_y += 1;
-				player_vy = 0;
+
+		if (player.y >= WINDOW_H) {
+			player.y  = WINDOW_H - 1;
+			player.vy = 0;
+		}
+		if (mask[(int)player.x + (int)player.y * WINDOW_W] == 0.0 &&
+				player.y >= 0) {
+			player.y += player.vy * dt;
+			player.vy += GRAVITY * dt;
+			while (mask[(int)player.x + (int)player.y * WINDOW_W] != 0.0) {
+				player.y += 1;
+				player.vy = 0;
 			}
 		}
 
-		if (projectile_alive) {
-			if (projectile_y >= 0 && projectile_y < WINDOW_H &&
-					projectile_x >= 0 && projectile_x < WINDOW_W &&
-					mask[(int)projectile_x + (int)projectile_y * WINDOW_W] == 0.0) {
-				projectile_x += projectile_vx * dt;
-				projectile_y += projectile_vy * dt;
-				projectile_vy += projectile_ay * dt;
+		if (projectile.alive) {
+			if (projectile.y >= 0 && projectile.y < WINDOW_H &&
+					projectile.x >= 0 && projectile.x < WINDOW_W &&
+					mask[(int)projectile.x + (int)projectile.y * WINDOW_W] == 0.0) {
+				projectile.x += projectile.vx * dt;
+				projectile.y += projectile.vy * dt;
+				projectile.vy += GRAVITY * dt;
 			} else {
-				projectile_alive = 0;
-				projectile_vy = 100;
-				PaintMask(mask, WINDOW_W, WINDOW_H, projectile_x, projectile_y, 0.0, 40);
+				projectile.alive = 0;
+				PaintMask(mask, WINDOW_W, WINDOW_H, projectile.x, projectile.y, 0.0, 40);
 			}
 		}
 
@@ -175,12 +191,14 @@ void GameMain(SDL_Renderer *context) {
 		SDL_RenderCopy(context, terrain, 0, 0);
 
 		SDL_SetRenderDrawColor(context, 255, 0, 0, 255);
-		SDL_Rect player_rect = {player_x - 5, WINDOW_H - player_y - 10, 10, 10 };
+		SDL_Rect player_rect = {player.x - 5, WINDOW_H - player.y - 10, 10, 10 };
 		SDL_RenderFillRect(context, &player_rect);
 
-		if (projectile_alive) {
+		SDL_RenderDrawLine(context, player.x, WINDOW_H - player.y, player.x + cos(player.angle) * 100, WINDOW_H - player.y - sin(player.angle) * 100);
+
+		if (projectile.alive) {
 			SDL_SetRenderDrawColor(context, 0, 255, 0, 255);
-			SDL_Rect projectile_rect = {projectile_x - 5, WINDOW_H - projectile_y - 10, 10, 10 };
+			SDL_Rect projectile_rect = {projectile.x - 5, WINDOW_H - projectile.y - 10, 10, 10 };
 			SDL_RenderFillRect(context, &projectile_rect);
 		}