From 8bb2aa21e11eecbff71bb842efd64176e77a45cb Mon Sep 17 00:00:00 2001
From: Gregory Eremin <g@erem.in>
Date: Mon, 5 Oct 2015 12:38:42 +0300
Subject: [PATCH] First attempt on handling bounce direction

---
 src/brick.cpp | 29 ++++++++++++++++++++++-------
 src/brick.hpp | 10 +++++++++-
 src/scene.cpp | 29 ++++++++++++++++++++++++-----
 3 files changed, 55 insertions(+), 13 deletions(-)

diff --git a/src/brick.cpp b/src/brick.cpp
index 8814dcb..29030ac 100644
--- a/src/brick.cpp
+++ b/src/brick.cpp
@@ -12,14 +12,29 @@ Brick::Brick(SDL_Renderer *r, int x, int y, Color c) {
 
 Brick::~Brick() {}
 
-bool Brick::collides_with(int x1, int y1, int x2, int y2) {
-    return (
+BounceDirection Brick::collide(int x1, int y1, int x2, int y2) {
+    if (!(
         visible &&
-        brick.x < x2 &&
-        brick.x + BRICK_WIDTH > x1 &&
-        brick.y < y2 &&
-        brick.y + BRICK_HEIGHT > y1
-    );
+        brick.x <= x2 &&
+        brick.x + BRICK_WIDTH >= x1 &&
+        brick.y <= y2 &&
+        brick.y + BRICK_HEIGHT >= y1
+    )) {
+        return None;
+    }
+
+    if (y1 <= brick.y - BRICK_HEIGHT/2) {
+        return Bottom;
+    } else if (y1 >= brick.y + (BRICK_HEIGHT/2)) {
+        return Top;
+    } else if (x1 < brick.x) {
+        return Left;
+    } else if (x1 > brick.x) {
+        return Right;
+    } else {
+        DEBUG("WTF!");
+        return None;
+    }
 }
 
 void Brick::destroy() {
diff --git a/src/brick.hpp b/src/brick.hpp
index 2cacff8..ab63b99 100644
--- a/src/brick.hpp
+++ b/src/brick.hpp
@@ -11,12 +11,20 @@ typedef enum Color {
     PURPLE
 } Color;
 
+typedef enum BounceDirection {
+    None,
+    Top,
+    Bottom,
+    Left,
+    Right
+} BounceDirection;
+
 class Brick {
 public:
     Brick(SDL_Renderer *r, int x, int y, Color c);
     ~Brick();
 
-    bool collides_with(int x1, int y1, int x2, int y2);
+    BounceDirection collide(int x1, int y1, int x2, int y2);
     void destroy();
     void render();
 private:
diff --git a/src/scene.cpp b/src/scene.cpp
index e9f8cc3..e5f54f6 100644
--- a/src/scene.cpp
+++ b/src/scene.cpp
@@ -66,9 +66,16 @@ void Scene::move_pad_relative(int delta) {
 }
 
 void Scene::launch_ball() {
+    ball.x = SCREEN_WIDTH/2 - BALL_RADIUS;
+    ball.y = SCREEN_HEIGHT/2 - BALL_RADIUS;
     ball_moving = true;
+
     ball_velx = 3;
-    ball_vely = -2;
+    ball_vely = 5;
+
+    if (rand() > RAND_MAX/2) {
+        ball_velx = -ball_velx;
+    }
 }
 
 void Scene::move_ball() {
@@ -95,22 +102,34 @@ void Scene::move_ball() {
     }
     // Bottom
     if (ball.y >= SCREEN_HEIGHT) {
-        // Game over
+        launch_ball();
+        DEBUG("Loser!");
     }
     // Pad
     if (ball.x >= pad.x && ball.x <= pad.x + PAD_WIDTH && ball.y + 2*BALL_RADIUS >= pad.y) {
         ball_vely = -ball_vely;
     }
     // Bricks
-    for (int i = NUM_BRICKS; i > 0; --i) {
+    for (int i = NUM_BRICKS; i >= 0; --i) {
         int x1 = ball.x;
         int y1 = ball.y;
         int x2 = ball.x + 2*BALL_RADIUS;
         int y2 = ball.y + 2*BALL_RADIUS;
 
-        if (bricks[i].collides_with(x1, y1, x2, y2)) {
+        BounceDirection dir = bricks[i].collide(x1, y1, x2, y2);
+        switch (dir) {
+        case None:
+            continue;
+        case Top:
+        case Bottom:
             ball_vely = -ball_vely;
-            bricks[i].destroy();
+            break;
+        case Left:
+        case Right:
+            ball_velx = -ball_velx;
+            break;
         }
+
+        bricks[i].destroy();
     }
 }