From 8f0b65e07c44bbf23e589ad991e9c0e2511c079f Mon Sep 17 00:00:00 2001
From: Miriam Ruiz <miriam@debian.org>
Date: Fri, 20 Apr 2012 17:03:22 +0200
Subject: [PATCH] Fixed Collision

---
 engine/game.py | 82 ++++++++++++++++++++++++++++++++++++++++++++--------------
 1 file changed, 62 insertions(+), 20 deletions(-)

diff --git a/engine/game.py b/engine/game.py
index b6c475e..4526ac1 100644
--- a/engine/game.py
+++ b/engine/game.py
@@ -171,7 +171,8 @@ def start(screen, map_filename, hero):
 		step_y = speed_factor * speed * dt * direction_y / dir_len
 		if metadata_layer is not None:
 			try:
-				step_x, step_y = check_collision(hero_pos_x, hero_pos_y, step_x, step_y, hero.width, hero.height, metadata_layer, tile_properties)
+				step_x, step_y = check_movement(hero_pos_x, hero_pos_y, step_x, step_y, \
+					hero.width, hero.height, metadata_layer, tile_properties)
 			except:
 				pass
 		hero_pos_x += step_x
@@ -196,11 +197,46 @@ def start(screen, map_filename, hero):
 			else:
 				renderer.render_layer(screen, sprite_layer)
 
+		tile_width = metadata_layer.tilewidth
+		tile_height = metadata_layer.tileheight
+		tile_x_left = int((hero_pos_x - hero.width // 2) // tile_width)
+		tile_x_right = int((hero_pos_x + hero.width // 2) // tile_width + 1)
+		tile_y_up = int((hero_pos_y - hero.height) // tile_height)
+		tile_y_down = int((hero_pos_y) // tile_height + 1)
+		#show_rectangle(screen, renderer, hero_pos_x - 2, hero_pos_y - 2, 5, 5)
+		show_rectangle(screen, renderer, tile_x_left * tile_width - 2, tile_y_up * tile_height - 2, 5, 5)
+		show_rectangle(screen, renderer, tile_x_left * tile_width - 2, tile_y_down * tile_height - 2, 5, 5)
+		show_rectangle(screen, renderer, tile_x_right * tile_width - 2, tile_y_up * tile_height - 2, 5, 5)
+		show_rectangle(screen, renderer, tile_x_right * tile_width - 2, tile_y_down * tile_height - 2, 5, 5)
+
 		pygame.display.flip()
 
+def show_rectangle(screen, renderer, x, y, w, h):
+	pygame.draw.rect(screen, (255, 255, 255), (x - renderer._render_cam_rect.x, y - renderer._render_cam_rect.y, w, h))
+
 #  -----------------------------------------------------------------------------
 
-def check_collision(hero_pos_x, hero_pos_y, step_x, step_y, \
+def check_collision(hero_pos_x, hero_pos_y, hero_width, hero_height, metadata_layer, tile_properties):
+	tile_width = metadata_layer.tilewidth
+	tile_height = metadata_layer.tileheight
+
+	half_hero_width = hero_width // 2
+	half_hero_height = hero_height // 2
+
+	tile_x_left = int((hero_pos_x - half_hero_width) // tile_width)
+	tile_x_right = int((hero_pos_x + half_hero_width) // tile_width + 1)
+	tile_y_up = int((hero_pos_y - hero_height) // tile_height)
+	tile_y_down = int((hero_pos_y) // tile_height + 1)
+
+	for y in range(tile_y_up, tile_y_down):
+		for x in range(tile_x_left, tile_x_right):
+			gid = metadata_layer.content2D[x][y]
+			if gid in tile_properties:
+				return True
+
+	return False
+
+def check_movement(hero_pos_x, hero_pos_y, step_x, step_y, \
 					hero_width, hero_height, metadata_layer, tile_properties):
 	"""
 	Checks collision of the hero against the world. Its not the best way to
@@ -219,39 +255,45 @@ def check_collision(hero_pos_x, hero_pos_y, step_x, step_y, \
 	half_hero_width = hero_width // 2
 	half_hero_height = hero_height // 2
 
+	tile_x_left = int((hero_pos_x - half_hero_width) // tile_width)
+	tile_x_right = int((hero_pos_x + half_hero_width) // tile_width + 1)
+	tile_y_up = int((hero_pos_y - hero_height) // tile_height)
+	tile_y_down = int((hero_pos_y) // tile_height + 1)
+
 	if step_x < 0:
-		sx = int((hero_pos_x - half_hero_width) // tile_width)
-		ex = int((hero_pos_x - half_hero_width - step_x) // tile_width)
+		sx = tile_x_left
+		ex = int((hero_pos_x - half_hero_width + step_x) // tile_width)
 	elif step_x > 0:
-		sx = int((hero_pos_x + half_hero_width) // tile_width)
+		sx = tile_x_right
 		ex = int((hero_pos_x + half_hero_width + step_x) // tile_width)
 	else:
 		sx = int((hero_pos_x) // tile_width)
 		ex = sx
 
 	if step_y < 0:
-		sy = int((hero_pos_y - hero_height) // tile_height)
-		ey = int((hero_pos_y - hero_height - step_y) // tile_height)
+		sy = tile_y_up
+		ey = int((hero_pos_y - hero_height + step_y) // tile_height)
 	elif step_y > 0:
-		sy = int((hero_pos_y) // tile_height)
+		sy = tile_y_down
 		ey = int((hero_pos_y + step_y) // tile_height)
 	else:
-		sy = int((hero_pos_y) // tile_height)
+		sy = int((hero_pos_y - half_hero_height) // tile_height)
 		ey = sy
 
-	gid = metadata_layer.content2D[sx][sy]
-	if gid in tile_properties:
-		return 0,0
+	for y in range(tile_y_up, tile_y_down):
+		gid = metadata_layer.content2D[ex][y]
+		if gid in tile_properties:
+			step_x = 0
+			ex = sx
 
-	gid = metadata_layer.content2D[ex][sy]
-	if gid in tile_properties:
-		step_x = 0
-		ex = sx
+	xl = int((hero_pos_x - half_hero_width + step_x) // tile_width)
+	xr = int((hero_pos_x + half_hero_width + step_x) // tile_width + 1)
 
-	gid = metadata_layer.content2D[ex][ey]
-	if gid in tile_properties:
-		step_y = 0
-		ey = sy
+	for x in range(xl, xr):
+		gid = metadata_layer.content2D[x][ey]
+		if gid in tile_properties:
+			step_y = 0
+			ey = sy
 
 	# return the step the hero should do
 	return step_x, step_y
-- 
2.11.4.GIT