polarity

CMakeLists.txt

@@ -16,6 +16,7 @@ set(SOURCES
 	src/input.c
 	src/level.c
 	src/player.c
+	src/polarity.c
 )
 
 set(ASSETS

inc/input.h

@@ -1,6 +1,6 @@
 #pragma once
 
-enum Key { K_LEFT, K_RIGHT, K_UP, K_DOWN, K_JUMP, K_EXIT, K_COUNT };
+enum Key { K_LEFT, K_RIGHT, K_UP, K_DOWN, K_JUMP, K_POLARITY, K_EXIT, K_COUNT };
 enum KeyState { KS_UP, KS_DOWN, KS_PRESS };
 
 struct Input {

inc/polarity.h

@@ -0,0 +1,4 @@
+#pragma once
+
+int polarity(void);
+void polarity_invert(void);

inc/tile.h

@@ -3,6 +3,8 @@
 enum Tile {
 	TILE_AIR,
 	TILE_SOLID,
+	TILE_RED,
+	TILE_BLUE,
 	TILE_SPAWN,
 	TILE_EXIT,
 	TILE_BURN,

src/input.c

@@ -2,8 +2,8 @@
 #include <gint/keyboard.h>
 
 static struct Input input;
-static const int default_map[K_COUNT] = {KEY_LEFT, KEY_RIGHT, KEY_UP,
-                                         KEY_DOWN, KEY_SHIFT, KEY_EXIT};
+static const int default_map[K_COUNT] = {
+    KEY_LEFT, KEY_RIGHT, KEY_UP, KEY_DOWN, KEY_SHIFT, KEY_ALPHA, KEY_EXIT};
 
 void
 input_init(void)

src/level.c

@@ -1,6 +1,7 @@
 #include "level.h"
 #include "conf.h"
 #include "player.h"
+#include "polarity.h"
 #include "tile.h"
 #include "vec.h"
 #include "visual_data.h"
@@ -79,6 +80,16 @@ level_regen_visual_data(void)
 			vd->img_x = tile % tileset_width * TILE_SIZE;
 			vd->img_y = (int)(tile / tileset_width) * TILE_SIZE;
 			vd->visible = tile != 0;
+			switch (tile) {
+			case TILE_RED:
+				vd->img_y += polarity() ? TILE_SIZE : 0;
+				break;
+			case TILE_BLUE:
+				vd->img_y += polarity() ? 0 : TILE_SIZE;
+				break;
+			default:
+				break;
+			}
 		}
 	}
 }

src/player.c

@@ -3,6 +3,7 @@
 #include "draw.h"
 #include "input.h"
 #include "level.h"
+#include "polarity.h"
 #include "tile.h"
 #include "util.h"
 
@@ -35,8 +36,12 @@ player_update(struct Player *p)
 	// const int k_down = input_down(K_DOWN);
 	const int k_jump = input_down(K_JUMP);
 	const int kp_jump = input_pressed(K_JUMP);
+	const int kp_polarity = input_pressed(K_POLARITY);
 	const int dir_x = k_right - k_left;
 
+	/* polarity swap */
+	if (kp_polarity) polarity_invert();
+
 	/* horizontal friction & acceleration */
 	p->spd.x *= on_ground ? (1 - GROUND_FRICTION) : (1 - AIR_FRICTION);
 	p->spd.x +=
@@ -116,6 +121,11 @@ player_move(struct Player *p, struct Vec spd)
 	const int sign_y = sign(spd.y);
 	if (!sign_x && !sign_y) sign_x = 1.0f;
 
+	if (collide_solid(p->pos.x, p->pos.y)) {
+		reset_speed(p, 1, 1);
+		return;
+	}
+
 	p->pos.x += spd.x;
 	if (collide_solid(p->pos.x, p->pos.y)) reset_speed(p, 1, 0);
 	while (collide_solid(p->pos.x, p->pos.y))
@@ -170,5 +180,7 @@ collide(int x, int y, int tile)
 static int
 collide_solid(int x, int y)
 {
-	return collide(x, y, TILE_SOLID);
+	return collide(x, y, TILE_SOLID) ||
+	       (!polarity() && collide(x, y, TILE_RED)) ||
+	       (polarity() && collide(x, y, TILE_BLUE));
 }

src/polarity.c

@@ -0,0 +1,17 @@
+#include "polarity.h"
+#include "level.h"
+
+static int pol = 0;
+
+int
+polarity(void)
+{
+	return pol;
+}
+
+void
+polarity_invert(void)
+{
+	pol = !pol;
+	level_regen_visual_data();
+}