1 files changed, 30 insertions, 0 deletions
diff --git a/src/common.hpp b/src/common.hpp
index 181139f..6042e08 100644
--- a/src/common.hpp
+++ b/src/common.hpp
@@ -260,6 +260,7 @@ namespace game {
 		void start(void);
 		void stop(void);
 		void tick(ntime_t time);
+		void compute_ambience(render::state_t *render);
 		void pause(void);
 		void resume(void);
 
@@ -389,11 +390,14 @@ namespace render {
 		void render_line(v2f_t x0, v2f_t x1, sf::Color color);
 
 		void debug_path(v2f_t x, std::list<v2f_t> *path);
+
+		rectf_t window_in_world_space(void);
 	};
 }
 
 namespace audio {
 	void clean_sounds(void);
+	void update_ambience(bool playing);
 
 	class sound_t {
 		sf::SoundBuffer buffer;
@@ -402,6 +406,15 @@ namespace audio {
 		void load(const char *path);
 		void play(void);
 	};
+
+	class ambient_t {
+	public:
+		sf::Music sound;
+		bool playing = false;
+		float weight = 0.0f;
+
+		void load(const char *path);
+	};
 }
 
 extern render::state_t *debug_render;
@@ -429,6 +442,23 @@ T lerp(T a, T b, T x)
 	return a * (1 - x) + b * x;
 }
 
+// Linear map between intervals.
+template <typename T>
+T remap(T am, T ap, T bm, T bp, T x)
+{
+	return (x - am) * (bp - bm) / (ap - am) + bm;
+}
+
+template <typename T>
+T clamp(T x, T m, T p)
+{
+	if (x < m)
+		return m;
+	if (x > p)
+		return p;
+	return x;
+}
+
 // Bilinear interpolation.
 template <typename T>
 T bilerp(T a, T b, T c, T d, T x, T y)