1 files changed, 46 insertions, 0 deletions
diff --git a/scene.cpp b/scene.cpp
new file mode 100644
index 0000000..47b76bf
--- /dev/null
+++ b/scene.cpp
@@ -0,0 +1,46 @@
+#include "scene.h"
+
+#include <SDL_opengl.h>
+
+#include <cmath>
+
+#define inrange(a, b, c) ((a) >= (b) && (a) <= (c))
+
+void Scene::lookat() {
+	/* calculate cartesian coordinates for the center vector where yaw is Φ and pitch is θ
+	 * x = cos Φ sin θ
+	 * y = cos θ
+	 * z = sin Φ sin θ
+	 */
+	Vector3 center(sinf(pitch) * cosf(yaw), cosf(pitch), sinf(pitch) * sinf(yaw));
+	center += pos;
+	center.y += 1;
+	//Vector3 up(cosf(yaw) * cosf(pitch), sinf(pitch), sinf(yaw) * cosf(pitch));
+	Vector3 up(-cosf(pitch) * cosf(yaw), sinf(pitch), -cosf(pitch) * sinf(yaw));
+	gluLookAt(pos.x, pos.y+1, pos.z,
+			center.x, center.y, center.z,
+			up.x, up.y, up.z);
+}
+
+void Scene::move(float forward, float right, int steps) {
+	Vector2 dir;
+	dir.x += forward*cosf(yaw);
+	dir.y += forward*sinf(yaw);
+
+	dir.x += right*cosf(yaw+M_PI_2);
+	dir.y += right*sinf(yaw+M_PI_2);
+
+	// ensure that the vector length is 1.0
+	dir /= dir.length();
+	dir *= 0.005;
+	dir *= steps;
+
+	float x = pos.x + dir.x;
+	//if(inrange(x, -2, 2))
+		pos.x = x;
+	float z = pos.z + dir.y;
+	//if(inrange(z, -2, 2))
+		pos.z = z;
+	//pos.x += dir.x;
+	//pos.z += dir.y;
+}