added serial spaceball support in the dos version. can be used for

[dosdemo] / src / vmath.h

diff --git a/src/vmath.h b/src/vmath.h
new file mode 100644 (file)
index 0000000..d8c6be2
--- /dev/null
+++ b/src/vmath.h
@@ -0,0 +1,99 @@
+#ifndef VMATH_H_
+#define VMATH_H_
+
+#ifdef __GNUC__
+#define INLINE __inline
+
+#elif defined(__WATCOMC__)
+#define INLINE __inline
+
+#else
+#define INLINE
+#endif
+
+typedef struct { float x, y, z; } vec3_t;
+typedef struct { float x, y, z, w; } vec4_t;
+
+typedef vec4_t quat_t;
+
+/* vector functions */
+static INLINE vec3_t v3_cons(float x, float y, float z)
+{
+       vec3_t res;
+       res.x = x;
+       res.y = y;
+       res.z = z;
+       return res;
+}
+
+static INLINE float v3_dot(vec3_t v1, vec3_t v2)
+{
+       return v1.x * v2.x + v1.y * v2.y + v1.z * v2.z;
+}
+
+/* quaternion functions */
+static INLINE quat_t quat_cons(float s, float x, float y, float z)
+{
+       quat_t q;
+       q.x = x;
+       q.y = y;
+       q.z = z;
+       q.w = s;
+       return q;
+}
+
+static INLINE vec3_t quat_vec(quat_t q)
+{
+       vec3_t v;
+       v.x = q.x;
+       v.y = q.y;
+       v.z = q.z;
+       return v;
+}
+
+static INLINE quat_t quat_mul(quat_t q1, quat_t q2)
+{
+       quat_t res;
+       vec3_t v1 = quat_vec(q1);
+       vec3_t v2 = quat_vec(q2);
+
+       res.w = q1.w * q2.w - v3_dot(v1, v2);
+       res.x = v2.x * q1.w + v1.x * q2.w + (v1.y * v2.z - v1.z * v2.y);
+       res.y = v2.y * q1.w + v1.y * q2.w + (v1.z * v2.x - v1.x * v2.z);
+       res.z = v2.z * q1.w + v1.z * q2.w + (v1.x * v2.y - v1.y * v2.x);
+       return res;
+}
+
+static INLINE void quat_to_mat(float *res, quat_t q)
+{
+       res[0] = 1.0f - 2.0f * q.y*q.y - 2.0f * q.z*q.z;
+       res[1] = 2.0f * q.x * q.y - 2.0f * q.w * q.z;
+       res[2] = 2.0f * q.z * q.x + 2.0f * q.w * q.y;
+       res[3] = 0.0f;
+       res[4] = 2.0f * q.x * q.y + 2.0f * q.w * q.z;
+       res[5] = 1.0f - 2.0f * q.x*q.x - 2.0f * q.z*q.z;
+       res[6] = 2.0f * q.y * q.z - 2.0f * q.w * q.x;
+       res[7] = 0.0f;
+       res[8] = 2.0f * q.z * q.x - 2.0f * q.w * q.y;
+       res[9] = 2.0f * q.y * q.z + 2.0f * q.w * q.x;
+       res[10] = 1.0f - 2.0f * q.x*q.x - 2.0f * q.y*q.y;
+       res[11] = 0.0f;
+       res[12] = res[13] = res[14] = 0.0f;
+       res[15] = 1.0f;
+}
+
+static INLINE quat_t quat_rotate(quat_t q, float angle, float x, float y, float z)
+{
+       quat_t rq;
+       float half_angle = angle * 0.5;
+       float sin_half = sin(half_angle);
+
+       rq.w = cos(half_angle);
+       rq.x = x * sin_half;
+       rq.y = y * sin_half;
+       rq.z = z * sin_half;
+
+       return quat_mul(q, rq);
+}
+
+#endif /* VMATH_H_ */