Merge branch 'brainstorming-systems' into ral

1 files changed, 19 insertions, 5 deletions

diff --git a/src/maths/maths.h b/src/maths/maths.h
index c9bcaad..638d9f6 100644
--- a/src/maths/maths.h
+++ b/src/maths/maths.h
@@ -64,13 +64,25 @@ static inline vec4 vec4_create(f32 x, f32 y, f32 z, f32 w) { return (vec4){ x, y
 static inline f32 quat_dot(quat a, quat b) { return a.x * b.x + a.y * b.y + a.z * b.z + a.w * b.w; }
 
 static inline quat quat_normalise(quat a) {
-  f32 length = sqrtf(quat_dot(a, a)  // same as len squared
-  );
+  f32 length = sqrtf(quat_dot(a, a));  // same as len squared
+
   return (quat){ a.x / length, a.y / length, a.z / length, a.w / length };
 }
 
 static inline quat quat_ident() { return (quat){ .x = 0.0, .y = 0.0, .z = 0.0, .w = 1.0 }; }
 
+static quat quat_from_axis_angle(vec3 axis, f32 angle, bool normalize) {
+  const f32 half_angle = 0.5f * angle;
+  f32 s = sinf(half_angle);
+  f32 c = cosf(half_angle);
+
+  quat q = (quat){ s * axis.x, s * axis.y, s * axis.z, c };
+  if (normalize) {
+    return quat_normalise(q);
+  }
+  return q;
+}
+
 // --- Matrix Implementations
 
 static inline mat4 mat4_ident() {
@@ -246,12 +258,14 @@ static inline mat4 mat4_look_at(vec3 position, vec3 target, vec3 up) {
                 .is_dirty = false })
 
 static transform transform_create(vec3 pos, quat rot, f32 scale) {
-  return (transform){ .position = pos, .rotation = rot, .scale = scale, .is_dirty = false };
+  return (transform){ .position = pos, .rotation = rot, .scale = scale, .is_dirty = true };
 }
 
 static inline mat4 transform_to_mat(transform *tf) {
-  // TODO: rotation
-  return mat4_mult(mat4_translation(tf->position), mat4_scale(tf->scale));
+  mat4 trans = mat4_translation(tf->position);
+  mat4 rot = mat4_rotation(tf->rotation);
+  mat4 scale = mat4_scale(tf->scale);
+  return mat4_mult(trans, mat4_mult(rot, scale));
 }
 
 // --- Sizing asserts