audio rework pt 1

[vg.git] / src / vg / vg_m.h

diff --git a/src/vg/vg_m.h b/src/vg/vg_m.h
index 8ecadbdbdf1a19eddaa336f5c6f82efc2a4fa1d9..5bbb46733bbb0482d532d36d885d35ad4effecad 100644 (file)
--- a/src/vg/vg_m.h
+++ b/src/vg/vg_m.h
@@ -1,4 +1,11 @@
-/* Copyright (C) 2021 Harry Godden (hgn) - All Rights Reserved */
+/* Copyright (C) 2021-2022 Harry Godden (hgn) - All Rights Reserved */
+
+#ifndef VG_M_H
+#define VG_M_H
+
+#include "vg_platform.h"
+#include <math.h>
+#include <stdlib.h>
 
 #define VG_PIf  3.14159265358979323846264338327950288f
 #define VG_TAUf 6.28318530717958647692528676655900576f
@@ -23,14 +30,9 @@ static inline float vg_signf( float a )
    return a < 0.0f? -1.0f: 1.0f;
 }
 
-static inline float vg_randf(void)
+static inline float vg_fractf( float a )
 {
-   return (float)rand()/(float)(RAND_MAX);
-}
-
-static inline int vg_randint(int max)
-{
-   return rand()%max;
+   return a - floorf( a );
 }
 
 static float stable_force( float current, float diff )
@@ -69,6 +71,11 @@ static inline void v2_copy( v2f a, v2f b )
        b[0] = a[0]; b[1] = a[1];
 }
 
+static inline void v2_zero( v2f a )
+{
+       a[0] = 0.f; a[1] = 0.f;
+}
+
 static inline void v2i_copy( v2i a, v2i b )
 {
        b[0] = a[0]; b[1] = a[1];
@@ -892,29 +899,29 @@ static inline void m4x3_lookat( m4x3f m, v3f pos, v3f target, v3f up )
                                                                { 0.0f, 0.0f, 0.0f, 0.0f }}
 
 static void m4x4_projection( m4x4f m, float angle,
-      float ratio, float near, float far )
+      float ratio, float fnear, float ffar )
 {
-   float scale = tanf( angle * 0.5f * VG_PIf / 180.0f ) * near,
+   float scale = tanf( angle * 0.5f * VG_PIf / 180.0f ) * fnear,
          r = ratio * scale,
          l = -r,
          t = scale,
          b = -t;
 
-   m[0][0] =  2.0f * near / (r - l); 
+   m[0][0] =  2.0f * fnear / (r - l); 
    m[0][1] =  0.0f; 
    m[0][2] =  0.0f; 
    m[0][3] =  0.0f; 
    m[1][0] =  0.0f; 
-   m[1][1] =  2.0f * near / (t - b); 
+   m[1][1] =  2.0f * fnear / (t - b); 
    m[1][2] =  0.0f; 
    m[1][3] =  0.0f; 
    m[2][0] =  (r + l) / (r - l); 
    m[2][1] =  (t + b) / (t - b); 
-   m[2][2] = -(far + near) / (far - near); 
+   m[2][2] = -(ffar + fnear) / (ffar - fnear); 
    m[2][3] = -1.0f; 
    m[3][0] =  0.0f; 
    m[3][1] =  0.0f; 
-   m[3][2] = -2.0f * far * near / (far - near); 
+   m[3][2] = -2.0f * ffar * fnear / (ffar - fnear); 
    m[3][3] =  0.0f;
 } 
 
@@ -1164,6 +1171,12 @@ static inline void q_inv( v4f q, v4f d )
    d[3] =  q[3]*s;
 }
 
+static inline void q_nlerp( v4f a, v4f b, float t, v4f d )
+{
+   v4_lerp( a, b, t, d );
+   q_normalize( d );
+}
+
 static inline void q_m3x3( v4f q, m3x3f d )
 {
    float
@@ -1272,3 +1285,33 @@ static int ray_tri( v3f tri[3], v3f co, v3f dir, float *dist )
    }
    else return 0;
 }
+
+static inline float vg_randf(void)
+{
+   return (float)rand()/(float)(RAND_MAX);
+}
+
+static inline void vg_rand_dir(v3f dir)
+{
+   dir[0] = vg_randf();
+   dir[1] = vg_randf();
+   dir[2] = vg_randf();
+
+   v3_muls( dir, 2.0f, dir );
+   v3_sub( dir, (v3f){1.0f,1.0f,1.0f}, dir );
+
+   v3_normalize( dir );
+}
+
+static inline void vg_rand_sphere( v3f co )
+{
+   vg_rand_dir(co);
+   v3_muls( co, cbrtf( vg_randf() ), co );
+}
+
+static inline int vg_randint(int max)
+{
+   return rand()%max;
+}
+
+#endif /* VG_M_H */