-/* 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
return a - floorf( a );
}
-static inline float vg_randf(void)
-{
- return (float)rand()/(float)(RAND_MAX);
-}
-
-static inline int vg_randint(int max)
-{
- return rand()%max;
-}
-
static float stable_force( float current, float diff )
{
float fnew = current + diff;
return fnew;
}
-#define VG_MIN( A, B ) ((A)<(B)?(A):(B))
-#define VG_MAX( A, B ) ((A)>(B)?(A):(B))
-
static inline int vg_min( int a, int b )
{
return a < b? a: b;
return a + t*(b-a);
}
+static inline double vg_lerp( double a, double b, double t )
+{
+ return a + t*(b-a);
+}
+
+/* correctly lerp around circular period -pi -> pi */
+static float vg_alerpf( float a, float b, float t )
+{
+ float d = fmodf( b-a, VG_TAUf ),
+ s = fmodf( 2.0f*d, VG_TAUf ) - d;
+ return a + s*t;
+}
+
static inline void v3_lerp( v3f a, v3f b, float t, v3f d )
{
d[0] = a[0] + t*(b[0]-a[0]);
v3_negate( b[3], b[3] );
}
+static void m4x3_invert_full( m4x3f src, m4x3f dst )
+{
+ float t2, t4, t5,
+ det,
+ a = src[0][0], b = src[0][1], c = src[0][2],
+ e = src[1][0], f = src[1][1], g = src[1][2],
+ i = src[2][0], j = src[2][1], k = src[2][2],
+ m = src[3][0], n = src[3][1], o = src[3][2];
+
+ t2 = j*o - n*k;
+ t4 = i*o - m*k;
+ t5 = i*n - m*j;
+
+ dst[0][0] = f*k - g*j;
+ dst[1][0] =-(e*k - g*i);
+ dst[2][0] = e*j - f*i;
+ dst[3][0] =-(e*t2 - f*t4 + g*t5);
+
+ dst[0][1] =-(b*k - c*j);
+ dst[1][1] = a*k - c*i;
+ dst[2][1] =-(a*j - b*i);
+ dst[3][1] = a*t2 - b*t4 + c*t5;
+
+ t2 = f*o - n*g;
+ t4 = e*o - m*g;
+ t5 = e*n - m*f;
+
+ dst[0][2] = b*g - c*f ;
+ dst[1][2] =-(a*g - c*e );
+ dst[2][2] = a*f - b*e ;
+ dst[3][2] =-(a*t2 - b*t4 + c * t5);
+
+ det = 1.0f / (a * dst[0][0] + b * dst[1][0] + c * dst[2][0]);
+ v3_muls( dst[0], det, dst[0] );
+ v3_muls( dst[1], det, dst[1] );
+ v3_muls( dst[2], det, dst[2] );
+ v3_muls( dst[3], det, dst[3] );
+}
+
static inline void m4x3_copy( m4x3f a, m4x3f b )
{
v3_copy( a[0], b[0] );
{ 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;
}
d[3] = q[3]*s;
}
+static inline void q_nlerp( v4f a, v4f b, float t, v4f d )
+{
+ if( v4_dot(a,b) < 0.0f )
+ {
+ v4_muls( b, -1.0f, d );
+ v4_lerp( a, d, t, d );
+ }
+ else
+ v4_lerp( a, b, t, d );
+
+ q_normalize( d );
+}
+
static inline void q_m3x3( v4f q, m3x3f d )
{
float
}
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;
+}
+
+static void eval_bezier_time( v3f p0, v3f p1, v3f h0, v3f h1, float t, v3f p )
+{
+ float tt = t*t,
+ ttt = tt*t;
+
+ v3_muls( p1, ttt, p );
+ v3_muladds( p, h1, 3.0f*tt -3.0f*ttt, p );
+ v3_muladds( p, h0, 3.0f*ttt -6.0f*tt +3.0f*t, p );
+ v3_muladds( p, p0, 3.0f*tt -ttt -3.0f*t +1.0f, p );
+}
+
+#endif /* VG_M_H */