X-Git-Url: https://harrygodden.com/git/?a=blobdiff_plain;f=vg_m.h;h=68e2304a339c13013eae62c3dd3644a62ae6118e;hb=7a1b2ba3172f9f296df110997e5b8cca5f10ab68;hp=0ded4e127302bfd0d396f14416c12710eeb3fb84;hpb=c14db510e727e91cd0041f73663ef5b7ca32e05f;p=vg.git diff --git a/vg_m.h b/vg_m.h index 0ded4e1..68e2304 100644 --- a/vg_m.h +++ b/vg_m.h @@ -32,6 +32,7 @@ #define VG_PIf 3.14159265358979323846264338327950288f #define VG_TAUf 6.28318530717958647692528676655900576f + /* * ----------------------------------------------------------------------------- * Section 0. Misc Operations @@ -106,6 +107,41 @@ static inline f32 vg_rad( f32 deg ) return deg * VG_PIf / 180.0f; } +/* angle to reach b from a */ +static f32 vg_angle_diff( f32 a, f32 b ){ + f32 d = fmod(b,VG_TAUf)-fmodf(a,VG_TAUf); + if( fabsf(d) > VG_PIf ) + d = -vg_signf(d) * (VG_TAUf - fabsf(d)); + + return d; +} + +/* + * quantize float to bit count + */ +static u32 vg_quantf( f32 a, u32 bits, f32 min, f32 max ){ + u32 mask = (0x1 << bits) - 1; + return vg_clampf((a - min) * ((f32)mask/(max-min)), 0.0f, mask ); +} + +/* + * un-quantize discreet to float + */ +static f32 vg_dequantf( u32 q, u32 bits, f32 min, f32 max ){ + u32 mask = (0x1 << bits) - 1; + return min + (f32)q * ((max-min) / (f32)mask); +} + +/* https://iquilezles.org/articles/functions/ + * + * Use k to control the stretching of the function. Its maximum, which is 1, + * happens at exactly x = 1/k. + */ +static f32 vg_exp_impulse( f32 x, f32 k ){ + f32 h = k*x; + return h*expf(1.0f-h); +} + /* * ----------------------------------------------------------------------------- * Section 2.a 2D Vectors @@ -514,6 +550,34 @@ static void v3_tangent_basis( v3f n, v3f tx, v3f ty ){ v3_cross( n, tx, ty ); } +/* + * Compute yaw and pitch based of a normalized vector representing forward + * forward: -z + * result -> (YAW,PITCH,0.0) + */ +static void v3_angles( v3f v, v3f out_angles ){ + float yaw = atan2f( v[0], -v[2] ), + pitch = atan2f( + -v[1], + sqrtf( + v[0]*v[0] + v[2]*v[2] + ) + ); + + out_angles[0] = yaw; + out_angles[1] = pitch; + out_angles[2] = 0.0f; +} + +/* + * Compute the forward vector from (YAW,PITCH,ROLL) + * forward: -z + */ +static void v3_angles_vector( v3f angles, v3f out_v ){ + out_v[0] = sinf( angles[0] ) * cosf( angles[1] ); + out_v[1] = -sinf( angles[1] ); + out_v[2] = -cosf( angles[0] ) * cosf( angles[1] ); +} /* * ----------------------------------------------------------------------------- @@ -628,11 +692,11 @@ static inline void q_inv( v4f q, v4f d ) d[3] = q[3]*s; } -static inline void q_nlerp( v4f a, v4f b, f32 t, v4f d ) -{ +static inline void q_nlerp( v4f a, v4f b, f32 t, v4f d ){ if( v4_dot(a,b) < 0.0f ){ - v4_muls( b, -1.0f, d ); - v4_lerp( a, d, t, d ); + v4f c; + v4_muls( b, -1.0f, c ); + v4_lerp( a, c, t, d ); } else v4_lerp( a, b, t, d ); @@ -673,6 +737,10 @@ static void q_mulv( v4f q, v3f v, v3f d ) v3_add( v1, v2, d ); } +static f32 q_dist( v4f q0, v4f q1 ){ + return acosf( 2.0f * v4_dot(q0,q1) -1.0f ); +} + /* * ----------------------------------------------------------------------------- * Section 4.a 2x2 matrices @@ -710,6 +778,16 @@ static inline void m2x2_create_rotation( m2x2f a, f32 theta ) a[1][1] = c; } +static inline void m2x2_mulv( m2x2f m, v2f v, v2f d ) +{ + v2f res; + + res[0] = m[0][0]*v[0] + m[1][0]*v[1]; + res[1] = m[0][1]*v[0] + m[1][1]*v[1]; + + v2_copy( res, d ); +} + /* * ----------------------------------------------------------------------------- * Section 4.b 3x3 matrices @@ -1194,8 +1272,7 @@ static void m4x3_decompose( m4x3f m, v3f co, v4f q, v3f s ) m3x3_q( rot, q ); } -static void m4x3_expand_aabb_point( m4x3f m, boxf box, v3f point ) -{ +static void m4x3_expand_aabb_point( m4x3f m, boxf box, v3f point ){ v3f v; m4x3_mulv( m, point, v ); @@ -1203,26 +1280,19 @@ static void m4x3_expand_aabb_point( m4x3f m, boxf box, v3f point ) v3_maxv( box[1], v, box[1] ); } -static void m4x3_transform_aabb( m4x3f m, boxf box ) -{ +static void m4x3_expand_aabb_aabb( m4x3f m, boxf boxa, boxf boxb ){ v3f a; v3f b; - - v3_copy( box[0], a ); - v3_copy( box[1], b ); - v3_fill( box[0], INFINITY ); - v3_fill( box[1], -INFINITY ); - - m4x3_expand_aabb_point( m, box, (v3f){ a[0], a[1], a[2] } ); - m4x3_expand_aabb_point( m, box, (v3f){ a[0], b[1], a[2] } ); - m4x3_expand_aabb_point( m, box, (v3f){ b[0], b[1], a[2] } ); - m4x3_expand_aabb_point( m, box, (v3f){ b[0], a[1], a[2] } ); - - m4x3_expand_aabb_point( m, box, (v3f){ a[0], a[1], b[2] } ); - m4x3_expand_aabb_point( m, box, (v3f){ a[0], b[1], b[2] } ); - m4x3_expand_aabb_point( m, box, (v3f){ b[0], b[1], b[2] } ); - m4x3_expand_aabb_point( m, box, (v3f){ b[0], a[1], b[2] } ); + v3_copy( boxb[0], a ); + v3_copy( boxb[1], b ); + m4x3_expand_aabb_point( m, boxa, (v3f){ a[0], a[1], a[2] } ); + m4x3_expand_aabb_point( m, boxa, (v3f){ a[0], b[1], a[2] } ); + m4x3_expand_aabb_point( m, boxa, (v3f){ b[0], b[1], a[2] } ); + m4x3_expand_aabb_point( m, boxa, (v3f){ b[0], a[1], a[2] } ); + m4x3_expand_aabb_point( m, boxa, (v3f){ a[0], a[1], b[2] } ); + m4x3_expand_aabb_point( m, boxa, (v3f){ a[0], b[1], b[2] } ); + m4x3_expand_aabb_point( m, boxa, (v3f){ b[0], b[1], b[2] } ); + m4x3_expand_aabb_point( m, boxa, (v3f){ b[0], a[1], b[2] } ); } - static inline void m4x3_lookat( m4x3f m, v3f pos, v3f target, v3f up ) { v3f dir; @@ -1457,8 +1527,7 @@ static int box_within( boxf greater, boxf lesser ) return 0; } -static inline void box_init_inf( boxf box ) -{ +static inline void box_init_inf( boxf box ){ v3_fill( box[0], INFINITY ); v3_fill( box[1], -INFINITY ); } @@ -1545,7 +1614,7 @@ int plane_intersect2( v4f a, v4f b, v3f p, v3f n ) static int plane_segment( v4f plane, v3f a, v3f b, v3f co ) { f32 d0 = v3_dot( a, plane ) - plane[3], - d1 = v3_dot( b, plane ) - plane[3]; + d1 = v3_dot( b, plane ) - plane[3]; if( d0*d1 < 0.0f ) { @@ -1567,6 +1636,17 @@ static inline f64 plane_polarity( f64 p[4], f64 a[3] ) ; } +static f32 ray_plane( v4f plane, v3f co, v3f dir ){ + f32 d = v3_dot( plane, dir ); + if( fabsf(d) > 1e-6f ){ + v3f v0; + v3_muls( plane, plane[3], v0 ); + v3_sub( v0, co, v0 ); + return v3_dot( v0, plane ) / d; + } + else return INFINITY; +} + /* * ----------------------------------------------------------------------------- * Section 5.c Closest point functions @@ -1577,7 +1657,7 @@ static inline f64 plane_polarity( f64 p[4], f64 a[3] ) * These closest point tests were learned from Real-Time Collision Detection by * Christer Ericson */ -VG_STATIC f32 closest_segment_segment( v3f p1, v3f q1, v3f p2, v3f q2, +static f32 closest_segment_segment( v3f p1, v3f q1, v3f p2, v3f q2, f32 *s, f32 *t, v3f c1, v3f c2) { v3f d1,d2,r; @@ -1654,7 +1734,7 @@ VG_STATIC f32 closest_segment_segment( v3f p1, v3f q1, v3f p2, v3f q2, return v3_length2( v0 ); } -VG_STATIC int point_inside_aabb( boxf box, v3f point ) +static int point_inside_aabb( boxf box, v3f point ) { if((point[0]<=box[1][0]) && (point[1]<=box[1][1]) && (point[2]<=box[1][2]) && (point[0]>=box[0][0]) && (point[1]>=box[0][1]) && (point[2]>=box[0][2]) ) @@ -1663,13 +1743,13 @@ VG_STATIC int point_inside_aabb( boxf box, v3f point ) return 0; } -VG_STATIC void closest_point_aabb( v3f p, boxf box, v3f dest ) +static void closest_point_aabb( v3f p, boxf box, v3f dest ) { v3_maxv( p, box[0], dest ); v3_minv( dest, box[1], dest ); } -VG_STATIC void closest_point_obb( v3f p, boxf box, +static void closest_point_obb( v3f p, boxf box, m4x3f mtx, m4x3f inv_mtx, v3f dest ) { v3f local; @@ -1678,7 +1758,7 @@ VG_STATIC void closest_point_obb( v3f p, boxf box, m4x3_mulv( mtx, local, dest ); } -VG_STATIC f32 closest_point_segment( v3f a, v3f b, v3f point, v3f dest ) +static f32 closest_point_segment( v3f a, v3f b, v3f point, v3f dest ) { v3f v0, v1; v3_sub( b, a, v0 ); @@ -1690,7 +1770,7 @@ VG_STATIC f32 closest_point_segment( v3f a, v3f b, v3f point, v3f dest ) return t; } -VG_STATIC void closest_on_triangle( v3f p, v3f tri[3], v3f dest ) +static void closest_on_triangle( v3f p, v3f tri[3], v3f dest ) { v3f ab, ac, ap; f32 d1, d2; @@ -1786,7 +1866,7 @@ enum contact_type k_contact_type_edge }; -VG_STATIC enum contact_type closest_on_triangle_1( v3f p, v3f tri[3], v3f dest ) +static enum contact_type closest_on_triangle_1( v3f p, v3f tri[3], v3f dest ) { v3f ab, ac, ap; f32 d1, d2; @@ -2197,59 +2277,55 @@ static float vg_sphere_volume( float radius ){ /* changes to STATE_VECTOR_LENGTH also require changes to this */ #define MT_STATE_VECTOR_M 397 -struct { +typedef struct vg_rand vg_rand; +struct vg_rand { u32 mt[MT_STATE_VECTOR_LENGTH]; i32 index; -} -static vg_rand; +}; -static void vg_rand_seed( unsigned long seed ) -{ +static void vg_rand_seed( vg_rand *rand, unsigned long seed ) { /* set initial seeds to mt[STATE_VECTOR_LENGTH] using the generator * from Line 25 of Table 1 in: Donald Knuth, "The Art of Computer * Programming," Vol. 2 (2nd Ed.) pp.102. */ - vg_rand.mt[0] = seed & 0xffffffff; - for( vg_rand.index=1; vg_rand.indexmt[0] = seed & 0xffffffff; + for( rand->index=1; rand->indexindex++){ + rand->mt[rand->index] = (6069 * rand->mt[rand->index-1]) & 0xffffffff; } } /* * Generates a pseudo-randomly generated long. */ -static u32 vg_randu32(void) -{ +static u32 vg_randu32( vg_rand *rand ) { u32 y; /* mag[x] = x * 0x9908b0df for x = 0,1 */ static u32 mag[2] = {0x0, 0x9908b0df}; - if( vg_rand.index >= MT_STATE_VECTOR_LENGTH || vg_rand.index < 0 ){ + if( rand->index >= MT_STATE_VECTOR_LENGTH || rand->index < 0 ){ /* generate STATE_VECTOR_LENGTH words at a time */ int kk; - if( vg_rand.index >= MT_STATE_VECTOR_LENGTH+1 || vg_rand.index < 0 ){ - vg_rand_seed( 4357 ); + if( rand->index >= MT_STATE_VECTOR_LENGTH+1 || rand->index < 0 ){ + vg_rand_seed( rand, 4357 ); } for( kk=0; kk> 1) ^ mag[y & 0x1]; + y = (rand->mt[kk] & MT_UPPER_MASK) | + (rand->mt[kk+1] & MT_LOWER_MASK); + rand->mt[kk] = rand->mt[kk+MT_STATE_VECTOR_M] ^ (y>>1) ^ mag[y & 0x1]; } for( ; kkmt[kk] & MT_UPPER_MASK) | + (rand->mt[kk+1] & MT_LOWER_MASK); + rand->mt[kk] = + rand->mt[ kk+(MT_STATE_VECTOR_M-MT_STATE_VECTOR_LENGTH)] ^ (y >> 1) ^ mag[y & 0x1]; } - y = (vg_rand.mt[MT_STATE_VECTOR_LENGTH-1] & MT_UPPER_MASK) | - (vg_rand.mt[0] & MT_LOWER_MASK); - vg_rand.mt[MT_STATE_VECTOR_LENGTH-1] = - vg_rand.mt[MT_STATE_VECTOR_M-1] ^ (y >> 1) ^ mag[y & 0x1]; - vg_rand.index = 0; + y = (rand->mt[MT_STATE_VECTOR_LENGTH-1] & MT_UPPER_MASK) | + (rand->mt[0] & MT_LOWER_MASK); + rand->mt[MT_STATE_VECTOR_LENGTH-1] = + rand->mt[MT_STATE_VECTOR_M-1] ^ (y >> 1) ^ mag[y & 0x1]; + rand->index = 0; } - y = vg_rand.mt[vg_rand.index++]; + y = rand->mt[rand->index++]; y ^= (y >> 11); y ^= (y << 7) & MT_TEMPERING_MASK_B; y ^= (y << 15) & MT_TEMPERING_MASK_C; @@ -2260,21 +2336,21 @@ static u32 vg_randu32(void) /* * Generates a pseudo-randomly generated f64 in the range [0..1]. */ -static inline f64 vg_randf64(void) -{ - return (f64)vg_randu32()/(f64)0xffffffff; +static inline f64 vg_randf64( vg_rand *rand ){ + return (f64)vg_randu32(rand)/(f64)0xffffffff; } -static inline f64 vg_randf64_range( f64 min, f64 max ) -{ - return vg_lerp( min, max, (f64)vg_randf64() ); +static inline f64 vg_randf64_range( vg_rand *rand, f64 min, f64 max ){ + return vg_lerp( min, max, (f64)vg_randf64(rand) ); } -static inline void vg_rand_dir( v3f dir ) -{ - dir[0] = vg_randf64(); - dir[1] = vg_randf64(); - dir[2] = vg_randf64(); +static inline void vg_rand_dir( vg_rand *rand, v3f dir ){ + dir[0] = vg_randf64(rand); + dir[1] = vg_randf64(rand); + dir[2] = vg_randf64(rand); + + /* warning: *could* be 0 length. + * very unlikely.. 1 in (2^32)^3. but its mathematically wrong. */ v3_muls( dir, 2.0f, dir ); v3_sub( dir, (v3f){1.0f,1.0f,1.0f}, dir ); @@ -2282,10 +2358,25 @@ static inline void vg_rand_dir( v3f dir ) v3_normalize( dir ); } -static inline void vg_rand_sphere( v3f co ) -{ - vg_rand_dir(co); - v3_muls( co, cbrtf( vg_randf64() ), co ); +static inline void vg_rand_sphere( vg_rand *rand, v3f co ){ + vg_rand_dir(rand,co); + v3_muls( co, cbrtf( vg_randf64(rand) ), co ); +} + +static void vg_rand_disc( vg_rand *rand, v2f co ){ + f32 a = vg_randf64(rand) * VG_TAUf; + co[0] = sinf(a); + co[1] = cosf(a); + v2_muls( co, sqrtf( vg_randf64(rand) ), co ); +} + +static void vg_rand_cone( vg_rand *rand, v3f out_dir, f32 angle ){ + f32 r = sqrtf(vg_randf64(rand)) * angle * 0.5f, + a = vg_randf64(rand) * VG_TAUf; + + out_dir[0] = sinf(a) * sinf(r); + out_dir[1] = cosf(a) * sinf(r); + out_dir[2] = cosf(r); } #endif /* VG_M_H */