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-rw-r--r--util.c303
1 files changed, 4 insertions, 299 deletions
diff --git a/util.c b/util.c
index 0c1c1c3..9216bd1 100644
--- a/util.c
+++ b/util.c
@@ -606,15 +606,6 @@ float randf(void) {
return (float)rand() / (float)((ulong)RAND_MAX + 1);
}
-float rand_gauss(void) {
- // https://en.wikipedia.org/wiki/Normal_distribution#Generating_values_from_normal_distribution
- float U, V;
- do
- U = randf(), V = randf();
- while (U == 0 || V == 0);
- return sqrtf(-2 * logf(U)) * cosf(TAUf * V);
-}
-
u32 rand_u32(void) {
return ((u32)rand() & 0xfff)
| ((u32)rand() & 0xfff) << 12
@@ -724,96 +715,6 @@ v2 v2_polar(float r, float theta) {
return V2(r * cosf(theta), r * sinf(theta));
}
-v3 V3(float x, float y, float z) {
- v3 v;
- v.x = x;
- v.y = y;
- v.z = z;
- return v;
-}
-
-v3 v3_from_v2(v2 v) {
- return V3(v.x, v.y, 0);
-}
-
-v3 v3_add(v3 a, v3 b) {
- return V3(a.x + b.x, a.y + b.y, a.z + b.z);
-}
-
-v3 v3_sub(v3 a, v3 b) {
- return V3(a.x - b.x, a.y - b.y, a.z - b.z);
-}
-
-v3 v3_scale(v3 v, float s) {
- return V3(v.x * s, v.y * s, v.z * s);
-}
-
-v3 v3_lerp(float x, v3 a, v3 b) {
- return V3(lerpf(x, a.x, b.x), lerpf(x, a.y, b.y), lerpf(x, a.z, b.z));
-}
-
-float v3_dot(v3 u, v3 v) {
- return u.x*v.x + u.y*v.y + u.z*v.z;
-}
-
-v3 v3_cross(v3 u, v3 v) {
- v3 prod = V3(u.y*v.z - u.z*v.y, u.z*v.x - u.x*v.z, u.x*v.y - u.y*v.x);
- return prod;
-}
-
-float v3_len(v3 v) {
- return sqrtf(v3_dot(v, v));
-}
-
-float v3_dist(v3 a, v3 b) {
- return v3_len(v3_sub(a, b));
-}
-
-float v3_dist_squared(v3 a, v3 b) {
- v3 diff = v3_sub(a, b);
- return v3_dot(diff, diff);
-}
-
-v3 v3_normalize(v3 v) {
- float len = v3_len(v);
- float mul = len == 0.0f ? 1.0f : 1.0f/len;
- return v3_scale(v, mul);
-}
-
-v2 v3_xy(v3 v) {
- return V2(v.x, v.y);
-}
-
-// a point on a unit sphere
-v3 v3_on_sphere(float yaw, float pitch) {
- return V3(cosf(yaw) * cosf(pitch), sinf(pitch), sinf(yaw) * cosf(pitch));
-}
-
-void v3_print(v3 v) {
- printf("(%f, %f, %f)\n", v.x, v.y, v.z);
-}
-
-v3 v3_rand(void) {
- return V3(randf(), randf(), randf());
-}
-
-v3 v3_rand_unit(void) {
- /*
- monte carlo method
- keep generating random points in cube of radius 1 (width 2) centered at origin,
- until you get a point in the unit sphere, then extend it to find the point lying
- on the sphere.
- */
- while (1) {
- v3 v = V3(rand_uniform(-1.0f, +1.0f), rand_uniform(-1.0f, +1.0f), rand_uniform(-1.0f, +1.0f));
- float dist_squared_to_origin = v3_dot(v, v);
- if (dist_squared_to_origin <= 1 && dist_squared_to_origin != 0.0f) {
- return v3_scale(v, 1.0f / sqrtf(dist_squared_to_origin));
- }
- }
- return V3(0, 0, 0);
-}
-
v4 V4(float x, float y, float z, float w) {
v4 v;
v.x = x;
@@ -823,207 +724,11 @@ v4 V4(float x, float y, float z, float w) {
return v;
}
-v4 v4_add(v4 a, v4 b) {
- return V4(a.x + b.x, a.y + b.y, a.z + b.z, a.w + b.w);
-}
-
-v4 v4_sub(v4 a, v4 b) {
- return V4(a.x - b.x, a.y - b.y, a.z - b.z, a.w - b.w);
-}
-
-v4 v4_scale(v4 v, float s) {
- return V4(v.x * s, v.y * s, v.z * s, v.w * s);
-}
-
-v4 v4_scale_xyz(v4 v, float s) {
- return V4(v.x * s, v.y * s, v.z * s, v.w);
-}
-
-v4 v4_lerp(float x, v4 a, v4 b) {
- return V4(lerpf(x, a.x, b.x), lerpf(x, a.y, b.y), lerpf(x, a.z, b.z), lerpf(x, a.w, b.w));
-}
-
-float v4_dot(v4 u, v4 v) {
- return u.x*v.x + u.y*v.y + u.z*v.z + u.w*v.w;
-}
-
-// create a new vector by multiplying the respective components of u and v
-v4 v4_mul(v4 u, v4 v) {
- return V4(u.x * v.x, u.y * v.y, u.z * v.z, u.w * v.w);
-}
-
-float v4_len(v4 v) {
- return sqrtf(v4_dot(v, v));
-}
-
-v4 v4_normalize(v4 v) {
- float len = v4_len(v);
- float mul = len == 0.0f ? 1.0f : 1.0f/len;
- return v4_scale(v, mul);
-}
-
-v3 v4_xyz(v4 v) {
- return V3(v.x, v.y, v.z);
-}
-
-v4 v4_rand(void) {
- return V4(randf(), randf(), randf(), randf());
-}
-
-void v4_print(v4 v) {
- printf("(%f, %f, %f, %f)\n", v.x, v.y, v.z, v.w);
-}
-
-
v2d V2D(double x, double y) {
- v2d v;
- v.x = x;
- v.y = y;
- return v;
-}
-
-void m4_print(m4 m) {
- int i;
- for (i = 0; i < 4; ++i)
- printf("[ %f %f %f %f ]\n", m.e[i], m.e[i+4], m.e[i+8], m.e[i+12]);
- printf("\n");
-}
-
-m4 M4(
- float a, float b, float c, float d,
- float e, float f, float g, float h,
- float i, float j, float k, float l,
- float m, float n, float o, float p) {
- m4 ret;
- float *x = ret.e;
- x[0] = a; x[4] = b; x[ 8] = c; x[12] = d;
- x[1] = e; x[5] = f; x[ 9] = g; x[13] = h;
- x[2] = i; x[6] = j; x[10] = k; x[14] = l;
- x[3] = m; x[7] = n; x[11] = o; x[15] = p;
- return ret;
-}
-
-// see https://en.wikipedia.org/wiki/Rotation_matrix#General_rotations
-m4 m4_yaw(float yaw) {
- float c = cosf(yaw), s = sinf(yaw);
- return M4(
- c, 0, -s, 0,
- 0, 1, 0, 0,
- s, 0, c, 0,
- 0, 0, 0, 1
- );
-}
-
-m4 m4_pitch(float pitch) {
- float c = cosf(pitch), s = sinf(pitch);
- return M4(
- 1, 0, 0, 0,
- 0, c, -s, 0,
- 0, s, c, 0,
- 0, 0, 0, 1
- );
-}
-
-// https://en.wikipedia.org/wiki/Translation_(geometry)
-m4 m4_translate(v3 t) {
- return M4(
- 1, 0, 0, t.x,
- 0, 1, 0, t.y,
- 0, 0, 1, t.z,
- 0, 0, 0, 1
- );
-}
-
-// multiply m by [v.x, v.y, v.z, 1]
-v3 m4_mul_v3(m4 m, v3 v) {
- return v3_add(v3_scale(V3(m.e[0], m.e[1], m.e[2]), v.x), v3_add(v3_scale(V3(m.e[4], m.e[5], m.e[6]), v.y),
- v3_add(v3_scale(V3(m.e[8], m.e[9], m.e[10]), v.z), V3(m.e[12], m.e[13], m.e[14]))));
-}
-
-/*
-4x4 perspective matrix.
-fov - field of view in radians, aspect - width:height aspect ratio, z_near/z_far - clipping planes
-math stolen from gluPerspective (https://www.khronos.org/registry/OpenGL-Refpages/gl2.1/xhtml/gluPerspective.xml)
-*/
-m4 m4_perspective(float fov, float aspect, float z_near, float z_far) {
- float f = 1.0f / tanf(fov / 2.0f);
- return M4(
- f/aspect, 0, 0, 0,
- 0, f, 0, 0,
- 0, 0, (z_far+z_near) / (z_near-z_far), (2.0f*z_far*z_near) / (z_near-z_far),
- 0, 0, -1, 0
- );
-}
-
-// windows.h defines near and far, so let's not use those
-m4 m4_ortho(float left, float right, float bottom, float top, float near_, float far_) {
- float tx = -(right + left)/(right - left);
- float ty = -(top + bottom)/(top - bottom);
- float tz = -(far_ + near_)/(far_ - near_);
- return M4(
- 2.0f / (right - left), 0, 0, tx,
- 0, 2.0f / (top - bottom), 0, ty,
- 0, 0, -2.0f / (far_ - near_), tz,
- 0, 0, 0, 1
- );
-}
-
-
-m4 m4_mul(m4 a, m4 b) {
- m4 prod = {0};
- int i, j;
- float *x = prod.e;
- for (i = 0; i < 4; ++i) {
- for (j = 0; j < 4; ++j, ++x) {
- float *as = &a.e[j];
- float *bs = &b.e[4*i];
- *x = as[0]*bs[0] + as[4]*bs[1] + as[8]*bs[2] + as[12]*bs[3];
- }
- }
- return prod;
-}
-
-m4 m4_inv(m4 mat) {
- m4 ret;
- float *inv = ret.e;
- float *m = mat.e;
-
- inv[0] = m[5] * m[10] * m[15] - m[5] * m[11] * m[14] - m[9] * m[6] * m[15] + m[9] * m[7] * m[14] + m[13] * m[6] * m[11] - m[13] * m[7] * m[10];
- inv[4] = -m[4] * m[10] * m[15] + m[4] * m[11] * m[14] + m[8] * m[6] * m[15] - m[8] * m[7] * m[14] - m[12] * m[6] * m[11] + m[12] * m[7] * m[10];
- inv[8] = m[4] * m[9] * m[15] - m[4] * m[11] * m[13] - m[8] * m[5] * m[15] + m[8] * m[7] * m[13] + m[12] * m[5] * m[11] - m[12] * m[7] * m[9];
- inv[12] = -m[4] * m[9] * m[14] + m[4] * m[10] * m[13] + m[8] * m[5] * m[14] - m[8] * m[6] * m[13] - m[12] * m[5] * m[10] + m[12] * m[6] * m[9];
- inv[1] = -m[1] * m[10] * m[15] + m[1] * m[11] * m[14] + m[9] * m[2] * m[15] - m[9] * m[3] * m[14] - m[13] * m[2] * m[11] + m[13] * m[3] * m[10];
- inv[5] = m[0] * m[10] * m[15] - m[0] * m[11] * m[14] - m[8] * m[2] * m[15] + m[8] * m[3] * m[14] + m[12] * m[2] * m[11] - m[12] * m[3] * m[10];
- inv[9] = -m[0] * m[9] * m[15] + m[0] * m[11] * m[13] + m[8] * m[1] * m[15] - m[8] * m[3] * m[13] - m[12] * m[1] * m[11] + m[12] * m[3] * m[9];
- inv[13] = m[0] * m[9] * m[14] - m[0] * m[10] * m[13] - m[8] * m[1] * m[14] + m[8] * m[2] * m[13] + m[12] * m[1] * m[10] - m[12] * m[2] * m[9];
- inv[2] = m[1] * m[6] * m[15] - m[1] * m[7] * m[14] - m[5] * m[2] * m[15] + m[5] * m[3] * m[14] + m[13] * m[2] * m[7] - m[13] * m[3] * m[6];
- inv[6] = -m[0] * m[6] * m[15] + m[0] * m[7] * m[14] + m[4] * m[2] * m[15] - m[4] * m[3] * m[14] - m[12] * m[2] * m[7] + m[12] * m[3] * m[6];
- inv[10] = m[0] * m[5] * m[15] - m[0] * m[7] * m[13] - m[4] * m[1] * m[15] + m[4] * m[3] * m[13] + m[12] * m[1] * m[7] - m[12] * m[3] * m[5];
- inv[14] = -m[0] * m[5] * m[14] + m[0] * m[6] * m[13] + m[4] * m[1] * m[14] - m[4] * m[2] * m[13] - m[12] * m[1] * m[6] + m[12] * m[2] * m[5];
- inv[3] = -m[1] * m[6] * m[11] + m[1] * m[7] * m[10] + m[5] * m[2] * m[11] - m[5] * m[3] * m[10] - m[9] * m[2] * m[7] + m[9] * m[3] * m[6];
- inv[7] = m[0] * m[6] * m[11] - m[0] * m[7] * m[10] - m[4] * m[2] * m[11] + m[4] * m[3] * m[10] + m[8] * m[2] * m[7] - m[8] * m[3] * m[6];
- inv[11] = -m[0] * m[5] * m[11] + m[0] * m[7] * m[9] + m[4] * m[1] * m[11] - m[4] * m[3] * m[9] - m[8] * m[1] * m[7] + m[8] * m[3] * m[5];
- inv[15] = m[0] * m[5] * m[10] - m[0] * m[6] * m[9] - m[4] * m[1] * m[10] + m[4] * m[2] * m[9] + m[8] * m[1] * m[6] - m[8] * m[2] * m[5];
-
- float det = m[0] * inv[0] + m[1] * inv[4] + m[2] * inv[8] + m[3] * inv[12];
-
- if (det == 0) {
- memset(inv, 0, sizeof *inv);
- } else {
- det = 1 / det;
-
- for (int i = 0; i < 16; i++)
- inv[i] *= det;
- }
-
- return ret;
-}
-
-v2i V2I(int x, int y) {
- v2i v;
- v.x = x;
- v.y = y;
- return v;
+ return (v2d) {
+ .x = x,
+ .y = y
+ };
}
void rgba_u32_to_floats(u32 rgba, float floats[4]) {