remove a bunch of unused math functions

2 files changed, 4 insertions, 397 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]) {
diff --git a/util.h b/util.h
index 99d8128..4cfcc04 100644
--- a/util.h
+++ b/util.h
@@ -28,29 +28,11 @@ typedef struct {
 	float x, y;
 } v2;
 typedef struct {
-	float x, y, z;
-} v3;
-typedef struct {
 	float x, y, z, w;
 } v4;
 typedef struct {
 	double x, y;
 } v2d;
-typedef struct {
-	int x, y;
-} v2i;
-
-// matrices are column-major, because that's what they are in OpenGL 
-typedef struct {
-	float e[16];
-} m4;
-
-static const m4 m4_identity = {{
-	1, 0, 0, 0,
-	0, 1, 0, 0,
-	0, 0, 1, 0,
-	0, 0, 0, 1
-}};
 
 typedef struct {
 	v2 pos, size;
@@ -172,7 +154,6 @@ i64 sgn_i64(i64 x);
 float sgnf(float x);
 float smoothstepf(float x);
 float randf(void);
-float rand_gauss(void);
 u32 rand_u32(void);
 float rand_uniform(float from, float to);
 float sigmoidf(float x);
@@ -194,47 +175,7 @@ float v2_dist_squared(v2 a, v2 b);
 void v2_print(v2 v);
 v2 v2_rand_unit(void);
 v2 v2_polar(float r, float theta);
-v3 V3(float x, float y, float z);
-v3 v3_from_v2(v2 v);
-v3 v3_add(v3 a, v3 b);
-v3 v3_sub(v3 a, v3 b);
-v3 v3_scale(v3 v, float s);
-v3 v3_lerp(float x, v3 a, v3 b);
-float v3_dot(v3 u, v3 v);
-v3 v3_cross(v3 u, v3 v);
-float v3_len(v3 v);
-float v3_dist(v3 a, v3 b);
-float v3_dist_squared(v3 a, v3 b);
-v3 v3_normalize(v3 v);
-v2 v3_xy(v3 v);
-v3 v3_on_sphere(float yaw, float pitch);
-void v3_print(v3 v);
-v3 v3_rand(void);
-v3 v3_rand_unit(void);
 v4 V4(float x, float y, float z, float w);
-v4 v4_add(v4 a, v4 b);
-v4 v4_sub(v4 a, v4 b);
-v4 v4_scale(v4 v, float s);
-v4 v4_scale_xyz(v4 v, float s);
-v4 v4_lerp(float x, v4 a, v4 b);
-float v4_dot(v4 u, v4 v);
-v4 v4_mul(v4 u, v4 v);
-float v4_len(v4 v);
-v4 v4_normalize(v4 v);
-v3 v4_xyz(v4 v);
-v4 v4_rand(void);
-void v4_print(v4 v);
-v2d V2D(double x, double y);
-void m4_print(m4 m);
-m4 m4_yaw(float yaw);
-m4 m4_pitch(float pitch);
-m4 m4_translate(v3 t);
-v3 m4_mul_v3(m4 m, v3 v);
-m4 m4_perspective(float fov, float aspect, float z_near, float z_far);
-m4 m4_ortho(float left, float right, float bottom, float top, float near_, float far_);
-m4 m4_mul(m4 a, m4 b);
-m4 m4_inv(m4 mat);
-v2i V2I(int x, int y);
 void rgba_u32_to_floats(u32 rgba, float floats[4]);
 v4 rgba_u32_to_v4(u32 rgba);
 u32 rgba_v4_to_u32(v4 color);
@@ -354,47 +295,8 @@ float v2_dist_squared(v2 a, v2 b);
 void v2_print(v2 v);
 v2 v2_rand_unit(void);
 v2 v2_polar(float r, float theta);
-v3 V3(float x, float y, float z);
-v3 v3_from_v2(v2 v);
-v3 v3_add(v3 a, v3 b);
-v3 v3_sub(v3 a, v3 b);
-v3 v3_scale(v3 v, float s);
-v3 v3_lerp(float x, v3 a, v3 b);
-float v3_dot(v3 u, v3 v);
-v3 v3_cross(v3 u, v3 v);
-float v3_len(v3 v);
-float v3_dist(v3 a, v3 b);
-float v3_dist_squared(v3 a, v3 b);
-v3 v3_normalize(v3 v);
-v2 v3_xy(v3 v);
-v3 v3_on_sphere(float yaw, float pitch);
-void v3_print(v3 v);
-v3 v3_rand(void);
-v3 v3_rand_unit(void);
 v4 V4(float x, float y, float z, float w);
-v4 v4_add(v4 a, v4 b);
-v4 v4_sub(v4 a, v4 b);
-v4 v4_scale(v4 v, float s);
-v4 v4_scale_xyz(v4 v, float s);
-v4 v4_lerp(float x, v4 a, v4 b);
-float v4_dot(v4 u, v4 v);
-v4 v4_mul(v4 u, v4 v);
-float v4_len(v4 v);
-v4 v4_normalize(v4 v);
-v3 v4_xyz(v4 v);
-v4 v4_rand(void);
-void v4_print(v4 v);
 v2d V2D(double x, double y);
-void m4_print(m4 m);
-m4 m4_yaw(float yaw);
-m4 m4_pitch(float pitch);
-m4 m4_translate(v3 t);
-v3 m4_mul_v3(m4 m, v3 v);
-m4 m4_perspective(float fov, float aspect, float z_near, float z_far);
-m4 m4_ortho(float left, float right, float bottom, float top, float near_, float far_);
-m4 m4_mul(m4 a, m4 b);
-m4 m4_inv(m4 mat);
-v2i V2I(int x, int y);
 void rgba_u32_to_floats(u32 rgba, float floats[4]);
 v4 rgba_u32_to_v4(u32 rgba);
 u32 rgba_v4_to_u32(v4 color);