diff options
author | Matthew Kosarek <mattkae@protonmail.com> | 2021-05-16 19:50:15 -0400 |
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committer | Matthew Kosarek <mattkae@protonmail.com> | 2021-05-16 19:50:15 -0400 |
commit | a00c0aab1eb5a7a55bef8ca08115bdd722ab5699 (patch) | |
tree | 45b5c4cc8c380d0630a8e0185af7229f26dc754a /shared_cpp/mathlib.h | |
parent | 4941a1874b6ca9d142d94df70b2aec5e0b35b94e (diff) |
Moved the frontend directory up so that it no longer exists
Diffstat (limited to 'shared_cpp/mathlib.h')
-rw-r--r-- | shared_cpp/mathlib.h | 227 |
1 files changed, 227 insertions, 0 deletions
diff --git a/shared_cpp/mathlib.h b/shared_cpp/mathlib.h new file mode 100644 index 0000000..3ed61cd --- /dev/null +++ b/shared_cpp/mathlib.h @@ -0,0 +1,227 @@ +#pragma once +#include <cstdio> +#include <cstdlib> +#include <cstring> +#include <cmath> + +#define MAX(x, y) (((x) > (y)) ? (x) : (y)) +#define MIN(x, y) (((x) < (y)) ? (x) : (y)) +#define ABS(x) (x < 0 ? -x : x) + +struct Vector2 { + float x = 0; + float y = 0; + + Vector2 operator+(Vector2 other) { + return { x + other.x, y + other.y }; + } + + Vector2& operator+=(Vector2 other) { + x += other.x; + y += other.y; + return *this; + } + + Vector2 operator-(Vector2 other) { + return { x - other.x, y - other.y }; + } + + Vector2 operator*(float s) { + return { x * s, y * s }; + } + + Vector2 operator/(float s) { + return { x / s, y / s }; + } + + float dot(Vector2 other) { + return x * other.x + y * other.y; + } + + float length() { + return sqrtf(x * x + y * y); + } + + Vector2 normalize() { + float len = length(); + float inverseLength = len == 0 ? 1.0 : 1.0 / len; + + return { x * inverseLength, y * inverseLength }; + } + + Vector2 negate() { + return { -x, -y }; + } + + Vector2 getPerp() { + return { y, -x }; + } + + Vector2 rotate(float angle) { + return { + x * cosf(angle) - y * sinf(angle), + x * sinf(angle) + y * cosf(angle) + }; + } + + void printDebug(const char* name) { + printf("%s=Vector2(%f, %f)\n", name, x, y); + } + + float determinant(Vector2 other) { + // + // [ a b ] + // [ c d ] + // + // [ x other.x ] + // [ y other.y ] + // + // det = a * d - b * c + // det = x * other.y - other.x * y + // + return x * other.y - other.x * y; + } +}; + +struct Vector3 { + float x = 0.f; + float y = 0.f; + float z = 0.f; +}; + +struct Vector4 { + float x = 0.f; + float y = 0.f; + float z = 0.f; + float w = 0.f; + + float length() { + return sqrtf(x * x + y * y + z * z + w * w); + } + + Vector4 normalize() { + float len = length(); + float inverseLength = len == 0 ? 1.0 : 1.0 / len; + + return { x * inverseLength, y * inverseLength, z * inverseLength, w * inverseLength }; + } + + Vector4 fromColor(float r, float g, float b, float a) { + float scale = 1.f / 255.f; + return { r * scale, g * scale, b * scale, a * scale }; + } + + Vector4 toNormalizedColor() { + return fromColor(x, y, z, w); + } +}; + +struct Mat4x4 { + float m[16] = { + 1, 0, 0, 0, + 0, 1, 0, 0, + 0, 0, 1, 0, + 0, 0, 0, 1 + }; + + Mat4x4 copy() { + Mat4x4 result; + memcpy(result.m, m, sizeof(float) * 16); + return result; + } + + Mat4x4 scale(Vector3 v) { + Mat4x4 result = copy(); + result.m[0] = result.m[0] * v.x; + result.m[5] = result.m[5] *v.y; + result.m[10] = result.m[10] * v.z; + return result; + } + + Mat4x4 translate(Vector3 v) { + Mat4x4 result = copy(); + result.m[12] += v.x; + result.m[13] += v.y; + result.m[14] += v.z; + return result; + } + + Mat4x4 translateByVec2(Vector2 v) { + Mat4x4 result = copy(); + result.m[12] += v.x; + result.m[13] += v.y; + return result; + } + + Mat4x4 rotate2D(float angle) { + Mat4x4 result = copy(); + result.m[0] = cos(angle); + result.m[1] = -sin(angle); + result.m[4] = sin(angle); + result.m[5] = cos(angle); + return result; + } + + Vector2 multByVec2(Vector2 v) { + Vector4 vec4 = { v.x, v.y, 0.0, 1.0 }; + return { + vec4.x * m[0] + vec4.y * m[4] + vec4.z * m[8] + vec4.w * m[12], + vec4.x * m[1] + vec4.y * m[5] + vec4.z * m[9] + vec4.w * m[13] + }; + } + + Vector2 operator*(Vector2 v) { + return multByVec2(v); + } + + Mat4x4 getOrthographicMatrix(float left, float right, float bottom, float top) { + Mat4x4 result; + result.m[0] = 2.0 / (right - left); + result.m[5] = 2.0 / (top - bottom); + result.m[10] = 1.0; + result.m[12] = -(right + left) / (right - left); + result.m[13] = -(top + bottom) / (top - bottom); + return result; + } + + Mat4x4 inverse() { + Mat4x4 inv; + + inv.m[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.m[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.m[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.m[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.m[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.m[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.m[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.m[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.m[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.m[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.m[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.m[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.m[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.m[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.m[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.m[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.m[0] + m[1] * inv.m[4] + m[2] * inv.m[8] + m[3] * inv.m[12]; + + if (det == 0) + return Mat4x4(); + + det = 1.f / det; + + for (int i = 0; i < 16; i++) + inv.m[i] = inv.m[i] * det; + + return inv; + } + + void print() { + printf("[ "); + for (int idx = 0; idx < 16; idx++) { + printf("%f, ", m[idx]); + } + printf(" ]\n"); + } +}; |