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#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)
#define SIGN(x) (x < 0 ? -1 : 1)
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;
float length() {
return sqrtf(x * x + y * y + z * z);
}
Vector3 operator+(const Vector3& other) {
return { x + other.x, y + other.y, z + other.z };
}
};
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;
}
Mat4x4 getXRotationMatrix(float angleRadians) {
return {
{ 1, 0, 0, 0,
0, cos(angleRadians), -sin(angleRadians), 0,
0, sin(angleRadians), cos(angleRadians), 0,
0, 0, 0, 1 }
};
}
Mat4x4 getYRotationMatrix(float angleRadians) {
return {
{ cos(angleRadians), 0, sin(angleRadians), 0,
0, 1, 0, 0,
-sin(angleRadians), 0, cos(angleRadians), 0,
0, 0, 0, 1 }
};
}
Mat4x4 getZRotationMatrix(float angleRadians) {
return {
{ cos(angleRadians), -sin(angleRadians), 0, 0,
sin(angleRadians), cos(angleRadians), 0, 0,
0, 0, 1, 0,
0, 0, 0, 1 }
};
}
Mat4x4 rotate(float xRadians, float yRadians, float zRadians) {
Mat4x4 result = copy();
Mat4x4 rotationMatrix;
if (xRadians != 0) {
rotationMatrix = getXRotationMatrix(xRadians);
result = result * rotationMatrix;
}
if (yRadians != 0) {
rotationMatrix = getYRotationMatrix(yRadians);
result = result * rotationMatrix;
}
if (zRadians != 0) {
rotationMatrix = getZRotationMatrix(zRadians);
result = result * rotationMatrix;
}
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 multMat4x4(const Mat4x4& other) {
Mat4x4 result;
for (int i = 0; i < 4; ++i) {
for (int j = 0; j < 4; ++j) {
int row = i * 4;
result.m[row + j] = m[row + 0] * other.m[0 + j] + m[row + 1] * other.m[4 + j] + m[row + 2] * other.m[8 + j] + m[row + 3] * other.m[12 + j];
}
}
return result;
}
Mat4x4 operator*(const Mat4x4& other) {
return multMat4x4(other);
}
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;
}
Mat4x4 getPerspectiveProjection(float near, float far, float fieldOfViewRadians, float aspectRatio) {
float halfFieldOfView = fieldOfViewRadians * 0.5f;
float top = tan(halfFieldOfView) * near;
float bottom = -top;
float right = top * aspectRatio;
float left = -right;
return {
{ (2 * near) / (right - left), 0, 0, 0,
0, (2 * near) / (top - bottom), 0, 0,
(right + left) / (right - left), (top + bottom) / (top - bottom), -(far + near) / (far - near), -1,
0, 0, (-2 * far * near) / (far - near), 0 }
};
}
void print() {
printf("[ ");
for (int idx = 0; idx < 16; idx++) {
printf("%f, ", m[idx]);
}
printf(" ]\n");
}
};
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