function mat4() {
    return [
        1, 0, 0, 0,
        0, 1, 0, 0,
        0, 0, 1, 0,
        0, 0, 0, 1
    ]
}

function orthographic(pLeft, pRight, pBottom, pTop) {
    const lResult = mat4();
    lResult[0] = 2.0 / (pRight - pLeft);
    lResult[5] = 2.0 / (pTop - pBottom);
    lResult[10] = 1.0;
    lResult[12] = -(pRight + pLeft) / (pRight - pLeft);
    lResult[13] = -(pTop + pBottom) / (pTop - pBottom);
    return lResult;
}

function translateMatrix(m, x, y, z) {
    m = [...m];
    m[12] += x;
    m[13] += y;
    m[14] += z;
    return m;
}

function rotateMatrix2d(m, angle) {
    m = [...m];
    m[0] = Math.cos(angle);
    m[1] = -Math.sin(angle);
    m[4] = Math.sin(angle);
    m[5] = Math.cos(angle);
    return m;
}

function scaleMatrix(m, x, y, z) {
    m = [...m];
    m[0] = m[0] * x;
    m[5] = m[5] * y;
    m[10] = m[10] * z;
    return m;
}