143 lines
3.1 KiB
JavaScript
143 lines
3.1 KiB
JavaScript
GameLib.D3.Vector3 = function(x, y, z) {
|
|
|
|
this.x = 0;
|
|
this.y = 0;
|
|
this.z = 0;
|
|
|
|
if (x) {
|
|
this.x = x;
|
|
}
|
|
|
|
if (y) {
|
|
this.y = y;
|
|
}
|
|
|
|
if (z) {
|
|
this.z = z;
|
|
}
|
|
};
|
|
|
|
GameLib.D3.Vector3.prototype.subtract = function (v) {
|
|
|
|
if (v instanceof GameLib.D3.Vector3) {
|
|
this.x -= v.x;
|
|
this.y -= v.y;
|
|
this.z -= v.z;
|
|
}
|
|
|
|
if (v instanceof GameLib.D3.Vector4) {
|
|
console.warn("trying to subtract vector of bigger length (4 vs 3))");
|
|
}
|
|
|
|
return this;
|
|
};
|
|
|
|
GameLib.D3.Vector3.prototype.cross = function (v) {
|
|
return new GameLib.D3.Vector3(
|
|
this.y * v.z - this.z * v.y,
|
|
this.z * v.x - this.x * v.z,
|
|
this.x * v.y - this.y * v.x
|
|
);
|
|
};
|
|
|
|
GameLib.D3.Vector3.prototype.negative = function () {
|
|
this.x *= -1;
|
|
this.y *= -1;
|
|
this.z *= -1;
|
|
return this;
|
|
};
|
|
|
|
GameLib.D3.Vector3.clockwise = function (u, v, w, viewPoint) {
|
|
|
|
var normal = GameLib.D3.Vector3.normal(u, v, w);
|
|
|
|
var uv = u.copy();
|
|
|
|
var winding = normal.dot(uv.subtract(viewPoint));
|
|
|
|
return (winding > 0);
|
|
};
|
|
|
|
GameLib.D3.Vector3.normal = function (u, v, w) {
|
|
var vv = v.copy();
|
|
var wv = w.copy();
|
|
return vv.subtract(u).cross(wv.subtract(u));
|
|
};
|
|
|
|
GameLib.D3.Vector3.prototype.lookAt = function (at, up) {
|
|
|
|
var lookAtMatrix = GameLib.D3.Matrix4.lookAt(this, at, up);
|
|
|
|
this.multiply(lookAtMatrix);
|
|
};
|
|
|
|
GameLib.D3.Vector3.prototype.translate = function (v) {
|
|
this.x += v.x;
|
|
this.y += v.y;
|
|
this.z += v.z;
|
|
return this;
|
|
};
|
|
|
|
GameLib.D3.Vector3.prototype.squared = function () {
|
|
return this.x * this.x + this.y * this.y + this.z * this.z;
|
|
};
|
|
|
|
GameLib.D3.Vector3.prototype.copy = function () {
|
|
return new GameLib.D3.Vector3(
|
|
this.x,
|
|
this.y,
|
|
this.z
|
|
);
|
|
};
|
|
|
|
GameLib.D3.Vector3.prototype.lerp = function ( v, alpha ) {
|
|
return new GameLib.D3.Vector3(
|
|
this.x + ( v.x - this.x ) * alpha,
|
|
this.y + ( v.y - this.y ) * alpha,
|
|
this.z + ( v.z - this.z ) * alpha
|
|
);
|
|
};
|
|
|
|
GameLib.D3.Vector3.prototype.multiply = function (s) {
|
|
if (s instanceof GameLib.D3.Vector3) {
|
|
this.x *= s.x;
|
|
this.y *= s.y;
|
|
this.z *= s.z;
|
|
} else if (s instanceof GameLib.D3.Matrix4) {
|
|
var x = s.rows[0].x * this.x + s.rows[0].y * this.y + s.rows[0].z * this.z;
|
|
var y = s.rows[1].x * this.x + s.rows[1].y * this.y + s.rows[1].z * this.z;
|
|
var z = s.rows[2].x * this.x + s.rows[2].y * this.y + s.rows[2].z * this.z;
|
|
this.x = x;
|
|
this.y = y;
|
|
this.z = z;
|
|
} else {
|
|
console.log("functionality not implemented - please do this");
|
|
throw new Error("not implemented");
|
|
}
|
|
return this;
|
|
};
|
|
|
|
|
|
GameLib.D3.Vector3.prototype.dot = function (v) {
|
|
return (this.x * v.x) + (this.y * v.y) + (this.z * v.z);
|
|
};
|
|
|
|
GameLib.D3.Vector3.prototype.normalize = function () {
|
|
|
|
var EPSILON = 0.000001;
|
|
|
|
var v2 = this.squared();
|
|
|
|
if (v2 < EPSILON) {
|
|
return this; //do nothing for zero vector
|
|
}
|
|
|
|
var invLength = 1 / Math.sqrt(v2);
|
|
|
|
this.x *= invLength;
|
|
this.y *= invLength;
|
|
this.z *= invLength;
|
|
|
|
return this;
|
|
};
|