What I am looking for
Display a grid within a three.js scene that fills the entire scene. In this case, the scene is the whole window.
This grid represents a surface in 3D and can be moved around with the mouse using THREE.TrackballControls
This grid is facing the camera so initially it looks like a flat (2D) surface until the trackball is pulled around with the mouse.
The width of the grid lines should equal to the width of the renderer.
What I did
I have setup a working jsFiddle for what I have done so far.
First I find the bounds of the scene (all of this is in the jsFiddle),
App = function(sceneContainerName) {
this.sceneContainerName = sceneContainerName;
this.SCREEN_WIDTH = window.innerWidth;
this.SCREEN_HEIGHT = window.innerHeight;
this.MAX_X = this.SCREEN_WIDTH / 2;
this.MIN_X = 0 - (this.SCREEN_WIDTH / 2);
this.MAX_Y = this.SCREEN_HEIGHT / 2;
this.MIN_Y = 0 - (this.SCREEN_HEIGHT / 2);
this.NUM_HORIZONTAL_LINES = 50;
this.init();
};
Setup three.js
init: function() {
// init scene
this.scene = new THREE.Scene();
// init camera
// View Angle, Aspect, Near, Far
this.camera = new THREE.PerspectiveCamera(45, this.SCREEN_WIDTH / this.SCREEN_HEIGHT, 1, 10000);
// set camera position
this.camera.position.z = 1000;
this.camera.position.y = 0;
// add the camera to the scene
this.scene.add(this.camera);
this.projector = new THREE.Projector();
// init renderer
this.renderer = new THREE.CanvasRenderer();
// start the renderer
this.renderer.setSize(this.SCREEN_WIDTH, this.SCREEN_HEIGHT);
this.drawGrid(this.NUM_HORIZONTAL_LINES);
this.trackball = new THREE.TrackballControls(this.camera, this.renderer.domElement);
this.trackball.staticMoving = true;
var me = this;
this.trackball.addEventListener('change', function() {
me.render();
});
// attach the render-supplied DOM element
var container = document.getElementById(this.sceneContainerName);
container.appendChild(this.renderer.domElement);
this.animate();
},
These functions provide a vector for each screen corner,
getNWScreenVector: function() {
return new THREE.Vector3(this.MIN_X, this.MAX_Y, 0);
},
getNEScreenVector: function() {
return new THREE.Vector3(this.MAX_X, this.MAX_Y, 0);
},
getSWScreenVector: function() {
return new THREE.Vector3(this.MIN_X, this.MIN_Y, 0);
},
getSEScreenVector: function() {
return new THREE.Vector3(this.MAX_X, this.MIN_Y, 0);
},
I create some geometry that will represent a line at the very top of the screen, and try to draw lines starting from the top and going down to the bottom of the screen.
// drawGrid will determine blocksize based on the
// amount of horizontal gridlines to draw
drawGrid: function(numHorizontalGridLines) {
// Determine the size of a grid block (square)
this.gridBlockSize = this.SCREEN_HEIGHT / numHorizontalGridLines;
var geometry = new THREE.Geometry();
geometry.vertices.push(this.getNWScreenVector());
geometry.vertices.push(this.getNEScreenVector());
var material = new THREE.LineBasicMaterial({
color: 0x000000,
opacity: 0.2
});
for (var c = 0; c <= numHorizontalGridLines; c++) {
var line = new THREE.Line(geometry, material);
line.position.y = this.MAX_Y - (c * this.gridBlockSize);
this.scene.add(line);
}
}
The problem
This method does not work, in the jsFiddle the first line starts off the screen and the width of the lines do not fill the screen width.