module:extras/raypick
The extras/raypick.js module.
To import all symbols in this module, either of the following can be used:
import * from "extras/raypick.js"; // -- or -- import * as CustomModuleName from "extras/raypick.js";
Methods
- raypick
Finds the three-dimensional shape object and world-space coordinates corresponding to the given two-dimensional (X and Y) coordinates.
### (static) module:extras/raypick.raypick(x, y, projView, viewport, objects)
Finds the three-dimensional shape object and world-space coordinates corresponding to the given two-dimensional (X and Y) coordinates.
Parameters
x
Two-dimensional X coordinate in window space (usually lying within the viewport rectangle). See also the first parameter of MathUtil.vec3fromWindowPoint.y
Two-dimensional Y coordinate in window space (usually lying within the viewport rectangle). See also the first parameter of MathUtil.vec3fromWindowPoint.projView
Same meaning as second parameter of MathUtil.vec3fromWindowPoint. For example, to convert to world space coordinates, pass a projection matrix (projection matrix multiplied by the view matrix, in that order) to this parameter.viewport
Same meaning as third parameter of MathUtil.vec3fromWindowPoint.objects
Shape objects from which this method will choose one.
Return Value
An object with the following properties:<ul>
index - Index, starting from 0, into the objects array
of the shape object that was picked. Is -1 if no object was picked
(and the "local" and "world" properties will be absent).
local - 3-element array giving the X, Y, and
Z coordinates of the picked point in object (model) space.
world - 3-element array giving the X, Y, and
Z coordinates of the picked point in world space.</ul>
#### Examples
The following example shows how a hypothetical scene graph could implement picking objects based on the position of the mouse cursor.
var mousePos = scene.getMousePosInPixels();
var viewport = [0, 0, scene.getWidth(), scene.getHeight()];
var projview = scene.getProjectionViewMatrix();
var o = raypick(mousePos.cx, mousePos.cy, projview, viewport, objects);
if(o.index >= 0) {
pickedShape = objects[o.index];
} else {
pickedShape = null;
}
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