Good Day all,
I've been working with Cesium for a bit now and I started when Primitive Collections were the thing to use. I had click and drag primitive rendering working, but now I want to upgrade Cesium and move on to entities. I moved over the code, refactored, and can click and drag to draw shapes; however, before I was able to flip the asynchronous flag and it would render as I moved the mouse. Now, I'm unable to do that. I tried setting 'allowDataSourcesToSuspendAnimation' on the viewer to false, but to no avail. Any help would be extremely appreciated.
In my naivety I forgot to add a code snippet to my question. This is in a clock tick event listener that only fires when mouse down is happening(Boolean value set to true)
var radius = Cesium.Cartesian3.distance(cartesianStartMousePosition, cartesianMousePosition);
if (radius > 0) {
if (currentEntity && currentEntity.id) {
currentEntity.position = cartesianStartMousePosition;
currentEntity.ellipse = {
semiMinorAxis: radius,
semiMajorAxis: radius,
material: new Cesium.ColorMaterialProperty(myColor)
};
currentEntity.label = {
text: 'New Overlay',
scale: 0.35
};
overlayEntities.resumeEvents();
}
else {
currentEntity = new Cesium.Entity({
position: cartesianStartMousePosition,
ellipse: {
semiMinorAxis: radius,
semiMajorAxis: radius,
material: new Cesium.ColorMaterialProperty(myColor)
},
label: {
text: 'New Overlay',
scale: 0.35
},
isSaved: false
});
overlayEntities.add(currentEntity);
}
bDrewPrim = true;
}
It looks to me like you're doing too much work to update the entity. You only need to set the values that have changed, and you should only do that if the change was substantial enough to warrant a graphics update. Try replacing the top half of your if statement with something like this:
var lastRadius = 0;
...
if (radius > 0 && !Cesium.Math.equalsEpsilon(radius, lastRadius, Cesium.Math.EPSILON2)) {
lastRadius = radius;
if (currentEntity && currentEntity.id) {
currentEntity.ellipse.semiMinorAxis = radius;
currentEntity.ellipse.semiMajorAxis = radius;
} else {
// Same as before...
I believe the ellipsoid primitive is being built on a worker thread, so this code tries to avoid setting the new radius every tick unless a real change has been applied to it.
Also, you don't show your mouse down handler, but make sure that you're setting this flag, if you aren't already setting it:
viewer.scene.screenSpaceCameraController.enableInputs = false;
This stops the globe from spinning while you drag-select the ellipse. You can reset this to true on mouse up.