I am trying to rotate billboard text. I want the text to be rotated at the origin point I set with verticalOrigin and horizontalOrigin. When I apply a rotation, the rotation is based on the image center, not the origin point I specified.
How do I rotate the billboard at the origin point instead?
map.entities.add({
position : Cesium.Cartesian3.from Degrees(),
billboard : {
image : Cesium.writeTextToCanvas('ANCHOR POINT', {
font : '12pt Arial, sans-serif',
fillColor : Cesium.Color.AQUA
}),
rotation : Cesium.Math.toRadians(0),
alignedAxis : Cesium.Cartesian3.UNIT_Z,
verticalOrigin : Cesium.VerticalOrigin.CENTER,
horizontalOrigin : Cesium.HorizontalOrigin.LEFT
}
})
OP ended up filing an issue and asking a community question about this on the Cesium forums.
The answer is that there isn't a direct way to set the rotation to happen around another point, even though it makes intuitive sense that verticalOrigin and horizontalOrigin should control this. See the source of vert_shader for details.
As a workaround, you can accomplish the same thing by applying the rotation to the center, and then shifting the position of the billboard (using trig to calculate the offsets) so it is placed as if the rotation happened at the edge. The calculated offsets can be passed as an additional property on the billboard:
map.entities.add({
position : Cesium.Cartesian3.from Degrees(),
billboard : {
image : Cesium.writeTextToCanvas('ANCHOR POINT', {
font : '12pt Arial, sans-serif',
fillColor : Cesium.Color.AQUA
}),
rotation : Cesium.Math.toRadians(0),
alignedAxis : Cesium.Cartesian3.UNIT_Z,
position : new Cesium.Cartesian3(x_offset, y_offset, z_offset)
}
})
I've opened a feature request on GitHub to fix this.
Related
I've generated a generated a GLB file using khronos's SharpGLTF libraries and have got the model loading in cesium, the model appears correctly. The problem is the material for the model does not show. I have tested the generated GLB in other viewers and the material does show.
I'm using the following code in cesium:
var entity = viewer.entities.add({
name : 'url_here',
position : center,
orientation : orientation,
model : {
uri : 'url_here',
minimumPixelSize : 128,
maximumScale : 20000,
}
});
also tried
var model = scene.primitives.add(Cesium.Model.fromGltf({
id: 'here',
url: 'url here'
modelMatrix : modelMatrix,
scale : 1.0,
}));
I've tried using the color modifiers for cesium and the only option that responds is "color" which doesn't help as it doesn't apply any lighting to the color.
Below is a picture of what cesium is outputting. However there should be more effects to the material than just red. It seems to respect only KnownChannel.BaseColor and that's it.
Any ideas?
I am trying to create a special material for a Cesium Polygon, which has to incorporate a hatched area with an outline.
Now, from the base materials I can use "Stripe", so i can create my graphic like this:
var viewer = new Cesium.Viewer('cesiumContainer');
var degrees_array = [
92.1470732697006,
21.954465553476467,
99.08781126987297,
32.557089696031916,
68.66765785924682,
24.272023818381587
];
var polygon = viewer.entities.add({
name : 'polygon',
polygon : {
hierarchy : Cesium.Cartesian3.fromDegreesArray(degrees_array),
extrudedHeight: 0,
material : new Cesium.StripeMaterialProperty(
{
evenColor:Cesium.Color.GRAY,
oddColor:Cesium.Color.WHITE,
orientation: Cesium.StripeOrientation.HORIZONTAL,
repeat:100,
offset:0
}
),
//outline is ignored by WebGL
//outline: true,
//outlineColor:Cesium.Color.BLACK,
//outlineWidth:1
}
});
//since designing an outline is not possible with polygon we create a custom polylineGraphics:
var outline_array = degrees_array;
// since loop is not available for polylineGraphics we add the first point positions
outline_array.push(outline_array[0],outline_array[1]);
var outline = viewer.entities.add({
polyline : {
positions : Cesium.Cartesian3.fromDegreesArray(outline_array),
width : 5,
material : Cesium.Color.GRAY,
clampToGround:true,
zIndex:0
}
});
viewer.zoomTo(polygon)
see sandcastle link
My questions:
- is there a way to rotate the stripes, so that they appear as diagonally hatched
- can zoom be omitted for the Stripe material, so that it is always displayed with the same line width?
Thanks a lot!
If you are still wondering. You can rotate the stripes by using stRotation
polygon: {
hierarchy: <posititons>
stRotation: Cesium.Math.toRadians(45),
material: stripeMaterial,
}
I think I mean "translucent"...
I'm trying to put a rectangle with an image material and control the translucency of the image so I can see the background behind it (like we do with ordinary layers).
This is my code:
var redRectangle = viewer.entities.add({
name : 'Red translucent rectangle',
rectangle : {
coordinates : Cesium.Rectangle.fromDegrees(-110.0, 20.0, -80.0, 25.0),
material : new Cesium.ImageMaterialProperty({
image : '../images/Cesium_Logo_Color.jpg',
transparent: true,
translucent : true,
alpha: 0.2
}),
}
});
I can't get it to work. I already tried every option inside material but with no results.
try it in Sandcastle. My goal is to see a translucid logo.
Solved.
Need to give a color to the image ( what?? ) and apply an alpha to it.
var redRectangle = viewer.entities.add({
name : 'Red translucent rectangle',
rectangle : {
coordinates : Cesium.Rectangle.fromDegrees(-110.0, 20.0, -80.0, 25.0),
material : new Cesium.ImageMaterialProperty({
image : '../images/Cesium_Logo_Color.jpg',
color: Cesium.Color.WHITE.withAlpha(0.1) <<<< ----- THIS MAKE IT TRANSLUCENT
}),
}
});
I add the anntation like this
var annot= Map.createAnnotation({
latitude: XXXXXXXXXXX,
longitude: XXXXXXXXXX,
title: 'myPlace',
image: 'myPin.png',
width:'100dp',// doesn't work
height:'100dp'// doesn't work
});
this.mapView.addAnnotation(annot);
}
I would like to change the size of image though,
there seems no way to change.
So I need to edit the file size itself by image editor or something.
Moreover images are show differently in Android or iPhone.
So I need to make two size for each pins.
MapModule.createAnnotation({
latitude : XXXX,
longitude : XXXX,
customView : Ti.UI.createView({
width : widthImg,
height : heightImg * 2,
children : [Ti.UI.createView({
top : 0,
width : width,
height : height,
backgroundImage : "myPin.png"
})]
})
});
I have this code, which adds polyline primitive to scene.
function createPolyline(startPosition, endPosition) {
Cesium.SimplePolylineGeometry({
positions : [startPosition, endPosition]
});
var geometry = Cesium.SimplePolylineGeometry.createGeometry(polyline);
return scene.primitives.add(new Cesium.Primitive({
geometryInstances : new Cesium.GeometryInstance({
geometry : geometry,
attributes : {
color : Cesium.ColorGeometryInstanceAttribute.fromColor(Cesium.Color.SPRINGGREEN)
}
}),
appearance : new Cesium.PerInstanceColorAppearance()
}));
}
How do I set width of this polyline?
The recommended way to add a polyline is with the Entity API, like this
var greenLine = viewer.entities.add({
polyline : {
positions : [startPosition, endPosition],
width : 5,
material : Cesium.Color.SPRINGGREEN
}
});
But, if you want to skip the Entity layer and use the Primitive Graphics layer directly, you can do that too. Your sample code above has some issues. First, you're calling the Cesium.SimplePolylineGeometry constructor without the new keyword, and without saving the result, and this is not the correct use pattern for this kind of code. Second, the SimplePolylineGeometry class itself does not support line widths greater than what the WebGL implementation supports, which on Windows machines running ANGLE, is only 1 pixel wide. To get around this limitation, use the normal (non-simple) polylines, like this:
var polylines = scene.primitives.add(new Cesium.PolylineCollection());
var polyline = polylines.add({
positions : Cesium.PolylinePipeline.generateCartesianArc({
positions : [startPosition, endPosition]
}),
material : Cesium.Material.fromType('Color', {
color : Cesium.Color.SPRINGGREEN
}),
width: 5
});
SimplePolylineGeometry does not support line width. You need to use PolylineGeometry instead and pass the "width" options to the constructor. Also, you should be using PolylineColorAppearance as your appearance, not PerInstanceColorAppearance.