# drawhelper-with-cesium-v1.41

**Repository Path**: ticpas/drawhelper-with-cesium-v1.41

## Basic Information

- **Project Name**: drawhelper-with-cesium-v1.41
- **Description**: No description available
- **Primary Language**: Unknown
- **License**: Apache-2.0
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 0
- **Created**: 2021-01-12
- **Last Updated**: 2021-01-12

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

1、在原<a href="https://github.com/leforthomas/cesium-drawhelper" target="_blank">cesium-drawhelper</a>基础上，修改了DrawHelper.js部分地方，从而能够支持最新的cesium v1.41，具体修改说明如下：
<br/>
2、294行
<br/>
	lineWidth: Math.min(this.strokeWidth || 4.0, context._aliasedLineWidthRange[1])
	<br/>
改为:
<br/>
	lineWidth: 1.0
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3、977行开始
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<pre>  
	function updateExtent(value) {
        if (extent == null) {
            extent = new Cesium.RectanglePrimitive();
            extent.asynchronous = false;
            primitives.add(extent);
        }
        extent.rectangle = value;
        // update the markers
        var corners = getExtentCorners(value);
        // create if they do not yet exist
        if (markers == null) {
            markers = new _.BillboardGroup(_self, defaultBillboard);
            markers.addBillboards(corners);
        } else {
            markers.updateBillboardsPositions(corners);
        }
    }

    // Now wait for start
    mouseHandler.setInputAction(function (movement) {
        if (movement.position != null) {
            var cartesian = scene.camera.pickEllipsoid(movement.position, ellipsoid);
            if (cartesian) {
                if (extent == null) {
                    // create the rectangle
                    firstPoint = ellipsoid.cartesianToCartographic(cartesian);
                    var value = getExtent(firstPoint, firstPoint);
                    updateExtent(value);
                } else {
                    _self.stopDrawing();
                    if (typeof options.callback == 'function') {
                        options.callback(getExtent(firstPoint, ellipsoid.cartesianToCartographic(cartesian)));
                    }
                }
            }
        }
    }, Cesium.ScreenSpaceEventType.LEFT_DOWN);

    mouseHandler.setInputAction(function (movement) {
        var position = movement.endPosition;
        if (position != null) {
            if (extent == null) {
                tooltip.showAt(position, "<p>Click to start drawing rectangle</p>");
            } else {
                var cartesian = scene.camera.pickEllipsoid(position, ellipsoid);
                if (cartesian) {
                    var value = getExtent(firstPoint, ellipsoid.cartesianToCartographic(cartesian));
                    updateExtent(value);
                    tooltip.showAt(position, "<p>Drag to change rectangle extent</p><p>Click again to finish drawing</p>");
                }
            }
        }
    }, Cesium.ScreenSpaceEventType.MOUSE_MOVE);
  }
</pre>
<br/>
替换为：
<br/>
<pre>  
    // Now wait for start
    mouseHandler.setInputAction(function (movement) {
        if (movement.position != null) {
            var cartesian = scene.camera.pickEllipsoid(movement.position, ellipsoid);
            if (cartesian) {
                if (extent == null) {
                    // create the rectangle
                    firstPoint = ellipsoid.cartesianToCartographic(cartesian);
                    var value = getExtent(firstPoint, firstPoint);
                    extent = new _.ExtentPrimitive({
                        extent: value,
                        asynchronous: false,
                        material: options.material
                    });
                    primitives.add(extent);
                    markers = new _.BillboardGroup(_self, defaultBillboard);
		    var corners = getExtentCorners(value);
                    markers.addBillboards(corners);
                } else {
                    _self.stopDrawing();
                    if (typeof options.callback == 'function') {
                        options.callback(getExtent(firstPoint, ellipsoid.cartesianToCartographic(cartesian)));
                    }
                }
            }
        }
    }, Cesium.ScreenSpaceEventType.LEFT_DOWN);

    mouseHandler.setInputAction(function (movement) {
        var position = movement.endPosition;
        if (position != null) {
            if (extent == null) {
                tooltip.showAt(position, "<p>Click to start drawing rectangle</p>");
            } else {
                var cartesian = scene.camera.pickEllipsoid(position, ellipsoid);
                if (cartesian) {
                    var value = getExtent(firstPoint, ellipsoid.cartesianToCartographic(cartesian));
                    extent.setExtent(value);
		    var corners = getExtentCorners(value);
                    markers.updateBillboardsPositions(corners);
                    tooltip.showAt(position, "<p>Drag to change rectangle extent</p><p>Click again to finish drawing</p>");
                }
            }
        }
    }, Cesium.ScreenSpaceEventType.MOUSE_MOVE);
}
</pre>