【解决办法】参考代码如下：
var redWall = viewer.entities.add({
name: 'Red wall at height',
wall: {
positions: Cesium.Cartesian3.fromDegreesArrayHeights([
121.444409, 31.247417, 200.0,
121.533521, 31.235685, 200.0,
121.563273, 31.190347, 200.0,
121.546744, 31.194054, 200.0,
121.516705, 31.191459, 200.0,
121.502188, 31.203074, 200.0
]),
minimumHeights: [3000.0, 2000.0, 2000, 2000, 2000, 3000],
material: getColorRamp([0.0, 0.045, 0.1, 0.15, 0.37, 0.54, 1.0],true)
}
});
//纹理图绘制
function getColorRamp(elevationRamp) {
var ramp = document.createElement('canvas');
ramp.width = 1;
ramp.height = 100;
var ctx = ramp.getContext('2d');
var values = elevationRamp;
var grd = ctx.createLinearGradient(0, 0, 0, 100);
grd.addColorStop(values[0], '#000000'); //black
grd.addColorStop(values[1], '#2747E0'); //blue
grd.addColorStop(values[2], '#D33B7D'); //pink
grd.addColorStop(values[3], '#D33038'); //red
grd.addColorStop(values[4], '#FF9742'); //orange
grd.addColorStop(values[5], '#ffd700'); //yellow
grd.addColorStop(values[6], '#ffffff'); //white
ctx.fillStyle = grd;
ctx.fillRect(0, 0, 1, 100);
return ramp;
}
