useSceneDrillPick
响应式封装 Cesium.Scene.drillPick:根据屏幕坐标穿透拾取重叠的全部对象,返回结果数组的响应式引用。适用于重叠图形需要“先拾取、再从列表选择目标”的场景;与仅取最上层的 useScenePick 互补。
Usage
vue
<script setup lang="ts">
import * as Cesium from 'cesium';
import { useEntity, useSceneDrillPick, useScreenSpaceEventHandler, useViewer } from 'vesium';
import { computed, shallowRef, watchEffect } from 'vue';
const cursorPosition = shallowRef<Cesium.Cartesian2>();
// track mouse move
useScreenSpaceEventHandler(Cesium.ScreenSpaceEventType.MOUSE_MOVE, (movement: { endPosition: Cesium.Cartesian2 }) => {
cursorPosition.value = movement.endPosition.clone();
});
// use scene drill pick to pick multiple objects at cursor
const drillPick = useSceneDrillPick(cursorPosition, {
width: 5,
height: 5,
limit: 10,
});
// show all picked objects
const pickInfo = computed(() => {
if (!drillPick.value || drillPick.value.length === 0) {
return 'No object picked';
}
const names = drillPick.value.map((item: any, index: number) => {
if (item.id instanceof Cesium.Entity) {
return `${index + 1}. Entity: ${item.id.name || 'unnamed'}`;
}
if (item.primitive) {
return `${index + 1}. Primitive: ${item.primitive.id?.name || 'unnamed'}`;
}
return `${index + 1}. Unknown`;
});
return names.join('\n');
});
// three boxes stacked at the same ground position — hover the center to drill all layers
const entities = useEntity([
new Cesium.Entity({
name: 'Layer 1 - Red',
position: Cesium.Cartesian3.fromDegrees(120, 30, 500),
box: {
dimensions: new Cesium.Cartesian3(4000, 4000, 1000),
material: new Cesium.ColorMaterialProperty(Cesium.Color.RED.withAlpha(0.6)),
},
}),
new Cesium.Entity({
name: 'Layer 2 - Green',
position: Cesium.Cartesian3.fromDegrees(120, 30, 1200),
box: {
dimensions: new Cesium.Cartesian3(2600, 2600, 800),
material: new Cesium.ColorMaterialProperty(Cesium.Color.GREEN.withAlpha(0.6)),
},
}),
new Cesium.Entity({
name: 'Layer 3 - Blue',
position: Cesium.Cartesian3.fromDegrees(120, 30, 1800),
box: {
dimensions: new Cesium.Cartesian3(1400, 1400, 600),
material: new Cesium.ColorMaterialProperty(Cesium.Color.BLUE.withAlpha(0.6)),
},
}),
]);
const viewer = useViewer();
watchEffect(() => {
if (viewer.value && entities.value) {
viewer.value.flyTo(entities.value, { duration: 1 });
}
});
</script>
<template>
<div class="text-12px p-10px whitespace-pre-wrap">
{{ pickInfo }}
</div>
</template>ts
import * as Cesium from 'cesium';
import { useSceneDrillPick, useScreenSpaceEventHandler } from 'vesium';
import { shallowRef } from 'vue';
const cursorPosition = shallowRef<Cesium.Cartesian2>();
useScreenSpaceEventHandler(Cesium.ScreenSpaceEventType.MOUSE_MOVE, (m) => {
cursorPosition.value = m.endPosition.clone();
});
const picks = useSceneDrillPick(cursorPosition, { limit: 10 }); // 最多 10 个,可降低开销
picks.value?.forEach((item, index) => {
console.log(`${index + 1}.`, item.id.name);
});配置项
isActive- 是否激活拾取,默认true;为false时结果重置为undefined,支持 ref/getter。throttled- 坐标变化的节流采样间隔(毫秒),默认8。limit- 最多收集的结果数量,透传给scene.drillPick;不传返回全部命中对象,传较小值可降低开销。width/height- 拾取矩形宽高,默认3。
返回值
- 返回
ComputedRef<any[] | undefined>:拾取结果数组,元素含id、primitive等字段(对应scene.drillPick返回项);无命中或条件不满足时为undefined。
注意事项
drillPick单次开销大于pick,请配合throttled节流和limit限制数量。- viewer 不存在、位置为空或
isActive为false时,结果重置为undefined。
Type Definitions
typescript
import type { Cartesian2 } from 'cesium';
import type { ComputedRef, MaybeRefOrGetter } from 'vue';
export interface UseSceneDrillPickOptions {
/**
* Whether to activate the pick function.
* @default true
*/
isActive?: MaybeRefOrGetter<boolean | undefined>;
/**
* Throttled sampling (ms)
* @default 8
*/
throttled?: number;
/**
* If supplied, stop drilling after collecting this many picks.
*/
limit?: MaybeRefOrGetter<number | undefined>;
/**
* The width of the pick rectangle.
* @default 3
*/
width?: MaybeRefOrGetter<number | undefined>;
/**
* The height of the pick rectangle.
* @default 3
*/
height?: MaybeRefOrGetter<number | undefined>;
}
/**
* Uses the `scene.drillPick` function to perform screen point picking,
* return a computed property containing the pick result, or undefined if no object is picked.
*
* @param windowPosition The screen coordinates of the pick point.
*/
export declare function useSceneDrillPick(windowPosition: MaybeRefOrGetter<Cartesian2 | undefined>, options?: UseSceneDrillPickOptions): ComputedRef<any[] | undefined>;