feat: 缓动函数加法与乘法

src/core/render/utils.ts

@@ -1,3 +1,4 @@
+import { TimingFn } from 'mutate-animate';
 import { RenderAdapter } from './adapter';
 import { FloorViewport } from './preset/viewport';
 
@@ -12,3 +13,17 @@ export function enableViewport() {
     if (!adapter) return;
     adapter.sync('disable');
 }
+
+/**
+ * 将两个缓动函数做加法
+ */
+export function AddTiming(timing1: TimingFn, timing2: TimingFn): TimingFn {
+    return (p: number) => timing1(p) + timing2(p);
+}
+
+/**
+ * 将两个缓动函数做乘法
+ */
+export function multiplyTiming(timing1: TimingFn, timing2: TimingFn): TimingFn {
+    return (p: number) => timing1(p) * timing2(p);
+}