From acdcd87d00b5464fafd5a236532878c5980eda97 Mon Sep 17 00:00:00 2001
From: minggo <nudtzxm@gmail.com>
Date: Thu, 3 Sep 2020 20:03:26 +0800
Subject: [PATCH] invoke function to set blend target (#7299)

---
 cocos/core/gfx/pipeline-state.ts | 14 +++++++++++++-
 cocos/core/renderer/core/pass.ts |  2 +-
 2 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/cocos/core/gfx/pipeline-state.ts b/cocos/core/gfx/pipeline-state.ts
index fb7adb575ed..856829c6d03 100644
--- a/cocos/core/gfx/pipeline-state.ts
+++ b/cocos/core/gfx/pipeline-state.ts
@@ -138,7 +138,19 @@ export class GFXBlendState {
     public isA2C: boolean = false;
     public isIndepend: boolean = false;
     public blendColor: GFXColor = { r: 0, g: 0, b: 0, a: 0 };
-    public targets: GFXBlendTarget[] = [new GFXBlendTarget()];
+    public targets: GFXBlendTarget[] = [new GFXBlendTarget()]
+
+    /**
+     * @en Should use this function to set target, or it will not work
+     * on native platforms, as native can not support this feature, 
+     * such as `blendState[i] = target;`.
+     * 
+     * @param index The index to set target.
+     * @param target The target to be set.
+     */
+    public setTarget (index: number, target: GFXBlendTarget) {
+        this.targets[index] = target;
+    }
 }
 
 /**
diff --git a/cocos/core/renderer/core/pass.ts b/cocos/core/renderer/core/pass.ts
index 5f41ba23735..c4d0ac60bd7 100644
--- a/cocos/core/renderer/core/pass.ts
+++ b/cocos/core/renderer/core/pass.ts
@@ -140,7 +140,7 @@ export class Pass {
             const bsInfo = info.blendState;
             if (bsInfo.targets) {
                 bsInfo.targets.forEach((t, i) => Object.assign(
-                bs.targets[i] || (bs.targets[i] = new GFXBlendTarget()), t));
+                bs.targets[i] || (bs.setTarget(i, new GFXBlendTarget()), t)));
             }
             if (bsInfo.isA2C !== undefined) { bs.isA2C = bsInfo.isA2C; }
             if (bsInfo.isIndepend !== undefined) { bs.isIndepend = bsInfo.isIndepend; }