From 9a56e6923fb1b0f67e98816a117de0d21c583410 Mon Sep 17 00:00:00 2001
From: Arnold <40414978+PatriceJiang@users.noreply.github.com>
Date: Wed, 3 Apr 2019 17:27:15 +0800
Subject: [PATCH] [bugfix] motionstreak & DrawNode3D on GL (#19564)

---
 cocos/2d/CCMotionStreak.cpp                     |  9 ++++++++-
 cocos/renderer/backend/opengl/BufferGL.cpp      | 17 +++++------------
 cocos/renderer/backend/opengl/BufferGL.h        |  2 +-
 .../Classes/Sprite3DTest/DrawNode3D.cpp         | 13 +++++++++++--
 4 files changed, 25 insertions(+), 16 deletions(-)

diff --git a/cocos/2d/CCMotionStreak.cpp b/cocos/2d/CCMotionStreak.cpp
index 3fec359f50..3f6074cfa3 100644
--- a/cocos/2d/CCMotionStreak.cpp
+++ b/cocos/2d/CCMotionStreak.cpp
@@ -133,11 +133,18 @@ bool MotionStreak::initWithFade(float fade, float minSeg, float stroke, const Co
     _pointState = (float *)malloc(sizeof(float) * _maxPoints);
     _pointVertexes = (Vec2*)malloc(sizeof(Vec2) * _maxPoints);
 
+    const size_t VERTEX_SIZE = sizeof(Vec2) + sizeof(Tex2F) + sizeof(uint8_t) * 4;
+
     _vertexCount = _maxPoints * 2;
     _vertices = (Vec2*)malloc(sizeof(Vec2) * _vertexCount);
     _texCoords = (Tex2F*)malloc(sizeof(Tex2F) * _vertexCount);
     _colorPointer =  (uint8_t*)malloc(sizeof(uint8_t) * 4 * _vertexCount);
-    _customCommand.createVertexBuffer(sizeof(Vec2) + sizeof(Tex2F) + sizeof(uint8_t) * 4, _vertexCount, CustomCommand::BufferUsage::DYNAMIC);
+    _customCommand.createVertexBuffer(VERTEX_SIZE, _vertexCount, CustomCommand::BufferUsage::DYNAMIC);
+
+    std::vector<uint8_t> zeros;
+    zeros.resize(VERTEX_SIZE * _vertexCount);
+    std::fill(zeros.begin(), zeros.end(), 0);
+    _customCommand.updateVertexBuffer(zeros.data(), zeros.size());
 
     setTexture(texture);
     setColor(color);
diff --git a/cocos/renderer/backend/opengl/BufferGL.cpp b/cocos/renderer/backend/opengl/BufferGL.cpp
index d559474a45..d2faf13b6f 100644
--- a/cocos/renderer/backend/opengl/BufferGL.cpp
+++ b/cocos/renderer/backend/opengl/BufferGL.cpp
@@ -17,7 +17,7 @@ BufferGL::~BufferGL()
 
 void BufferGL::updateData(void* data, unsigned int size)
 {
-    assert(size);
+    assert(size && size <= _size);
     
     if (_buffer)
     {
@@ -32,22 +32,16 @@ void BufferGL::updateData(void* data, unsigned int size)
             glBufferData(GL_ELEMENT_ARRAY_BUFFER, size, data, GL_STATIC_DRAW);
         }
         CHECK_GL_ERROR_DEBUG();
-        _bufferAllocated = true;
+        _bufferAllocated = size;
     }
 }
 
 void BufferGL::updateSubData(void* data, unsigned int offset, unsigned int size)
 {
-    assert(offset + size <= _size);
-    
-    //invoke updateData if buffer is not allocated
-    if (!_bufferAllocated)
-    {
-        CCASSERT(offset == 0, "offset should be zero when allocate buffer");
-        updateData(data, size);
-        return;
-    }
 
+    CCASSERT(_bufferAllocated != 0, "updateData should be invoke before updateSubData");
+    CCASSERT(offset + size <= _bufferAllocated, "buffer size overflow");
+ 
     if (_buffer)
     {
         CHECK_GL_ERROR_DEBUG();
@@ -55,7 +49,6 @@ void BufferGL::updateSubData(void* data, unsigned int offset, unsigned int size)
         {
             glBindBuffer(GL_ARRAY_BUFFER, _buffer);
             glBufferSubData(GL_ARRAY_BUFFER, offset, size, data);
-            
         }
         else
         {
diff --git a/cocos/renderer/backend/opengl/BufferGL.h b/cocos/renderer/backend/opengl/BufferGL.h
index 0c0748b7ae..c99e22e907 100644
--- a/cocos/renderer/backend/opengl/BufferGL.h
+++ b/cocos/renderer/backend/opengl/BufferGL.h
@@ -19,7 +19,7 @@ public:
     
 private:
     GLuint _buffer = 0;
-    bool _bufferAllocated = false;
+    unsigned int _bufferAllocated = 0;
 };
 
 CC_BACKEND_END
diff --git a/tests/cpp-tests/Classes/Sprite3DTest/DrawNode3D.cpp b/tests/cpp-tests/Classes/Sprite3DTest/DrawNode3D.cpp
index 4fd2b885e5..3991b239fe 100644
--- a/tests/cpp-tests/Classes/Sprite3DTest/DrawNode3D.cpp
+++ b/tests/cpp-tests/Classes/Sprite3DTest/DrawNode3D.cpp
@@ -24,7 +24,7 @@
  ****************************************************************************/
 
 #include "DrawNode3D.h"
-
+#include "renderer/backend/Buffer.h"
 NS_CC_BEGIN
 
 
@@ -58,7 +58,15 @@ void DrawNode3D::ensureCapacity(int count)
 {
     CCASSERT(count>=0, "capacity must be >= 0");
     
-    _bufferLines.reserve(_bufferLines.size() + count);
+    const int EXTENDED_SIZE = _bufferLines.size() + count;
+
+    _bufferLines.reserve(EXTENDED_SIZE);
+
+    if (!_customCommand.getVertexBuffer() || _customCommand.getVertexBuffer()->getSize() < (EXTENDED_SIZE * sizeof(_bufferLines[0])))
+    {
+        _customCommand.createVertexBuffer(sizeof(V3F_C4B), EXTENDED_SIZE + (EXTENDED_SIZE >> 1), CustomCommand::BufferUsage::DYNAMIC);
+    }
+
 }
 
 bool DrawNode3D::init()
@@ -120,6 +128,7 @@ void DrawNode3D::draw(Renderer *renderer, const Mat4 &transform, uint32_t flags)
     if (_isDirty && !_bufferLines.empty())
     {
         _customCommand.updateVertexBuffer(_bufferLines.data(), (unsigned int)(_bufferLines.size() * sizeof(_bufferLines[0])));
+        _customCommand.setVertexDrawInfo(0, _bufferLines.size());
         _isDirty = false;
     }