add clear feature when before draw scene with a camera

build/cocos2d_libs.xcodeproj/project.pbxproj

@@ -3640,6 +3640,8 @@
 		B217704C1977ED8B009EE11B /* libsqlite3.dylib */ = {isa = PBXFileReference; lastKnownFileType = "compiled.mach-o.dylib"; name = libsqlite3.dylib; path = usr/lib/libsqlite3.dylib; sourceTree = SDKROOT; };
 		B230ED6F19B417AE00364AA8 /* CCTrianglesCommand.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; path = CCTrianglesCommand.cpp; sourceTree = "<group>"; };
 		B230ED7019B417AE00364AA8 /* CCTrianglesCommand.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = CCTrianglesCommand.h; sourceTree = "<group>"; };
+		B241A6E21AFB0BE700C5623C /* ccShader_CameraClear.frag */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.glsl; path = ccShader_CameraClear.frag; sourceTree = "<group>"; };
+		B241A6E31AFB0BE700C5623C /* ccShader_CameraClear.vert */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.glsl; path = ccShader_CameraClear.vert; sourceTree = "<group>"; };
 		B24AA981195A675C007B4522 /* CCFastTMXLayer.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; path = CCFastTMXLayer.cpp; sourceTree = "<group>"; };
 		B24AA982195A675C007B4522 /* CCFastTMXLayer.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = CCFastTMXLayer.h; sourceTree = "<group>"; };
 		B24AA983195A675C007B4522 /* CCFastTMXTiledMap.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; path = CCFastTMXTiledMap.cpp; sourceTree = "<group>"; };
@@ -5956,6 +5958,8 @@
 		5034CA5D191D591900CE6051 /* shaders */ = {
 			isa = PBXGroup;
 			children = (
+				B241A6E21AFB0BE700C5623C /* ccShader_CameraClear.frag */,
+				B241A6E31AFB0BE700C5623C /* ccShader_CameraClear.vert */,
 				B603F1B11AC8F1FD00A9579C /* ccShader_3D_Terrain.frag */,
 				B603F1B21AC8F1FD00A9579C /* ccShader_3D_Terrain.vert */,
 				B6D38B941AC3B45600043997 /* ccShader_3D_Particle.frag */,

cocos/2d/CCCamera.cpp

@@ -25,6 +25,9 @@
 #include "base/CCDirector.h"
 #include "platform/CCGLView.h"
 #include "2d/CCScene.h"
+#include "renderer/CCRenderer.h"
+#include "renderer/CCQuadCommand.h"
+#include "renderer/CCGLProgramCache.h"
 
 NS_CC_BEGIN
 
@@ -377,4 +380,59 @@ void Camera::setScene(Scene* scene)
     }
 }
 
+void Camera::onBeforeClear()
+{
+    glColorMask(GL_FALSE, GL_FALSE, GL_FALSE, GL_FALSE);
+    glStencilMask(0);
+    _oldDepthTest = glIsEnabled(GL_DEPTH_TEST);
+    glGetIntegerv(GL_DEPTH_FUNC, &_oldDepthFunc);
+    glEnable(GL_DEPTH_TEST);
+    glDepthFunc(GL_ALWAYS);
+}
+
+void Camera::onEndClear()
+{
+    if(GL_FALSE == _oldDepthTest)
+    {
+        glDisable(GL_DEPTH_TEST);
+    }
+    glDepthFunc(_oldDepthFunc);
+    
+    glStencilMask(0xFFFFF);
+    glColorMask(GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE);
+}
+
+void Camera::clearBackground(float depth)
+{
+    auto renderer = Director::getInstance()->getRenderer();
+    _beforeClearCommand.init(0,Mat4(),0);
+    _beforeClearCommand.func = CC_CALLBACK_0(Camera::onBeforeClear, this);
+    renderer->addCommand(&_beforeClearCommand);
+    
+    //draw
+    static V3F_C4B_T2F_Quad quad;
+    quad.bl.vertices = Vec3(-1,-1,0);
+    quad.br.vertices = Vec3(1,-1,0);
+    quad.tl.vertices = Vec3(-1,1,0);
+    quad.tr.vertices = Vec3(1,1,0);
+    
+    quad.bl.colors = quad.br.colors = quad.tl.colors = quad.tr.colors = Color4B(0,0,0,1);
+    
+    quad.bl.texCoords = Tex2F(0,0);
+    quad.br.texCoords = Tex2F(1,0);
+    quad.tl.texCoords = Tex2F(0,1);
+    quad.tr.texCoords = Tex2F(1,1);
+    
+    auto shader = GLProgramCache::getInstance()->getGLProgram(GLProgram::SHADER_CAMERA_CLEAR);
+    auto programState = GLProgramState::create(shader);
+    programState->setUniformFloat("depth", 1.0);
+    _clearCommand.init(0, 0, programState, BlendFunc::DISABLE, &quad, 1, Mat4(), 0);
+    renderer->addCommand(&_clearCommand);
+    
+    
+    _endClearCommand.init(0,Mat4(),0);
+    _endClearCommand.func = CC_CALLBACK_0(Camera::onEndClear, this);
+    renderer->addCommand(&_endClearCommand);
+}
+
 NS_CC_END

cocos/2d/CCCamera.h

@@ -26,6 +26,8 @@ THE SOFTWARE.
 
 #include "2d/CCNode.h"
 #include "3d/CCFrustum.h"
+#include "renderer/CCQuadCommand.h"
+#include "renderer/CCCustomCommand.h"
 
 NS_CC_BEGIN
 
@@ -183,7 +185,9 @@ public:
      * Get the default camera of the current running scene.
      */
     static Camera* getDefaultCamera();
-
+    
+    void clearBackground(float depth);
+    
 CC_CONSTRUCTOR_ACCESS:
     Camera();
     ~Camera();
@@ -200,7 +204,7 @@ CC_CONSTRUCTOR_ACCESS:
     bool initDefault();
     bool initPerspective(float fieldOfView, float aspectRatio, float nearPlane, float farPlane);
     bool initOrthographic(float zoomX, float zoomY, float nearPlane, float farPlane);
-
+    
 protected:
 
     Scene* _scene; //Scene camera belongs to
@@ -223,6 +227,15 @@ protected:
     static Camera* _visitingCamera;
     
     friend class Director;
+protected:
+    //callback for clear background
+    void onBeforeClear();
+    void onEndClear();
+    GLboolean _oldDepthTest;
+    GLint _oldDepthFunc;
+    CustomCommand _beforeClearCommand;
+    QuadCommand _clearCommand;
+    CustomCommand _endClearCommand;
 };
 
 NS_CC_END

cocos/2d/CCScene.cpp

@@ -151,6 +151,8 @@ void Scene::render(Renderer* renderer)
         director->pushMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_PROJECTION);
         director->loadMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_PROJECTION, Camera::_visitingCamera->getViewProjectionMatrix());
         
+        //clear background with max depth
+        camera->clearBackground(1.0);
         //visit the scene
         visit(renderer, transform, 0);
         renderer->render();

cocos/renderer/CCGLProgram.cpp

@@ -74,6 +74,7 @@ const char* GLProgram::SHADER_3D_PARTICLE_COLOR = "Shader3DParticleColor";
 const char* GLProgram::SHADER_3D_PARTICLE_TEXTURE = "Shader3DParticleTexture";
 const char* GLProgram::SHADER_3D_SKYBOX = "Shader3DSkybox";
 const char* GLProgram::SHADER_3D_TERRAIN = "Shader3DTerrain";
+const char* GLProgram::SHADER_CAMERA_CLEAR = "ShaderCameraClear";
 
 
 // uniform names

cocos/renderer/CCGLProgram.h

@@ -230,7 +230,11 @@ public:
      Built in shader for terrain
      */
     static const char* SHADER_3D_TERRAIN;
-
+    
+    /**
+     Built in shader for camera clear
+     */
+    static const char* SHADER_CAMERA_CLEAR;
     /**
     end of built shader types.
     @}

cocos/renderer/CCGLProgramCache.cpp

@@ -66,6 +66,7 @@ enum {
     kShaderType_3DParticleColor,
     kShaderType_3DSkyBox,
     kShaderType_3DTerrain,
+    kShaderType_CameraClear,
 #if CC_TARGET_PLATFORM == CC_PLATFORM_WP8 || defined(WP8_SHADER_COMPILER)
     kShaderType_PositionColor_noMVP_GrayScale,
 #endif
@@ -260,6 +261,10 @@ void GLProgramCache::loadDefaultGLPrograms()
     p = new GLProgram();
     loadDefaultGLProgram(p, kShaderType_3DTerrain);
     _programs.insert(std::make_pair(GLProgram::SHADER_3D_TERRAIN, p));
+    
+    p = new GLProgram();
+    loadDefaultGLProgram(p, kShaderType_CameraClear);
+    _programs.insert(std::make_pair(GLProgram::SHADER_CAMERA_CLEAR, p));
 }
 
 void GLProgramCache::reloadDefaultGLPrograms()
@@ -395,6 +400,10 @@ void GLProgramCache::reloadDefaultGLPrograms()
     p = getGLProgram(GLProgram::SHADER_3D_TERRAIN);
     p->reset();
     loadDefaultGLProgram(p, kShaderType_3DTerrain);
+    
+    p = getGLProgram(GLProgram::SHADER_CAMERA_CLEAR);
+    p->reset();
+    loadDefaultGLProgram(p, kShaderType_CameraClear);
 }
 
 void GLProgramCache::loadDefaultGLProgram(GLProgram *p, int type)
@@ -496,6 +505,9 @@ void GLProgramCache::loadDefaultGLProgram(GLProgram *p, int type)
         case kShaderType_3DTerrain:
             p->initWithByteArrays(cc3D_Terrain_vert, cc3D_Terrain_frag);
             break;
+        case kShaderType_CameraClear:
+            p->initWithByteArrays(ccCameraClearVert, ccCameraClearFrag);
+            break;
 #if CC_TARGET_PLATFORM == CC_PLATFORM_WP8 || defined(WP8_SHADER_COMPILER)
         case kShaderType_PositionColor_noMVP_GrayScale:
             p->initWithByteArrays(ccPositionTextureColor_noMVP_vert, ccUIGrayScale_frag);

cocos/renderer/ccShader_CameraClear.frag

@@ -0,0 +1,15 @@
+
+const char* ccCameraClearFrag = STRINGIFY(
+
+\n#ifdef GL_ES\n
+varying mediump vec2 v_texCoord;
+varying mediump vec3 v_color;
+\n#else\n
+varying vec2 v_texCoord;
+varying vec3 v_color;
+\n#endif\n
+void main()
+{
+    gl_FragColor = vec4(v_color, 1.0);
+}
+);

cocos/renderer/ccShader_CameraClear.vert

@@ -0,0 +1,24 @@
+
+const char* ccCameraClearVert = STRINGIFY(
+                                          
+uniform float depth;
+
+attribute vec4 a_position;
+attribute vec2 a_texCoord;
+attribute vec3 a_color;
+\n#ifdef GL_ES\n
+varying mediump vec2 v_texCoord;
+varying mediump vec3 v_color;
+\n#else\n
+varying vec2 v_texCoord;
+varying vec3 v_color;
+\n#endif\n
+void main()
+{
+    gl_Position = a_position;
+    gl_Position.z = depth;
+    gl_Position.w = 1.0;
+    v_texCoord = a_texCoord;
+    v_color = a_color;
+}
+);

cocos/renderer/ccShaders.cpp

@@ -97,5 +97,7 @@ NS_CC_BEGIN
 #include "ccShader_3D_Skybox.frag"
 #include "ccShader_3D_Terrain.vert"
 #include "ccShader_3D_Terrain.frag"
+#include "ccShader_CameraClear.vert"
+#include "ccShader_CameraClear.frag"
 
 NS_CC_END

cocos/renderer/ccShaders.h

@@ -90,8 +90,8 @@ extern CC_DLL const GLchar * cc3D_Skybox_vert;
 extern CC_DLL const GLchar * cc3D_Skybox_frag;
 extern CC_DLL const GLchar * cc3D_Terrain_vert;
 extern CC_DLL const GLchar * cc3D_Terrain_frag;
-
+extern CC_DLL const GLchar * ccCameraClearVert;
-
+extern CC_DLL const GLchar * ccCameraClearFrag;
 NS_CC_END
 /**
  end of support group