axmol/cocos/2d/CCClippingNode.cpp

479 lines
14 KiB
C++

/*
* Copyright (c) 2012 Pierre-David Bélanger
* Copyright (c) 2012 cocos2d-x.org
* Copyright (c) 2013-2014 Chukong Technologies Inc.
*
* cocos2d-x: http://www.cocos2d-x.org
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*
*/
#include "CCClippingNode.h"
#include "CCGLProgram.h"
#include "CCShaderCache.h"
#include "CCDirector.h"
#include "CCDrawingPrimitives.h"
#include "renderer/CCRenderer.h"
#include "renderer/CCGroupCommand.h"
#include "renderer/CCCustomCommand.h"
NS_CC_BEGIN
static GLint g_sStencilBits = -1;
// store the current stencil layer (position in the stencil buffer),
// this will allow nesting up to n ClippingNode,
// where n is the number of bits of the stencil buffer.
static GLint s_layer = -1;
static void setProgram(Node *n, GLProgram *p)
{
n->setShaderProgram(p);
auto& children = n->getChildren();
for(const auto &child : children) {
setProgram(child, p);
}
}
ClippingNode::ClippingNode()
: _stencil(nullptr)
, _alphaThreshold(0.0f)
, _inverted(false)
, _currentStencilEnabled(GL_FALSE)
, _currentStencilWriteMask(~0)
, _currentStencilFunc(GL_ALWAYS)
, _currentStencilRef(0)
, _currentStencilValueMask(~0)
, _currentStencilFail(GL_KEEP)
, _currentStencilPassDepthFail(GL_KEEP)
, _currentStencilPassDepthPass(GL_KEEP)
, _currentDepthWriteMask(GL_TRUE)
, _currentAlphaTestEnabled(GL_FALSE)
, _currentAlphaTestFunc(GL_ALWAYS)
, _currentAlphaTestRef(1)
{
}
ClippingNode::~ClippingNode()
{
if (_stencil)
{
_stencil->stopAllActions();
_stencil->release();
}
}
ClippingNode* ClippingNode::create()
{
ClippingNode *ret = new ClippingNode();
if (ret && ret->init())
{
ret->autorelease();
}
else
{
CC_SAFE_DELETE(ret);
}
return ret;
}
ClippingNode* ClippingNode::create(Node *pStencil)
{
ClippingNode *ret = new ClippingNode();
if (ret && ret->init(pStencil))
{
ret->autorelease();
}
else
{
CC_SAFE_DELETE(ret);
}
return ret;
}
bool ClippingNode::init()
{
return init(nullptr);
}
bool ClippingNode::init(Node *stencil)
{
CC_SAFE_RELEASE(_stencil);
_stencil = stencil;
CC_SAFE_RETAIN(_stencil);
_alphaThreshold = 1;
_inverted = false;
// get (only once) the number of bits of the stencil buffer
static bool once = true;
if (once)
{
glGetIntegerv(GL_STENCIL_BITS, &g_sStencilBits);
if (g_sStencilBits <= 0)
{
CCLOG("Stencil buffer is not enabled.");
}
once = false;
}
return true;
}
void ClippingNode::onEnter()
{
Node::onEnter();
if (_stencil != nullptr)
{
_stencil->onEnter();
}
else
{
CCLOG("ClippingNode warning: _stencil is nil.");
}
}
void ClippingNode::onEnterTransitionDidFinish()
{
Node::onEnterTransitionDidFinish();
if (_stencil != nullptr)
{
_stencil->onEnterTransitionDidFinish();
}
}
void ClippingNode::onExitTransitionDidStart()
{
if (_stencil != nullptr)
{
_stencil->onExitTransitionDidStart();
}
Node::onExitTransitionDidStart();
}
void ClippingNode::onExit()
{
if (_stencil != nullptr)
{
_stencil->onExit();
}
Node::onExit();
}
void ClippingNode::drawFullScreenQuadClearStencil()
{
Director* director = Director::getInstance();
CCASSERT(nullptr != director, "Director is null when seting matrix stack");
director->pushMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_MODELVIEW);
director->loadIdentityMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_MODELVIEW);
director->pushMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_PROJECTION);
director->loadIdentityMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_PROJECTION);
DrawPrimitives::drawSolidRect(Vector2(-1,-1), Vector2(1,1), Color4F(1, 1, 1, 1));
director->popMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_PROJECTION);
director->popMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_MODELVIEW);
}
void ClippingNode::visit(Renderer *renderer, const Matrix &parentTransform, bool parentTransformUpdated)
{
if(!_visible)
return;
bool dirty = parentTransformUpdated || _transformUpdated;
if(dirty)
_modelViewTransform = transform(parentTransform);
_transformUpdated = false;
// IMPORTANT:
// To ease the migration to v3.0, we still support the Matrix stack,
// but it is deprecated and your code should not rely on it
Director* director = Director::getInstance();
CCASSERT(nullptr != director, "Director is null when seting matrix stack");
director->pushMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_MODELVIEW);
director->loadMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_MODELVIEW, _modelViewTransform);
//Add group command
_groupCommand.init(_globalZOrder);
renderer->addCommand(&_groupCommand);
renderer->pushGroup(_groupCommand.getRenderQueueID());
_beforeVisitCmd.init(_globalZOrder);
_beforeVisitCmd.func = CC_CALLBACK_0(ClippingNode::onBeforeVisit, this);
renderer->addCommand(&_beforeVisitCmd);
if (_alphaThreshold < 1)
{
#if (CC_TARGET_PLATFORM == CC_PLATFORM_MAC || CC_TARGET_PLATFORM == CC_PLATFORM_WINDOWS || CC_TARGET_PLATFORM == CC_PLATFORM_LINUX)
#else
// since glAlphaTest do not exists in OES, use a shader that writes
// pixel only if greater than an alpha threshold
GLProgram *program = ShaderCache::getInstance()->getProgram(GLProgram::SHADER_NAME_POSITION_TEXTURE_ALPHA_TEST_NO_MV);
GLint alphaValueLocation = glGetUniformLocation(program->getProgram(), GLProgram::UNIFORM_NAME_ALPHA_TEST_VALUE);
// set our alphaThreshold
program->use();
program->setUniformLocationWith1f(alphaValueLocation, _alphaThreshold);
// we need to recursively apply this shader to all the nodes in the stencil node
// XXX: we should have a way to apply shader to all nodes without having to do this
setProgram(_stencil, program);
#endif
}
_stencil->visit(renderer, _modelViewTransform, dirty);
_afterDrawStencilCmd.init(_globalZOrder);
_afterDrawStencilCmd.func = CC_CALLBACK_0(ClippingNode::onAfterDrawStencil, this);
renderer->addCommand(&_afterDrawStencilCmd);
int i = 0;
if(!_children.empty())
{
sortAllChildren();
// draw children zOrder < 0
for( ; i < _children.size(); i++ )
{
auto node = _children.at(i);
if ( node && node->getLocalZOrder() < 0 )
node->visit(renderer, _modelViewTransform, dirty);
else
break;
}
// self draw
this->draw(renderer, _modelViewTransform, dirty);
for(auto it=_children.cbegin()+i; it != _children.cend(); ++it)
(*it)->visit(renderer, _modelViewTransform, dirty);
}
else
{
this->draw(renderer, _modelViewTransform, dirty);
}
_afterVisitCmd.init(_globalZOrder);
_afterVisitCmd.func = CC_CALLBACK_0(ClippingNode::onAfterVisit, this);
renderer->addCommand(&_afterVisitCmd);
renderer->popGroup();
director->popMatrix(MATRIX_STACK_TYPE::MATRIX_STACK_MODELVIEW);
}
Node* ClippingNode::getStencil() const
{
return _stencil;
}
void ClippingNode::setStencil(Node *stencil)
{
CC_SAFE_RETAIN(stencil);
CC_SAFE_RELEASE(_stencil);
_stencil = stencil;
}
GLfloat ClippingNode::getAlphaThreshold() const
{
return _alphaThreshold;
}
void ClippingNode::setAlphaThreshold(GLfloat alphaThreshold)
{
_alphaThreshold = alphaThreshold;
}
bool ClippingNode::isInverted() const
{
return _inverted;
}
void ClippingNode::setInverted(bool inverted)
{
_inverted = inverted;
}
void ClippingNode::onBeforeVisit()
{
///////////////////////////////////
// INIT
// increment the current layer
s_layer++;
// mask of the current layer (ie: for layer 3: 00000100)
GLint mask_layer = 0x1 << s_layer;
// mask of all layers less than the current (ie: for layer 3: 00000011)
GLint mask_layer_l = mask_layer - 1;
// mask of all layers less than or equal to the current (ie: for layer 3: 00000111)
_mask_layer_le = mask_layer | mask_layer_l;
// manually save the stencil state
_currentStencilEnabled = glIsEnabled(GL_STENCIL_TEST);
glGetIntegerv(GL_STENCIL_WRITEMASK, (GLint *)&_currentStencilWriteMask);
glGetIntegerv(GL_STENCIL_FUNC, (GLint *)&_currentStencilFunc);
glGetIntegerv(GL_STENCIL_REF, &_currentStencilRef);
glGetIntegerv(GL_STENCIL_VALUE_MASK, (GLint *)&_currentStencilValueMask);
glGetIntegerv(GL_STENCIL_FAIL, (GLint *)&_currentStencilFail);
glGetIntegerv(GL_STENCIL_PASS_DEPTH_FAIL, (GLint *)&_currentStencilPassDepthFail);
glGetIntegerv(GL_STENCIL_PASS_DEPTH_PASS, (GLint *)&_currentStencilPassDepthPass);
// enable stencil use
glEnable(GL_STENCIL_TEST);
// check for OpenGL error while enabling stencil test
CHECK_GL_ERROR_DEBUG();
// all bits on the stencil buffer are readonly, except the current layer bit,
// this means that operation like glClear or glStencilOp will be masked with this value
glStencilMask(mask_layer);
// manually save the depth test state
glGetBooleanv(GL_DEPTH_WRITEMASK, &_currentDepthWriteMask);
// disable depth test while drawing the stencil
//glDisable(GL_DEPTH_TEST);
// disable update to the depth buffer while drawing the stencil,
// as the stencil is not meant to be rendered in the real scene,
// it should never prevent something else to be drawn,
// only disabling depth buffer update should do
glDepthMask(GL_FALSE);
///////////////////////////////////
// CLEAR STENCIL BUFFER
// manually clear the stencil buffer by drawing a fullscreen rectangle on it
// setup the stencil test func like this:
// for each pixel in the fullscreen rectangle
// never draw it into the frame buffer
// if not in inverted mode: set the current layer value to 0 in the stencil buffer
// if in inverted mode: set the current layer value to 1 in the stencil buffer
glStencilFunc(GL_NEVER, mask_layer, mask_layer);
glStencilOp(!_inverted ? GL_ZERO : GL_REPLACE, GL_KEEP, GL_KEEP);
// draw a fullscreen solid rectangle to clear the stencil buffer
//ccDrawSolidRect(Vector2::ZERO, ccpFromSize([[Director sharedDirector] winSize]), Color4F(1, 1, 1, 1));
drawFullScreenQuadClearStencil();
///////////////////////////////////
// DRAW CLIPPING STENCIL
// setup the stencil test func like this:
// for each pixel in the stencil node
// never draw it into the frame buffer
// if not in inverted mode: set the current layer value to 1 in the stencil buffer
// if in inverted mode: set the current layer value to 0 in the stencil buffer
glStencilFunc(GL_NEVER, mask_layer, mask_layer);
glStencilOp(!_inverted ? GL_REPLACE : GL_ZERO, GL_KEEP, GL_KEEP);
// enable alpha test only if the alpha threshold < 1,
// indeed if alpha threshold == 1, every pixel will be drawn anyways
if (_alphaThreshold < 1) {
#if (CC_TARGET_PLATFORM == CC_PLATFORM_MAC || CC_TARGET_PLATFORM == CC_PLATFORM_WINDOWS || CC_TARGET_PLATFORM == CC_PLATFORM_LINUX)
// manually save the alpha test state
_currentAlphaTestEnabled = glIsEnabled(GL_ALPHA_TEST);
glGetIntegerv(GL_ALPHA_TEST_FUNC, (GLint *)&_currentAlphaTestFunc);
glGetFloatv(GL_ALPHA_TEST_REF, &_currentAlphaTestRef);
// enable alpha testing
glEnable(GL_ALPHA_TEST);
// check for OpenGL error while enabling alpha test
CHECK_GL_ERROR_DEBUG();
// pixel will be drawn only if greater than an alpha threshold
glAlphaFunc(GL_GREATER, _alphaThreshold);
#else
#endif
}
//Draw _stencil
}
void ClippingNode::onAfterDrawStencil()
{
// restore alpha test state
if (_alphaThreshold < 1)
{
#if (CC_TARGET_PLATFORM == CC_PLATFORM_MAC || CC_TARGET_PLATFORM == CC_PLATFORM_WINDOWS || CC_TARGET_PLATFORM == CC_PLATFORM_LINUX)
// manually restore the alpha test state
glAlphaFunc(_currentAlphaTestFunc, _currentAlphaTestRef);
if (!_currentAlphaTestEnabled)
{
glDisable(GL_ALPHA_TEST);
}
#else
// XXX: we need to find a way to restore the shaders of the stencil node and its childs
#endif
}
// restore the depth test state
glDepthMask(_currentDepthWriteMask);
//if (currentDepthTestEnabled) {
// glEnable(GL_DEPTH_TEST);
//}
///////////////////////////////////
// DRAW CONTENT
// setup the stencil test func like this:
// for each pixel of this node and its childs
// if all layers less than or equals to the current are set to 1 in the stencil buffer
// draw the pixel and keep the current layer in the stencil buffer
// else
// do not draw the pixel but keep the current layer in the stencil buffer
glStencilFunc(GL_EQUAL, _mask_layer_le, _mask_layer_le);
glStencilOp(GL_KEEP, GL_KEEP, GL_KEEP);
// draw (according to the stencil test func) this node and its childs
}
void ClippingNode::onAfterVisit()
{
///////////////////////////////////
// CLEANUP
// manually restore the stencil state
glStencilFunc(_currentStencilFunc, _currentStencilRef, _currentStencilValueMask);
glStencilOp(_currentStencilFail, _currentStencilPassDepthFail, _currentStencilPassDepthPass);
glStencilMask(_currentStencilWriteMask);
if (!_currentStencilEnabled)
{
glDisable(GL_STENCIL_TEST);
}
// we are done using this layer, decrement
s_layer--;
}
NS_CC_END