PlugIns编程

开发平台：
C/C++

plugin.cpp：源码内容
							/*OpenSceneGraph Firefox-plugin
*License: GPL 2.0
*Based on Work by Mozilla.org and OpenSceneGraph osgviewerGLUT-sample by Robert Osfield
*(c) Andreas Goebel 2008
*/
#include "plugin.h"
#include <gl/gl.h> 
#include <stdlib.h>
#include <Psapi.h>
#include <osgDB/FileUtils>
/*
//Global Variables
osg::ref_ptr<osgViewer::Viewer> viewer;
osg::observer_ptr<osgViewer::GraphicsWindow> window;
char* filename;
*/
//Functions that translate the Windows Mouse-Events to osg-events
void nsPluginInstance::mousebutton( int button, int state, int x, int y )
{
	if (window.valid())
	{
		if (state==0) window->getEventQueue()->mouseButtonPress( x, y, button+1 );
		else window->getEventQueue()->mouseButtonRelease( x, y, button+1 );
	}
}
void nsPluginInstance::mousemove( int x, int y )
{
	if (window.valid())
	{
		window->getEventQueue()->mouseMotion( x, y );
	}
}
//////////////////////////////////////
//
// general initialization and shutdown
//
NPError NS_PluginInitialize()
{
	return NPERR_NO_ERROR;
}
void NS_PluginShutdown()
{
}
/////////////////////////////////////////////////////////////
//
// construction and destruction of our plugin instance object
//
nsPluginInstanceBase * NS_NewPluginInstance(nsPluginCreateData * aCreateDataStruct)
{
	if(!aCreateDataStruct)
		return NULL;
	nsPluginInstance * plugin = new nsPluginInstance(aCreateDataStruct->instance);
	for (int i = 0; i<aCreateDataStruct->argc; ++i){
		if ( strcmp(aCreateDataStruct->argn[i] , "src") == 0)
			plugin->filename = aCreateDataStruct->argv[i]; //This structs holds tha value passed to the plugin with embed
		if ( strcmp(aCreateDataStruct->argn[i] , "width") == 0)
			plugin->width = atoi(aCreateDataStruct->argv[i]) ; 
		if ( strcmp(aCreateDataStruct->argn[i] , "height") == 0)
			plugin->height= atoi(aCreateDataStruct->argv[i]) ; 
		//MessageBox(NULL,aCreateDataStruct->argn[i],aCreateDataStruct->argv[i],MB_OK);	
	}
	DWORD   cchCurDir;
    LPTSTR  lpszCurDir;
    TCHAR   tchBuffer[MAX_PATH + 1];
    //DWORD   nSize;
    lpszCurDir = tchBuffer;
    cchCurDir = MAX_PATH;
    
	HINSTANCE handle =LoadLibrary( "nposgviewer.dll" );
	//std::string dlldir;
	if (handle)
	{
		GetModuleFileName(handle, lpszCurDir, cchCurDir);
		//PathRemoveFileSpec(lpszCurDir);
		FreeLibrary(handle);
		//std::string dir=lpszCurDir;
		//int pos = dir.rfind("\");
		//dlldir = dir.substr(0,pos);*/
		char* lastSlash = strrchr(lpszCurDir, '\');
	    if (lastSlash)
		   *(lastSlash + 1) = ''; 
	}
		//std::string dlldir;
	//MessageBox(NULL, "Verzeichnis", lpszCurDir, MB_OK);
	//std::string bla = lpszCurDir; //Copy?
		//std::deque<std::string>& list2 = osgDB::getLibraryFilePathList();
	osgDB::getLibraryFilePathList().push_front(lpszCurDir);
		//list2.push_front(dlldir);
	//std::deque<std::string> list;
	//list.push_front(dlldir);
	//osgDB::appendPlatformSpecificLibraryFilePaths(list);
	//osgDB::
	//FreeLibrary(handle);
		
	return plugin;
	
}
void NS_DestroyPluginInstance(nsPluginInstanceBase * aPlugin)
{
	if(aPlugin)
		delete (nsPluginInstance *)aPlugin;
}
////////////////////////////////////////
//
// nsPluginInstance class implementation
//
nsPluginInstance::nsPluginInstance(NPP aInstance) : nsPluginInstanceBase(),
mInstance(aInstance),
mInitialized(FALSE)
{
	mhWnd = NULL; width = 400; height = 400; filename=NULL;
}
nsPluginInstance::~nsPluginInstance()
{
}
static LRESULT CALLBACK PluginWinProc(HWND, UINT, WPARAM, LPARAM);
static WNDPROC lpOldProc = NULL;
void EnableOpenGL(HWND hWnd, HDC * hDC, HGLRC * hRC); 
void DisableOpenGL(HWND hWnd, HDC hDC, HGLRC hRC);
/*
HDC hDC;
HGLRC hRC;
*/
NPBool nsPluginInstance::init(NPWindow* aWindow)
{
	if(aWindow == NULL)
		return FALSE;
	mhWnd = (HWND)aWindow->window;
	if(mhWnd == NULL)
		return FALSE;
	// subclass window so we can intercept window messages and
	// do our drawing to it
	lpOldProc = SubclassWindow(mhWnd, (WNDPROC)PluginWinProc);
	// associate window with our nsPluginInstance object so we can access 
	// it in the window procedure
	SetWindowLong(mhWnd, GWL_USERDATA, (LONG)this);
	//we add EnableOpenGL and SetTimer
	EnableOpenGL( mhWnd, &hDC, &hRC );
	SetTimer(mhWnd, 0,  1,  (TIMERPROC) NULL); // no timer callback
	//osg-related code:
	//Node-file is read via http by libcurl:
	std::string s = filename;
	osg::ref_ptr<osg::Node> loadedModel = osgDB::readNodeFile(s);
	viewer = new osgViewer::Viewer;
	float w = (float)width; float h = (float)height; w*=1.1; h*=1.1; width=(int)w; height=(int)h;
	window = viewer->setUpViewerAsEmbeddedInWindow(0,0,width,height);
	viewer->setSceneData(loadedModel.get());
	osg::ref_ptr<osgGA::TrackballManipulator> tbm = new osgGA::TrackballManipulator();
	viewer->setCameraManipulator(tbm.get() );
	osg::ref_ptr<osgViewer::StatsHandler> stats = new osgViewer::StatsHandler();
	viewer->addEventHandler(stats);
	viewer->realize();
	mInitialized = TRUE;
	return TRUE;
}
void nsPluginInstance::shut()
{
	// We add DisableOpenGL
	DisableOpenGL( mhWnd, hDC, hRC );
	// subclass it back
	SubclassWindow(mhWnd, lpOldProc);
	mhWnd = NULL;
	mInitialized = FALSE;
}
NPBool nsPluginInstance::isInitialized()
{
	return mInitialized;
}
const char * nsPluginInstance::getVersion()
{
	return NPN_UserAgent(mInstance);
}
static LRESULT CALLBACK PluginWinProc(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
	nsPluginInstance* inst = (nsPluginInstance*)GetWindowLong(hWnd, GWL_USERDATA);
	HDC hDC = inst->hDC;
	HGLRC hRC = inst->hRC;
	switch (msg) {
	case WM_PAINT:
		{
			wglMakeCurrent( hDC, hRC );
			if (inst->viewer.valid()) inst->viewer->frame();
			SwapBuffers( hDC );
		}
		break;
	case WM_TIMER:
		PostMessage( hWnd, WM_PAINT, NULL, NULL );
		break;    
	case WM_LBUTTONDOWN:
		{
			short xp = LOWORD(lParam);
			short yp = HIWORD(lParam);			
			inst->mousebutton(0,0,xp,yp);
			break;
		}
	case WM_LBUTTONUP:
		{
			short xp = LOWORD(lParam);
			short yp = HIWORD(lParam);
			inst->mousebutton(0,1,xp,yp);
			break;
		}
	case WM_RBUTTONDOWN:
		{
			short xp = LOWORD(lParam);
			short yp = HIWORD(lParam);			
			inst->mousebutton(2,0,xp,yp);
		}
		break;
	case WM_RBUTTONUP:
		{
			short xp = LOWORD(lParam);
			short yp = HIWORD(lParam);
			inst->mousebutton(2,1,xp,yp);
			break;
		}
	case WM_MOUSEMOVE:
		{
			short xp = LOWORD(lParam);
			short yp = HIWORD(lParam);
			inst->mousemove(xp,yp);
			break;
		}
	default:
		break;
	}
	return DefWindowProc(hWnd, msg, wParam, lParam);
}
void EnableOpenGL(HWND hWnd, HDC * hDC, HGLRC * hRC)
{
	PIXELFORMATDESCRIPTOR pfd;
	int format;
	// get the device context (DC)
	*hDC = GetDC( hWnd ); // set the pixel format for the DC
	ZeroMemory( &pfd, sizeof( pfd ) );
	pfd.nSize = sizeof( pfd );
	pfd.nVersion = 1; 
	pfd.dwFlags = PFD_DRAW_TO_WINDOW | PFD_SUPPORT_OPENGL | 
		PFD_DOUBLEBUFFER;
	pfd.iPixelType = PFD_TYPE_RGBA;
	pfd.cColorBits = 24;
	pfd.cDepthBits = 16;
	pfd.iLayerType = PFD_MAIN_PLANE;
	format = ChoosePixelFormat( *hDC, &pfd );
	SetPixelFormat( *hDC, format, &pfd );
	// create and enable the render context (RC)
	*hRC = wglCreateContext( *hDC ); 
	wglMakeCurrent( *hDC, *hRC );
}
// Disable OpenGL
void DisableOpenGL(HWND hWnd, HDC hDC, HGLRC hRC)
{
	wglMakeCurrent( NULL, NULL );
	wglDeleteContext( hRC );
	ReleaseDC( hWnd, hDC );
}    

						