source: flair-src/trunk/lib/FlairSimulator/src/SimuCameraGL.cpp@ 9

//  created:    2014/03/07
//  filename:   SimuCameraGL.cpp
//
//  author:     Guillaume Sanahuja
//              Copyright Heudiasyc UMR UTC/CNRS 7253
//              pbo code from Song Ho Ahn (song.ahn@gmail.com)
//
//  version:    $Id: $
//
//  purpose:    Class for a simulation camera
//
//
/*********************************************************************/
#ifdef GL

#include "SimuCameraGL.h"
#include "Model.h"
#include <SharedMem.h>
#include <TabWidget.h>
#include <Tab.h>
#include <DoubleSpinBox.h>
#include <Vector3DSpinBox.h>
#include <Gui.h>
#include <Euler.h>

#include <ISceneManager.h>
#include <ICameraSceneNode.h>
#include <IVideoDriver.h>

#define PBO_COUNT 2

using namespace irr;
using namespace irr::scene;
using namespace irr::core;
using namespace flair::core;
using namespace flair::gui;
using namespace flair::simulator;

namespace flair
{
namespace sensor
{

SimuCameraGL::SimuCameraGL(const Model* parent,std::string name,int width,int height,int x,int y,int dev_id) :SimuCamera(parent,name,width,height,3,dev_id),SensorGL(parent)
{
    smgr=getGui()->getSceneManager();
    camera=smgr->addCameraSceneNode();
    camera->addAnimator(this);
    camera->setAspectRatio(4.0f/3.0f);//on force a cause du view port

    this->width=width;
    this->height=height;
    this->x=x;
    this->y=y;

    index = 0;

    buffer=(char*)malloc(width*height*3);

    //user interface
    Tab* setup_tab=new Tab(parent->GetTabWidget(),name);
        position=new Vector3DSpinBox(setup_tab->NewRow(),"position",-2,2,.01);
        direction=new Vector3DSpinBox(setup_tab->NewRow(),"direction",-2,2,.01);
        up=new Vector3DSpinBox(setup_tab->NewRow(),"up",-2,2,.01);
        fov=new DoubleSpinBox(setup_tab->NewRow(),"fov:",0,180,5);

    if(strcmp((char*)glGetString(GL_VENDOR),"Intel Open Source Technology Center")==0) {
        Thread::Warn("disabling cameras output for Intel card (bug with PBO)\n");
        disable_output=true;
    } else {
        disable_output=false;
    }

    if(isGlExtensionSupported("GL_ARB_pixel_buffer_object"))
    {
        use_pbo=true;
         // create 2 pixel buffer objects, you need to delete them when program exits.
        // glBufferDataARB with NULL pointer reserves only memory space.
        pboIds=(GLuint*)malloc(PBO_COUNT*sizeof(GLuint));
        glGenBuffersARB(PBO_COUNT, pboIds);
        glBindBufferARB(GL_PIXEL_PACK_BUFFER_ARB, pboIds[0]);
        glBufferDataARB(GL_PIXEL_PACK_BUFFER_ARB, width*height*3, 0, GL_STREAM_READ_ARB);
        glBindBufferARB(GL_PIXEL_PACK_BUFFER_ARB, pboIds[1]);
        glBufferDataARB(GL_PIXEL_PACK_BUFFER_ARB, width*height*3, 0, GL_STREAM_READ_ARB);

        glBindBufferARB(GL_PIXEL_PACK_BUFFER_ARB, 0);
    }
    else
    {
        use_pbo=false;
        Thread::Warn("GL_ARB_pixel_buffer_object is not suppoorted\n");
    }
    if(isGlExtensionSupported("GL_PACK_INVERT_MESA"))
    {
        invert_pixel=false;
        Thread::Warn("GL_PACK_INVERT_MESA is suppoorted\n");
    }
    else
    {
        invert_pixel=true;
    }
}

SimuCameraGL::~SimuCameraGL()
{
    free(buffer);

    if(use_pbo)
    {
        glDeleteBuffersARB(PBO_COUNT, pboIds);
        free(pboIds);
    }
}

void SimuCameraGL::setNearValue(float zn) {
    camera->setNearValue(zn);
}


void SimuCameraGL::setFarValue(float zf) {
    camera->setFarValue(zf);
}


void SimuCameraGL::UpdateFrom(const io_data *data)
{
    if(noGui()==false && data==NULL)
    {
        smgr->setActiveCamera(camera);
        smgr->getVideoDriver()->setViewPort(rect<s32>(x,y,x+width,y+height));
        smgr->drawAll();
        //use_pbo=false;
        getImage();
    }
}

void SimuCameraGL::getImage(void)
{
    if(disable_output) return;
    //convert from irrlicht top left origin to gl bottom left origin
    int y=smgr->getVideoDriver()->getScreenSize().Height-height-this->y;

        // We want to read the front buffer to get the latest render finished.
        Time a=GetTime();
        glReadBuffer(GL_FRONT);
        if(use_pbo) // with PBO
    {
        // increment current index first then get the next index
        // "index" is used to read pixels from a framebuffer to a PBO
        // "nextIndex" is used to process pixels in the other PBO
        index = (index + 1) % PBO_COUNT;
        int nextIndex = (index + 1) % PBO_COUNT;

        // copy pixels from framebuffer to PBO
        // Use offset instead of pointer.
        // OpenGL should perform asynch DMA transfer, so glReadPixels() will return immediately.
        glBindBufferARB(GL_PIXEL_PACK_BUFFER_ARB, pboIds[index]);
        glReadPixels(x,y,width,height, GL_BGR, GL_UNSIGNED_BYTE, 0);

        // map the PBO that contain framebuffer pixels before processing it
        glBindBufferARB(GL_PIXEL_PACK_BUFFER_ARB, pboIds[nextIndex]);
        GLubyte* src = (GLubyte*)glMapBufferARB(GL_PIXEL_PACK_BUFFER_ARB,GL_READ_WRITE_ARB);//GL_READ_ONLY_ARB);
        if(src)
        {
            putImage((char*)src);
            glUnmapBufferARB(GL_PIXEL_PACK_BUFFER_ARB);     // release pointer to the mapped buffer
        }
        glBindBufferARB(GL_PIXEL_PACK_BUFFER_ARB, 0);
    }
    else
    {
        glReadPixels(x,y,width,height, GL_BGR, GL_UNSIGNED_BYTE, buffer);
        putImage(buffer);
    }

        glReadBuffer(GL_BACK);
        Time b=GetTime();
        Time c=b-a;
        //printf("%s %f\n",Thread::ObjectName().c_str(),(float)(c/1000000.));
}

void SimuCameraGL::putImage(char* buf)
{
    if(invert_pixel==true)
    {
        // opengl images are horizontally flipped, so we have to fix that here.
        const s32 pitch=width*3;
        char* pixels = buf;
        char* p2 = pixels + (height - 1) * pitch;
        char* tmpBuffer = new char[pitch];
        for (int i=0; i < height; i += 2)
        {
            memcpy(tmpBuffer, pixels, pitch);
            memcpy(pixels, p2, pitch);
            memcpy(p2, tmpBuffer, pitch);
            pixels += pitch;
            p2 -= pitch;
        }
        delete [] tmpBuffer;
    }

    shmem->Write(buf,width*height*3);
}

void SimuCameraGL::animateNode(ISceneNode* node, u32 timeMs)
{
    ICameraSceneNode* camera = static_cast<ICameraSceneNode*>(node);

    matrix4 m;
    m.setRotationDegrees(Node()->getRotation());

    // transform forward vector of camera
    vector3df frv =ToIrrlichtCoordinates(direction->Value());
    m.transformVect(frv);

    // transform upvector of camera
    vector3df upv =ToIrrlichtCoordinates(up->Value());
    m.transformVect(upv);

    // transform camera offset (thanks to Zeuss for finding it was missing)
    vector3df offset = ToIrrlichtCoordinates(position->Value());
    m.transformVect(offset);

    // set camera
    camera->setPosition(Node()->getPosition() + offset); //position camera in front of the ship
    camera->setUpVector(upv); //set up vector of camera >> Zeuss - tested with +node->getPostion() and it didnt work, but this works fine.
    camera->setTarget(Node()->getPosition() + offset+frv); //set target of camera (look at point) >> Zeuss - Dont forget to add the node positiob

    camera->setFOV(Euler::ToRadian(fov->Value()));
}

ISceneNodeAnimator* SimuCameraGL::createClone(ISceneNode* node,
            ISceneManager* newManager)
{
    return NULL;
}

} // end namespace sensor
} // end namespace flair
#endif