Raycasting with Irrbullet

[eejin]

hi,

bullet obj deactivate after a few seconds so you must active them explicit or disable the deactivation

eg

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body->setActivationState(EAS_DISABLE_DEACTIVATION)
 

Thanks it works . Now how would I get a cilinder as a collisionshape ?

[zerochen]

it is not so hard to implement one yourself

here is a example of my createShape function (note: functionnames dont match to irrBullet)

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void CCylinderShape::createShape()
{
    node->updateAbsolutePosition();
 
    const core::vector3df& extent = node->getBoundingBox().getExtent();
 
    shape = new btCylinderShape(irrlichtToBulletVector(extent * 0.5));
 
    shape->setLocalScaling(irrlichtToBulletVector(node->getScale()));
    calculateLocalInertia(mass, core::vector3df(0.0f,0.0f,0.0f));
}

[eejin]

Im not quite sure how to implement this. Could you maybe point me in the right direction ?
Also is there a function in irrbullet to lock rotations on certain axis?

[zerochen]

have a look at boxshape.h/.cpp
you have to to copy these files, rename it and replace the createShape function.

allow Y rotation:

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rigidBody->setAngularFactor(vector3df(0,1,0));
 

[eejin]

Mhmm I get these errors:

cpp Code: Select all

C:\Users\Person\Documents\Irrlicht\irrlicht-1.7.2\examples\01.HelloWorld\main.cpp||In function 'int main()':|
C:\Users\Person\Documents\Irrlicht\irrlicht-1.7.2\examples\01.HelloWorld\main.cpp|54|error: expected type-specifier before 'CCylinderShape'|
C:\Users\Person\Documents\Irrlicht\irrlicht-1.7.2\examples\01.HelloWorld\main.cpp|54|error: cannot convert 'int*' to 'ICollisionShape*' in initialization|
C:\Users\Person\Documents\Irrlicht\irrlicht-1.7.2\examples\01.HelloWorld\main.cpp|54|error: expected ',' or ';' before 'CCylinderShape'|
||=== Build finished: 3 errors, 3 warnings ===|

With
cylindershape.cpp

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#include <ISceneNode.h>
#include "Bullet/btBulletDynamicsCommon.h"
#include "Bullet/btBulletCollisionCommon.h"
#include "cylindershape.h"
 
using namespace irr;
using namespace core;
using namespace scene;
 
CCylinderShape::CCylinderShape(ISceneNode* const n, f32 m, bool overrideMargin)
{
    node = n;
    mass = m;
 
    type = ECST_BOX;
 
    createShape(overrideMargin);
}
 
 
void CCylinderShape::createShape()
{
    node->updateAbsolutePosition();
 
    const vector3df& extent = node->getBoundingBox().getExtent();
 
    shape = new btCylinderShape(irrlichtToBulletVector(extent * 0.5));
 
    setLocalScaling(node->getScale(), ESP_COLLISIONSHAPE);
    calculateLocalInertia(mass, vector3df(0.0f,0.0f,0.0f));
}
 
CCylinderShape::~CCylinderShape()
{
}
 

and cylindershape.h

cpp Code: Select all

// Copyright (C) 2009-2011 Josiah Hartzell (Skyreign Software)
// This file is part of the "irrBullet" Bullet physics extension library and wrapper.
// For conditions of distribution and use, see license in irrbullet.h
// The above copyright notice and its accompanying information must remain here.
 
#ifndef __CYLINDER_SHAPE_H_INCLUDED__
#define __CYLINDER_SHAPE_H_INCLUDED__
 
#include "collisionshape.h"
 
 
class CCylinderShape : public ICollisionShape
{
public:
    CCylinderShape(irr::scene::ISceneNode* const n, irr::f32 m, bool overrideMargin = false);
 
    virtual ~CCylinderShape();
 
protected:
    void createShape(bool overrideMargin);
};
 
 
#endif // __CYLINDER_SHAPE_H_INCLUDED__
 
 

And I call it like this:

cpp Code: Select all

       ICollisionShape *playershape = new CCylinderShape(player, 1, false);

When I replace CCylinderShape with IBoxShape it compiles and works but as a box shape ofcourse.

And it now only rotates around the y axis but how can I set the pivot point?

[zerochen]

it looks good

only a few things to do:

- #include <BulletCollision/CollisionShapes/btCylinderShape.h> is missing in cylindershape.cpp
- delete bool overrideMargin from the constructor aswell from the createShape function call

- #include "CCylinderShape.h" in irrbullet.h

also after that you have to recompile the irrbullet.lib

Edit:
oh wait you dont have to delete overrideMargin instead add the parameter to the createShape function

[eejin]

It seems to compile fine but where do I find it. I use code::blocks does that matter?

[zerochen]

i dont use code blocks so i cant tell you that.

if recompile works you might find the libs in <irrBullet>\lib folder

[eejin]

I get the errors

||=== Irrlicht Example 01 Hello World, Windows ===|
C:\Users\Stijn\Documents\Irrlicht\irrBullet-0.1.8\source\irrBullet.h|51|warning: missing terminating " character|
C:\Users\Stijn\Documents\Irrlicht\irrBullet-0.1.8\source\irrBullet.h|51|error: #include expects "FILENAME" or <FILENAME>|
C:\Users\Stijn\Documents\Irrlicht\irrlicht-1.7.2\examples\01.HelloWorld\main.cpp||In function 'int main()':|
C:\Users\Stijn\Documents\Irrlicht\irrlicht-1.7.2\examples\01.HelloWorld\main.cpp|69|error: expected type-specifier before 'CCylinderShape'|
C:\Users\Stijn\Documents\Irrlicht\irrlicht-1.7.2\examples\01.HelloWorld\main.cpp|69|error: cannot convert 'int*' to 'ICollisionShape*' in initialization|
C:\Users\Stijn\Documents\Irrlicht\irrlicht-1.7.2\examples\01.HelloWorld\main.cpp|69|error: expected ',' or ';' before 'CCylinderShape'|
||=== Build finished: 4 errors, 4 warnings ===|

[zerochen]

what is in line 51 in irrbullet.h?

where is a error. maybe a missing "?

[eejin]

what is in line 51 in irrbullet.h?

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#include "CCylinderShape.h

where is a error. maybe a missing "?

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ICollisionShape *Floorshape = new CCylinderShape(Floor, 0, false);

[zerochen]

hm, dude you forgot a " -> #include "CCylinderShape.h"

[eejin]

How do you mean? I included it in irrbullet.h.

[eejin]

Mhmm I misunderstood what you meant but now fixed it. Although I get this error message now:

cpp Code: Select all

C:\Users\Stijn\Documents\Irrlicht\irrlicht-1.7.2\examples\01.HelloWorld\main.cpp|69|undefined reference to `CCylinderShape::CCylinderShape(irr::scene::ISceneNode*, float)'|

When I call it like this:

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ICollisionShape *Floorshape = new CCylinderShape(Floor, 0);

But it seems to recognise the function because when I call

cpp Code: Select all

ICollisionShape *Floorshape = new CCylinderShape(Floor, 0,false);

I get this:

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C:\Users\Stijn\Documents\Irrlicht\irrlicht-1.7.2\examples\01.HelloWorld\main.cpp||In function 'int main()':|
C:\Users\Stijn\Documents\Irrlicht\irrlicht-1.7.2\examples\01.HelloWorld\main.cpp|69|error: no matching function for call to 'CCylinderShape::CCylinderShape(irr::scene::ISceneNode*&, int, bool)'|
C:\Users\Stijn\Documents\Irrlicht\irrBullet-0.1.8\source\cylindershape.h|15|note: candidates are: CCylinderShape::CCylinderShape(irr::scene::ISceneNode*, irr::f32)|
C:\Users\Stijn\Documents\Irrlicht\irrBullet-0.1.8\source\cylindershape.h|13|note:                 CCylinderShape::CCylinderShape(const CCylinderShape&)|
||=== Build finished: 1 errors, 3 warnings ===|
 

[zerochen]

also after that you have to recompile the irrbullet.lib

yeah always told you that you have to recompile irrbullet.
open project file from irrbullet folder add the cylindershape files to the proj and push compiling^^