how to rotate Texture2D in cocos2d-iphone - cocos2d-iphone

I'm making a game using cocos2d-iphone, I want's to rotate a Texture2D of maybe 20 degrees, what can I do?
I tried glRotate(20.0f, 0.0f, 0.0f, 1.0f), but it doesn't work.
So any ideas?

Use the CCSprite property rotation
CCSprite* sprite = [CCSprite spriteWithTexture:texture];
sprite.position = ccp(100,100);
sprite.rotation = 20;
[scene addChild:sprite];

Related

How to make a physical wall using cocos2d / chipmunk?

How to make a physical wall using cocos2d / chipmunk ? So that sprite just can not go throught another one sprite(wall)? Sorry,if it's already answered somewhere, I can't find any information for beginners.
This is from cocos2d/chipmunk template. Your sprite should be on chipmunk body, to get that change position of sprite to position of body in your update method.
CGSize s = [[CCDirector sharedDirector] winSize];
_space = cpSpaceNew();
cpSpaceSetGravity( _space, cpv(0, -100) );
//
// rogue shapes
// We have to free them manually
//
// bottom
_walls[0] = cpSegmentShapeNew( _space->staticBody, cpv(0,0), cpv(s.width,0), 0.0f);
// top
_walls[1] = cpSegmentShapeNew( _space->staticBody, cpv(0,s.height), cpv(s.width,s.height), 0.0f);
// left
_walls[2] = cpSegmentShapeNew( _space->staticBody, cpv(0,0), cpv(0,s.height), 0.0f);
// right
_walls[3] = cpSegmentShapeNew( _space->staticBody, cpv(s.width,0), cpv(s.width,s.height), 0.0f);
for( int i=0;i<4;i++) {
cpShapeSetElasticity( _walls[i], 1.0f );
cpShapeSetFriction( _walls[i], 1.0f );
cpSpaceAddStaticShape(_space, _walls[i] );
}

How can I make a rectangular on the moving sprite in Cocos2d android?

CGRect targetRect = CGRect.make(target.getPosition().x - (target.getContentSize().width),
target.getPosition().y - (target.getContentSize().height),
target.getContentSize().width,
target.getContentSize().height);
target is a sprite ... and I make to create a rectangular on the border of the sprite.
I tried to do this work by draw(GL10 gl) but I'm not getting the way to call it .
So, If someone have an idea how to do this . Please help me out of this... thanks in advance
public void draw(GL10 gl){
gl.glColor4f(0.0f, 0.0f, 1.0f, 1.0f);
gl.glLineWidth(4);
CCDrawingPrimitives.ccDrawCircle(gl, centerAnchor, 20*scaleX, ccMacros.CC_DEGREES_TO_RADIANS(90), 50, true);
CCDrawingPrimitives.ccDrawCircle(gl, CGPoint.make((handposition.x-40f)*scaleX,(handposition.y+10f)*scaleY), 45*scaleX, ccMacros.CC_DEGREES_TO_RADIANS(90), 50, true);
CCDrawingPrimitives.ccDrawPoint(gl, centerAnchor);
gl.glLineWidth(1);
gl.glColor4f(1.0f, 1.0f, 1.0f, 1.0f);
gl.glPointSize(1);
}
similarly you can draw rectangle by using ccDrawRect() method

Making a hole on a CCRenderTexture

I am trying to make a hole on a CCRenderTexture with Cocos2D 2.0.
More specifically I have:
a CCSprite "stars" that shows some stars repeating a png image;
on top of that I have a CCRenderTexture "dark" that completely covers the "stars" sprite.
I want to be able to cut a hole on "dark" in order to show the stars below.
I am using CCRenderTexture (as suggested in some tutorials) but the hole I manage to make is never fully transparent, so the stars visible through the hole are partially obscured.
I really hope some one can show me the light, I spent over a week on this...
This is the code:
#interface MyBackgroundLayer : CCLayerGradient {
}
#end
#implementation MyBackgroundLayer
CCRenderTexture * dark;
CCSprite * stars;
-(id) init
{
if (self=[super init]) {
CGSize size = [[CCDirector sharedDirector] winSize];
// background
stars = [CCSprite spriteWithFile:#"stars.png" rect:CGRectMake(0, 0, size.width, size.height)];
stars.anchorPoint = ccp(0,0);
ccTexParams params = {GL_LINEAR,GL_LINEAR,GL_REPEAT,GL_REPEAT};
[stars.texture setTexParameters:&params];
[self addChild:stars];
// dark layer to cover the background
dark = [CCRenderTexture renderTextureWithWidth:size.width height:size.height];
[dark clear:0 g:0 b:0 a:1.0f];
[self addChild: dark];
dark.position = ccp(size.width/2,size.height/2);
[[dark sprite] setBlendFunc: (ccBlendFunc) { GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA }];
}
return self;
}
-(void)draw
{
[super draw];
[dark beginWithClear:0 g:0 b:0 a:1];
glColorMask(0, 0, 0, 1);
// Here I am using 0.5 as alpha value, this could seems the reason why the hole is not fully transparent.
// However if I change the alpha value to 1.0f or 0.0f the hole becomes completely opaque
ccColor4F color = ccc4f(1.f, 1.f, 1.f, 0.5f);
ccDrawSolidRect(ccp(0,0), ccp(600, 600), color);
glColorMask(1,1,1,1);
[dark end];
}
#end
I think what you're looking for is something like this ( may need some editing).
As for your code ..i thing the problem is in the blend function. Check this out to see how they work.

OpenSceneGraph - How to add a Wall or 3

I need to add a wall to my scenegraph, and have it work so I can not go past the wall with my camera. I am creating an laboratory scene, but I am new to 3d programming in general. I have been working with the book OpensceneGraph 3.0 Beginner's guide, and so far, Ok.
I have a couple of furniture in my scene but what I would like to do is add a wall beyond which my camera should not go. My code below, from the book, Openscenegraph beginner, does not seem to do anything(page 83). I add it and I don't see a wall and I am still able to move everywhere in the scene with my camera. How do I create a wall in my application.
osg::ref_ptr<osg::Group> root = new osg::Group();
//adding walls to the lab to make it more room like -- 7/6/12
osg::ref_ptr<osg::Vec3Array> vertices = new osg::Vec3Array;
vertices->push_back(osg::Vec3(0.0f, 0.0f, 0.0f));
vertices->push_back(osg::Vec3(0.0f, 0.0f, 1.0f));
vertices->push_back(osg::Vec3(1.0f, 0.0f, 0.0f));
vertices->push_back(osg::Vec3(1.0f, 0.0f, 1.5f));
vertices->push_back(osg::Vec3(2.0f, 0.0f, 0.0f));
vertices->push_back(osg::Vec3(2.0f, 0.0f, 1.0f));
vertices->push_back(osg::Vec3(3.0f, 0.0f, 0.0f));
vertices->push_back(osg::Vec3(3.0f, 0.0f, 1.5f));
vertices->push_back(osg::Vec3(4.0f, 0.0f, 0.0f));
vertices->push_back(osg::Vec3(4.0f, 0.0f, 1.0f));
osg::ref_ptr<osg::Vec3Array> normals = new osg::Vec3Array;
normals->push_back(osg::Vec3(0.0f, -1.0f, 0.0f));
osg::ref_ptr<osg::Geometry>geom = new osg::Geometry;
geom->setVertexArray(vertices.get());
geom->setNormalArray((normals.get()));
geom->setNormalBinding((osg::Geometry::BIND_OVERALL));
geom->addPrimitiveSet((new osg::DrawArrays(GL_QUAD_STRIP,0,10)));
osg::ref_ptr<osg::Geode> wall = new osg::Geode;
wall->addDrawable(geom.get());
root->addChild(wall);
osgViewer::Viewer viewer;
viewer.setSceneData(root.get());
viewer.run();
You are already drawing the "wall" as coded above - it looks a little more like a fence than a wall, but you can easily fix that by moving the 1.0 values all the way up to 1.5 to match the others. You might not be seeing it with the rest of your scene because of differences of scale - if the dimensions of your furniture are in 100's, for example. Replace your root->addChild(wall) with this code:
// assumes your furniture is already added to root
float scale=root->getBound().radius();
osg::ref_ptr<osg::PositionAttitudeTransform> pax = new osg::PositionAttitudeTransform;
pax->addChild(wall);
pax->setScale(osg::Vec3d(scale,scale,scale));
root->addChild(pax);
Then you will see your fence. Move the position/rotation of pax to place your wall. As I mentioned in the comments, then you'll have to use some intersection code to tell the camera where to stop.

Box2D debug test

I have a problem with Box2d. I created an object (circle) in the center of the screen that rotates to see if I set Box2d well, following the tutorial that I found on internet. The problem is that the circle is created, but I can't rotate despite I followed exactly the tutorial found on internet. This is the code:
file .h:
b2World * _world;
GLESDebugDraw * _debugDraw;
file .mm:
-(void)setupWorld {
b2Vec2 gravity = b2Vec2(0.0f, 0.0f);
bool doSleep = false;
_world = new b2World(gravity, doSleep);
}
-(void)setupDebugDraw {
_debugDraw = new GLESDebugDraw(PTM_RATIO*[[CCDirector sharedDirector] contentScaleFactor]);
_world->SetDebugDraw(_debugDraw);
_debugDraw->SetFlags(b2DebugDraw::e_shapeBit |b2DebugDraw::e_jointBit);
}
-(void)testBox2D {
CGSize winSize = [CCDirector sharedDirector].winSize;
b2BodyDef bodyDef;
bodyDef.type = b2_dynamicBody;
bodyDef.position = b2Vec2(winSize.width/2/PTM_RATIO,winSize.height/2/PTM_RATIO);
b2Body *body = _world->CreateBody(&bodyDef);
b2CircleShape circleShape;
circleShape.m_radius = 25.0/PTM_RATIO;
b2FixtureDef fixtureDef;
fixtureDef.shape = &circleShape;
fixtureDef.density = 1.0;
body->CreateFixture(&fixtureDef);
body->ApplyAngularImpulse(0.01);
}
-(void)updateBox2D:(ccTime)dt {
_world->Step(dt, 1, 1);
[self updateBox2D:dt];
}
-(void) draw {
glDisable(GL_TEXTURE_2D); glDisableClientState(GL_COLOR_ARRAY); glDisableClientState(GL_TEXTURE_COORD_ARRAY);
_world->DrawDebugData();
glEnable(GL_TEXTURE_2D); glEnableClientState(GL_COLOR_ARRAY); glEnableClientState(GL_TEXTURE_COORD_ARRAY);
}

in init:
[self setupWorld];
[self setupDebugDraw];
[self testBox2D];
Two problems:
Are you recursively calling updateBox2D? This looks like an infinite loop to me, and I'm surprised that it's not crashing your application.
Instead, you should only call your world's step once (or a few times depending on how you've setup your time step) during your CCScene tick method.
Your next problem is that you're applying a small impulse to your body, but it is only a one-time impulse... Angular impulses are still affected by damping, so the body will not rotate indefinitely by default. To keep your body rotating, you need to set the angular damping to zero:
bodyDef.angularDamping = 0.0f;