Is there a way to find a screen location of a CC3Node? Unity3D has one and it's really convenient. Maybe there already is something like this but I couldn't find it from the source code :(

Hi everyone,

I have a mesh loaded from a pod file and displayed in 3D using cocos3D. I would like to allow the user to rotate this object by sliding his finger on the screen. What I would like to do is to express a rotation in an arbitrary coordinate system where the x and y axis define a plan parallel to the screen of the phone and then transfer this rotation in the coordinate system of the mesh.
Is there a clever way to do this in cocos3D without having to do all the trigonometry myself ?

Have a good day !

Hi all,

Thank you every one for sharing knowledge in creating games - - I've learned a lot from this forum. I could find nearly every answer if I got any problem. However, it looks like no such topic covered yet for how to find the coordinate for a scaled Tiledmap.

Normally, I can use below function to get oordinate,

- (CGPoint)tileCoordForPosition:(CGPoint)position InMap:(CCTMXTiledMap *)map {
int x = position.x / map.tileSize.width;
int y = ((map.mapSize.height * map.tileSize.height) - position.y) / map.tileSize.height;

return ccp(x, y);
}

Could any expert here tell me how to sort it out in a scaled map?

Here I only apply scale in Y axis.

Thanks in advance.

Hello,

Related to this post.

I want to subclass a CCLayer so I can override the visit method with my own openGL code that makes use of a custom camera object.

I am getting seriously confused with how the various coordinate systems are working.

For now, I'll keep everything in PORTRAIT mode, so we avoid confusion.

I'll just write down what I did and hopefully an expert can point out what I did wrong.

- Created a layer, then added an oversized (bigger than 320x480) image as a child. Cocos2D sets the anchor point of this image to the center of it, so I reset it's anchor to 0,0 before adding it as a child.

- When running the scene, I received what I expected. the bottom left of my image was at the bottom left of the screen. Makes sense. i haven't messed with anything yet.

- I added as a member of the layer, a "Camera" object, that basically keeps track of 3 floats - camX, camY, zoom. When initializing this, I set it's X,Y = (0,0) and it's zoom to 1.0 (100%).

- then I overrode the visit method:

-(void)visit{
	CGSize screenDims = [[CCDirector sharedDirector] displaySize]; // autorotation not dealt with here.  You will have to deal with that yourself.
	CGPoint camPos = [[controller gameCam] position];  // MyGameLayer keeps a pointer to its Scene Controller, i.e. [self parent] will also work.
	float camZoom = [[controller gameCam] zoom];
	[[CCDirector sharedDirector] setProjection:kCCDirectorProjectionCustom];
	//now set your projection
	glMatrixMode(GL_PROJECTION);
	//save current projection state
	glPushMatrix();
	glLoadIdentity();
	glOrthof(camPos.x -screenDims.width/(2*camZoom),
			 camPos.x +screenDims.width/(2*camZoom),
			 camPos.y +screenDims.height/(2*camZoom),
			 camPos.y -screenDims.height/(2*camZoom),
			 -1000,
			 1000);
	glMatrixMode(GL_MODELVIEW);

	[super visit];

	//put it back
	glMatrixMode(GL_PROJECTION);
	glPopMatrix();
	glMatrixMode(GL_MODELVIEW);
}

Now, I thought the result of this would be the bottom left corner of my image being located at the centre of the screen, since I wanted to look at 0,0. The result was that the top left corner of the image was displayed at the top left of the screen.

I am totally confused and have no idea what's going on behind the scenes.

I have worked with basic openGL before with C++. Creating viewports, creating and placing cams, etc. I'm probably missing a few key bits of information that give me the whole picture.

Any help would be great! I'm absolutely stuck on this one.

Hello All. I am looking for a better, more gamer friendly way of throwing an object in my game.

I have a horizontally scrolling tilemap.
The player needs to throw an object to hit a target.
Currently, when the player throws the object I have the X and Y ending coord for the thrown object hard coded, so that the thrown object always goes to (player.position.x+100, 150). I use 150 because that is where I have my targets arranged (all at 150 Y).

I want to add other targets at different Y values.

The game is somewhat fast paced (scrolling speed), the player is moved via a joystick and objects are thrown with a button press.

I am looking for a way for the player to select a target prior to throwing.

I am thinking I could use a second "target selection" button, what do you think?

The issue is then, how do I know when a tile with a particular GID is on the screen so that I can set it as a possible target?

Due to animations, sound effects, and a large tilesheet I am already taking a sizable FPS hit, so I need to keep it somewhat simple.

Thanks for any help you can give!

HM50

hello everyone, im newbie to cocos2d for iphone, i studying develop iphone game, but there is problem of UI coordinate confused me, i known the UI's origin point is left top corner, but in convertToUI function, why it assumed the left bottom corner as the origin, when i hold the iphone as OrientatonPortrait.

hello, if i have orthogonal map is easy, but if i have an isometric tilemap how i can get a GID of tile?
the tile is a rhombus not a square :(

How can I get access to information of the CCSprite inside of an array such as x and y positions?
This is my code at the moment and it returns the values of 0 all the time and I don't know why.

for(int i = 0; i < 10; i++)
{
[bulletsBuilder addObject: [CCSprite spriteWithFile:@"bullet.png"]];
}

if(bulletNumber < 10)
{
((CCSprite *)[bulletsBuilder objectAtIndex:bulletNumber]).position = ccp(blob.position.x, blob.position.y);
[self addChild:((CCSprite *)[bulletsBuilder objectAtIndex:bulletNumber])];
NSLog(@"X Position: %i", ((CCSprite *)[bulletsBuilder objectAtIndex:bulletNumber]).position.x); // Returns 0 for some reason
NSLog(@"Y Position: %i", ((CCSprite *)[bulletsBuilder objectAtIndex:bulletNumber]).position.y); // Returns 0 for some reason
bulletNumber++;
}

Thanks.

for(int i = 0; i < 10; i++)
{
[bulletsBuilder addObject: [CCSprite spriteWithFile:@"bullet.png"]];
}

if(bulletNumber < 10)
{
CCSprite *bul = [bulletsBuilder objectAtIndex:bulletNumber];
bul.position = ccp(blob.position.x, blob.position.y);
[self addChild:bul];
bulletNumber++;
}

How do I track certain items in the bulletsBuilder array? I want to check if any of their x positions are larger than say 480.

Is there a better way to create bullet arrays?

Thanks.

Hi,

I want to cycle through texture coordinates like : all pixels of the texture are scrolling via u-coordinate out of the sprite and comming back from the right.
In States with three Pixels named 1, 2 and 3 its like :
<- [123] <- u = 0.0
<- [231] <- u = 0.333
<- [312] <- u = 0.667
<- [123] <- u = 1.0

in CCSprite I added a "setTextureCoordinates" function :
-(void) setTextureCoordinatesBL:(CGPoint)bl BR:(CGPoint)br TL:(CGPoint)tl TR:(CGPoint)tr
{
quad_.bl.texCoords.u = bl.x;
quad_.bl.texCoords.v = bl.y;
quad_.br.texCoords.u = br.x;
quad_.br.texCoords.v = br.y;
quad_.tl.texCoords.u = tl.x;
quad_.tl.texCoords.v = tl.y;
quad_.tr.texCoords.u = tr.x;
quad_.tr.texCoords.v = tr.y;
[selfRenderTextureAtlas_ updateQuad:&quad_ atIndex:0];
}

The Texture is moving as expected but the pixeles are not comming backin from the right side:

<- [123] <- u = 0.0
<- [23 ] <- u = 0.333
<- [3 ] <- u = 0.667
<- [ ] <- u = 1.0

So I guess its because CCSprites loads its texture via GL_CLAMP_TO_EDGE. In my case it should be GL_REPEAT. Where could I say how to load a texture ?

in CCTexture2D I found this :
-(void) setAliasTexParameters
{
ccTexParams texParams = { GL_NEAREST, GL_NEAREST, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE };
[self setTexParameters: &texParams];
}

-(void) setAntiAliasTexParameters
{
ccTexParams texParams = { GL_LINEAR, GL_LINEAR, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE };
[self setTexParameters: &texParams];
}

so it seems that Textures ALWAYS loaded in clamped...

any suggestions?