A method typically used for determining what the user selected.

learn more… | top users | synonyms

6
votes
2answers
159 views

How do I convert a 2D movement (from mouse) to a displacement along a 3d axis?

I'm making a small 3D scene editor (that only allow to modify objects positions). Each object is draw with a 3d X/Y/Z axis : How it works : user choose an axis (X, Y or Z) by left clicking on it, ...
6
votes
1answer
144 views

Excluding Background from Color Picking

I've implemented picking based on color coding, but I don't want the background color to be pickable. Is there any way in openGL (2.x) to exclude the background color? For some reason, doing ...
4
votes
2answers
230 views

How do I use D3DXVec3Unproject with D3D11?

I'm having a small issue with D3DXVec3Unproject. I'm currently using Direct3D 11 and not 10, and the signature for this function is: D3DXVECTOR3 *pOut, CONST D3DXVECTOR3 *pV, CONST D3D10_VIEWPORT ...
4
votes
2answers
425 views

Get world coordinate under mouse (at a ground plane for Warcraft 3 like movement)

I want to let a unit follow the mouse like in any RTS (Warcraft 3, Starcraft, ...). For that I have a "ground plane" which is defined through 2 vectors, the X and Z axis. Now I need to get the world ...
4
votes
2answers
828 views

Ray Picking Problems

I've read so many answers on here about how to do Ray Picking, that I thought I had the idea of it down. But when I try to implement it in my game, I get garbage. I'm working with LWJGL. Here's the ...
3
votes
2answers
530 views

Picking 2D objects after transforming camera in XNA

I have an XNA application (a force based visualisation of some circles) that I've implemented zooming and scrolling in, thanks to this guide. Before I had the camera implemented, I had picking ...
3
votes
2answers
4k views

How do you determine which object/surface the user's pointing at with lwjgl?

Title pretty much says it all. I'm working on a simple 'lets get used to lwjgl' project involving manipulation of a rubik's cube, and I can't figure out how to tell which side/square the user's ...
3
votes
1answer
237 views

Best way to Draw a cube for 3D Picking on a specific face

Currently I am drawing a cube for a game that I am making and the cube draw method is below. My question is, what is the best way to draw a cube and to be able to easily find the face that the cursor ...
3
votes
1answer
634 views

Ray picking - get direction from pitch and yaw

I am attempting to cast a ray from the center of the screen and check for collisions with objects. When rendering, I use these calls to set up the camera: GL11.glRotated(mPitch, 1, 0, 0); ...
3
votes
1answer
296 views

3d Picking under reticle

i'm currently trying to work out some 3d picking code that I started years ago, but then lost interested the assignment was completed (this part wasn't actually part of the assignment). I am not ...
3
votes
1answer
113 views

Picking 3D with OpenGL ES 2

I'm trying to implement picking in my framework but I don't understand how I can do this. I'm working with: OpenGL ES 2. GLM mathematic library. What I have understand, picking can be made with ...
3
votes
1answer
836 views

Opengl-es picking object

I saw a lot of picking code opengl-es, but nothing worked. Can someone give me what am I missing? My code is (from tutorials/forums) Vec3 far = Camera.getPosition(); Vec3 near = ...
2
votes
1answer
292 views

OpenGL 3+ Range Picking

How do I perform range picking in the latest OpenGL version? By range picking I mean selecting all objects which are picked using a selection rectangle, like in an RTS game. For single object picking ...
2
votes
1answer
79 views

Triangle Picking Picking Back faces

I'm having a bit of trouble with 3D picking, at first I thought my ray was inaccurate but it turns out that the picking is happening on faces facing the camera and faces facing away from the camera ...
2
votes
1answer
518 views

Triangle accuracy picking for animated models in XNA

I can do picking with triangle-accuracy for non-animated models, but I also have animated models in my game. How do I do picking on animated models? I use code based on this project for animation. ...
2
votes
2answers
211 views

Assigning a different texture based on picking

I'm making a game using XNA. I have some simple objects like cube and sphere, and I would like to change the texture of one face of these objects based on picking. That is, when the cursor is over ...
1
vote
1answer
153 views

Why is texturing interfering with my ID-based picking implementation?

Today I came across a tutorial about color picking and I implemented it on my machine. But there is a problem: when I disable the texture and draw the object I want to pick with its picking color, it ...
1
vote
1answer
2k views

Picking objects with mouse ray

I simply want to pick a few spheres in my scene using the mouse-ray. I have implemented(copied most of it but with little understanding) a ray-sphere collision code. Also I have implemented the code ...
1
vote
1answer
196 views

How to perform efficient 2D picking in HTML5?

I'm currently using an R-Tree for both picking and collision testing. Each entity on screen has a bounding box for collisions and a separate one for picking. Since entities may change position very ...
1
vote
0answers
222 views

2D isometric picking

I'm trying to implement picking in my isometric 2D game, however, I am failing. First of all, I've searched for a solution and came to several, different equations and even a solution using matrices. ...
1
vote
0answers
87 views

Numerically stable(ish) method of getting Y-intercept of mouse position?

I'm trying to unproject the mouse position to get the position on the X-Z plane of a ray cast from the mouse. The camera is fully controllable by the user. Right now, the algorithm I'm using is... ...
1
vote
0answers
436 views

Picking 3D object with Mouse when using Camera Zooming in XNA 4.0

I've tried to figure out how to do picking with the mouse, and things work great when zoomed in all the way with the camera (Third Person Camera). And it works perfectly when using First Person ...
1
vote
0answers
947 views

Controlling 3D model with mouse XNA 4.0 C#

I am creating a 3D table tennis game and the racquet (created in Maya 2012) is controlled by the mouse. I have used picking method to control the racquet, however the cursor is not on the racquet. It ...
0
votes
1answer
244 views

Color Picking Troubles - LWJGL/OpenGL

I'm attempting to check which object the user is hovering over. While everything seems to be just how I'd think it should be, I'm not able to get the correct color due to the second time I draw ...
0
votes
1answer
194 views

Java Slick2d - Mouse picking how to take into account camera

When I move it it obviously changes the viewport so my mouse picking is off. My camera is just a float x and y and I use g.translate(-cam.cameraX+400, -cam.cameraY+300); to translate the graphics. I ...
0
votes
3answers
2k views

3D picking lwjgl

I have written some code to preform 3D picking that for some reason dosn't work entirely correct! (Im using LWJGL just so you know.) I posted this at stackoverflow at first but after researching some ...
0
votes
0answers
60 views

Why would rotating the camera effect my pick ray?

So i'm trying to get terrain picking going. I set up my ray, and I can pick out models, or sprites, whatever I want, no problem. But when I try and get my 3D coords based off terrain collision it ...
0
votes
0answers
102 views

How to create 3d picking ray with the cursor position

I'm new here and I'm not sure how to go about doing this. I am creating an application that is supposed to use the cursor's position in the window to perform 3d picking. The tutorials I have found ...
0
votes
0answers
210 views

Why does RayIntersect return wrong values?

I'm trying to implement Object picking. My BasicModel.cs has a function: public bool CheckRayIntersection(Ray ray) { //Where aabb is the BasicModel's BoundingBox if ...
-1
votes
2answers
508 views

How do I pick correct tile in isometric 3D map?

I want to know how to pick the correct tile on a isometric map in 3D space. Here is a 2D example. They use a colour key map to correctly pick the coordinate. How can I achieve this in 3D space? Is ...
-1
votes
1answer
116 views

Changing map 0,0 origin to top left while using D3DXMatrixOrthoLH

Thanks to Tetrad (for pointing out D3DXMatrixOrthoLH ) I have figured out how to set it up in DirectX9. However, the problem I am now facing is my 0,0 mouse position is now in the middle. What I ...
-2
votes
1answer
203 views

Game Editor - When screen is clicked, how do you identify what coordinate you clicked?

This is a follow-up to my earlier question: Game Editor - When screen is clicked, how do you identify which object that is clicked? Something I've noticed is that picking only calculates a ray and ...
-2
votes
2answers
361 views

Picking a tile in an Iso Engine

I have developed an iso engine for a farm game. In general it works fine, but the problem is that it is not always accurate when pressing the tiles, so the tile I wanted to select is not the one ...
-3
votes
1answer
206 views

Isometric Rendering and Picking [duplicate]

Possible Duplicate: Isometric rendering and picking? I've been looking for a formula to plot (world->screen) and mouse pick (world->screen) isometric tiles in a non-diamond-shaped world. ...