Ray picking mess - opengl

Question

I am using ray picking to find the boundaries for a character. It's not optimal, but it's the best I can do and will have to do; I need to have (close to) pixelperfect collisions and also I have lots and lots of objects.
I do not however get the raypicking to work correctly. It collides, but not at the right places. I tried adjust the size of the ray, and more to no avail.
Excuse me for the messy code, I just threw it together.
private void renderCollision(Vector3f dir){
//
// Render the models
//
glPushMatrix();
glPushAttrib(GL_ALL_ATTRIB_BITS);
float size = 10.0f;
Picker.startPicking2D(10, 10, 20, 20, -1.0f, size);
//Picker.startPicking2D(10, 10, 20, 20, 0.1f, 20.0f);
glClear (GL_COLOR_BUFFER_BIT);
glDisable(GL_BLEND);
glDisable(GL_ALPHA);
glEnable(GL_DEPTH_TEST);
glDepthFunc(GL_LESS);
glDepthMask(true);
glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
glClearDepth(100.0f);
glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glDisable(GL_TEXTURE_2D);
glLoadIdentity ();
//box.drawMoving(camera);
player.move(dir);
glTranslatef(-player.position.x, -player.position.y + size / 2.0f, -player.position.z);
glRotatef(90.0f, 0.0f, 1.0f, 0.0f);
box.drawAll();
glDisable(GL_DEPTH_TEST);
boolean hit = Picker.getHit();
if (hit) {
player.move(new Vector3f(-dir.x, -dir.y, -dir.z));
}
Picker.stopPicking();
glPopAttrib();
glPopMatrix();
}
public class Picker {
private static IntBuffer selBuffer;
private static int hits;
private static int xSelected;
private static int ySelected;
/**
* Makes the game available for picking (when in 3D mode)
*
* #param xMouse The x coordinate of the mouse on the screen
* #param yMouse The y coordinate of the mouse on the screen
*/
public static void startPicking3D(int xMouse, int yMouse, int screenWidth, int screenHeight, float near, float far) {
startPickingGeneric(xMouse, yMouse);
GLU.gluPerspective(SCREEN_FOV, SCREEN_RAT,
near, far);
GL11.glMatrixMode(GL11.GL_MODELVIEW);
GL11.glLoadIdentity();
}
/**
* Makes the game available for picking (when in 2D mode)
*
* #param xMouse The x coordinate of the mouse on the screen
* #param yMouse The y coordinate of the mouse on the screen
*/
public static void startPicking2D(int xMouse, int yMouse, int screenWidth, int screenHeight, float near, float far) {
startPickingGeneric(xMouse, yMouse);
GL11.glOrtho(0, screenWidth, 0, screenHeight, near, far);
GL11.glMatrixMode(GL11.GL_MODELVIEW);
GL11.glLoadIdentity();
}
/**
* Makes the game available for picking (generic)
*
* #param xMouse The x coordinate of the mouse on the screen
* #param yMouse The y coordinate of the mouse on the screen
*/
private static void startPickingGeneric(int xMouse, int yMouse){
// The selection buffer
selBuffer = ByteBuffer.allocateDirect(1024).order(ByteOrder.nativeOrder()).
asIntBuffer();
IntBuffer vpBuffer = ByteBuffer.allocateDirect(64).
order(ByteOrder.nativeOrder()).asIntBuffer();
// Size of the viewport. [0] Is <x>, [1] Is <y>, [2] Is <width>, [3] Is <height>
int[] viewport = new int[4];
// Get the viewport info
GL11.glGetInteger(GL11.GL_VIEWPORT, vpBuffer);
vpBuffer.get(viewport);
// Set the buffer that OpenGL uses for selection to our buffer
GL11.glSelectBuffer(selBuffer);
// Change to selection mode
GL11.glRenderMode(GL11.GL_SELECT);
// Initialize the name stack (used for identifying which object was selected)
GL11.glInitNames();
GL11.glMatrixMode(GL11.GL_PROJECTION);
GL11.glPushMatrix();
GL11.glLoadIdentity();
// Create 5x5 pixel picking region near cursor location
GLU.gluPickMatrix((float) xMouse, (float) yMouse,
5.0f, 5.0f, IntBuffer.wrap(viewport));
}
/**
* Stops the picking mode
*/
public static void stopPicking(){
GL11.glMatrixMode(GL11.GL_PROJECTION);
GL11.glPopMatrix();
GL11.glMatrixMode(GL11.GL_MODELVIEW);
hits = 0;
hits = GL11.glRenderMode(GL11.GL_RENDER);
}
/**
* Gets the tile the mouse points to
*
* #return TileCoords object with the coordinates of the selected tile
*/
public static boolean getHit(){
int[] buffer = new int[256];
xSelected = -1000;
ySelected = -1000;
selBuffer.get(buffer);
if (hits > 0) {
// If there were more than 0 hits
xSelected = buffer[3]; // Make our selection the first object
ySelected = buffer[4];
int depth = buffer[1]; // Store how far away it is
for (int i = 1; i < hits; i++) {
// Loop through all the detected hits
// If this object is closer to us than the one we have selected
if (buffer[i * 4 + 1] < (int) depth) {
xSelected = buffer[i * 4 + 3]; // Select the closest object
ySelected = buffer[i * 4 + 4];
depth = buffer[i * 4 + 1]; // Store how far away it is
}
}
return true;
}
return false;
}
}

Answer 1

I should rotate around x-axis instead of y-axis and then translate.