我已经编写了一些代码来预先进行3D拾取，但由于某种原因，这些代码无法正常工作！ （我正在使用LWJGL，所以你知道。）
这就是代码的样子：
if(Mouse.getEventButton() == 1) {
if (!Mouse.getEventButtonState()) {
Camera.get().generateViewMatrix();
float screenSpaceX = ((Mouse.getX()/800f/2f)-1.0f)*Camera.get().getAspectRatio();
float screenSpaceY = 1.0f-(2*((600-Mouse.getY())/600f));
float displacementRate = (float)Math.tan(Camera.get().getFovy()/2);
screenSpaceX *= displacementRate;
screenSpaceY *= displacementRate;
Vector4f cameraSpaceNear = new Vector4f((float) (screenSpaceX * Camera.get().getNear()), (float) (screenSpaceY * Camera.get().getNear()), (float) (-Camera.get().getNear()), 1);
Vector4f cameraSpaceFar = new Vector4f((float) (screenSpaceX * Camera.get().getFar()), (float) (screenSpaceY * Camera.get().getFar()), (float) (-Camera.get().getFar()), 1);
Matrix4f tmpView = new Matrix4f();
Camera.get().getViewMatrix().transpose(tmpView);
Matrix4f invertedViewMatrix = (Matrix4f)tmpView.invert();
Vector4f worldSpaceNear = new Vector4f();
Matrix4f.transform(invertedViewMatrix, cameraSpaceNear, worldSpaceNear);
Vector4f worldSpaceFar = new Vector4f();
Matrix4f.transform(invertedViewMatrix, cameraSpaceFar, worldSpaceFar);
Vector3f rayPosition = new Vector3f(worldSpaceNear.x, worldSpaceNear.y, worldSpaceNear.z);
Vector3f rayDirection = new Vector3f(worldSpaceFar.x - worldSpaceNear.x, worldSpaceFar.y - worldSpaceNear.y, worldSpaceFar.z - worldSpaceNear.z);
rayDirection.normalise();
Ray clickRay = new Ray(rayPosition, rayDirection);
Vector tMin = new Vector(), tMax = new Vector(), tempPoint;
float largestEnteringValue, smallestExitingValue, temp, closestEnteringValue = Camera.get().getFar()+0.1f;
Drawable closestDrawableHit = null;
for(Drawable d : this.worldModel.getDrawableThings()) {
// Calcualte AABB for each object... needs to be moved later...
firstVertex = true;
for(Surface surface : d.getSurfaces()) {
for(Vertex v : surface.getVertices()) {
worldPosition.x = (v.x+d.getPosition().x)*d.getScale().x;
worldPosition.y = (v.y+d.getPosition().y)*d.getScale().y;
worldPosition.z = (v.z+d.getPosition().z)*d.getScale().z;
worldPosition = worldPosition.rotate(d.getRotation());
if (firstVertex) {
maxX = worldPosition.x; maxY = worldPosition.y; maxZ = worldPosition.z;
minX = worldPosition.x; minY = worldPosition.y; minZ = worldPosition.z;
firstVertex = false;
} else {
if (worldPosition.x > maxX) {
maxX = worldPosition.x;
}
if (worldPosition.x < minX) {
minX = worldPosition.x;
}
if (worldPosition.y > maxY) {
maxY = worldPosition.y;
}
if (worldPosition.y < minY) {
minY = worldPosition.y;
}
if (worldPosition.z > maxZ) {
maxZ = worldPosition.z;
}
if (worldPosition.z < minZ) {
minZ = worldPosition.z;
}
}
}
}
// ray/slabs intersection test...
// clickRay.getOrigin().x + clickRay.getDirection().x * f = minX
// clickRay.getOrigin().x - minX = -clickRay.getDirection().x * f
// clickRay.getOrigin().x/-clickRay.getDirection().x - minX/-clickRay.getDirection().x = f
// -clickRay.getOrigin().x/clickRay.getDirection().x + minX/clickRay.getDirection().x = f
largestEnteringValue = -clickRay.getOrigin().x/clickRay.getDirection().x + minX/clickRay.getDirection().x;
temp = -clickRay.getOrigin().y/clickRay.getDirection().y + minY/clickRay.getDirection().y;
if(largestEnteringValue < temp) {
largestEnteringValue = temp;
}
temp = -clickRay.getOrigin().z/clickRay.getDirection().z + minZ/clickRay.getDirection().z;
if(largestEnteringValue < temp) {
largestEnteringValue = temp;
}
smallestExitingValue = -clickRay.getOrigin().x/clickRay.getDirection().x + maxX/clickRay.getDirection().x;
temp = -clickRay.getOrigin().y/clickRay.getDirection().y + maxY/clickRay.getDirection().y;
if(smallestExitingValue > temp) {
smallestExitingValue = temp;
}
temp = -clickRay.getOrigin().z/clickRay.getDirection().z + maxZ/clickRay.getDirection().z;
if(smallestExitingValue < temp) {
smallestExitingValue = temp;
}
if(largestEnteringValue > smallestExitingValue) {
//System.out.println("Miss!");
} else {
if (largestEnteringValue < closestEnteringValue) {
closestEnteringValue = largestEnteringValue;
closestDrawableHit = d;
}
}
}
if(closestDrawableHit != null) {
System.out.println("Hit at: (" + clickRay.setDistance(closestEnteringValue).x + ", " + clickRay.getCurrentPosition().y + ", " + clickRay.getCurrentPosition().z);
this.worldModel.removeDrawableThing(closestDrawableHit);
}
}
}
我只是不明白什么是错的，射线是射击而且我确实击中被移除的东西但射线的结果非常奇怪它有时会移除我点击的东西，有时它会移除甚至不能关闭的东西点击即可点击，有时甚至不删除任何内容。
修改
好吧所以我一直在寻找错误并通过调试光线（通过绘制小点所在的地方绘制）我现在可以看到我发出的光线有一些明显的错误......它的起源近在咫尺世界中心，无论我指向相机的哪个位置，总是拍到同一个位置......
我最初的困难是我计算viewMatrix的方式可能有一些错误（因为它不可能从lwjgl中的glulookat方法获取viewmatrix;我必须自己构建它，我猜那就是问题所在在......）
EDIT2：
这就是我目前的计算方法：
private double[][] viewMatrixDouble = {{0,0,0,0}, {0,0,0,0}, {0,0,0,0}, {0,0,0,1}};
public Vector getCameraDirectionVector() {
Vector actualEye = this.getActualEyePosition();
return new Vector(lookAt.x-actualEye.x, lookAt.y-actualEye.y, lookAt.z-actualEye.z);
}
public Vector getActualEyePosition() {
return eye.rotate(this.getRotation());
}
public void generateViewMatrix() {
Vector cameraDirectionVector = getCameraDirectionVector().normalize();
Vector side = Vector.cross(cameraDirectionVector, this.upVector).normalize();
Vector up = Vector.cross(side, cameraDirectionVector);
viewMatrixDouble[0][0] = side.x; viewMatrixDouble[0][1] = up.x; viewMatrixDouble[0][2] = -cameraDirectionVector.x;
viewMatrixDouble[1][0] = side.y; viewMatrixDouble[1][1] = up.y; viewMatrixDouble[1][2] = -cameraDirectionVector.y;
viewMatrixDouble[2][0] = side.z; viewMatrixDouble[2][1] = up.z; viewMatrixDouble[2][2] = -cameraDirectionVector.z;
/*
Vector actualEyePosition = this.getActualEyePosition();
Vector zaxis = new Vector(this.lookAt.x - actualEyePosition.x, this.lookAt.y - actualEyePosition.y, this.lookAt.z - actualEyePosition.z).normalize();
Vector xaxis = Vector.cross(upVector, zaxis).normalize();
Vector yaxis = Vector.cross(zaxis, xaxis);
viewMatrixDouble[0][0] = xaxis.x; viewMatrixDouble[0][1] = yaxis.x; viewMatrixDouble[0][2] = zaxis.x;
viewMatrixDouble[1][0] = xaxis.y; viewMatrixDouble[1][1] = yaxis.y; viewMatrixDouble[1][2] = zaxis.y;
viewMatrixDouble[2][0] = xaxis.z; viewMatrixDouble[2][1] = yaxis.z; viewMatrixDouble[2][2] = zaxis.z;
viewMatrixDouble[3][0] = -Vector.dot(xaxis, actualEyePosition); viewMatrixDouble[3][1] =-Vector.dot(yaxis, actualEyePosition); viewMatrixDouble[3][2] = -Vector.dot(zaxis, actualEyePosition);
*/
viewMatrix = new Matrix4f();
viewMatrix.load(getViewMatrixAsFloatBuffer());
}
如果有人能够验证这是错误的还是正确的，并且是否错误，那将是非常好的。为我提供正确的方法...... 我已经阅读了很多有关此问题的主题和文件，但是我无法接触到我的脑袋......
答案 0 :(得分：0)
我只是不明白什么是错的，射线正在射击，我确实击中了被移除的东西，但是当我按下屏幕时，事情并没有消失。
OpenGL不是场景图，它是一个绘图库。因此，在从内部表示中删除某些内容后，您必须重新绘制场景。并且您的代码缺少对触发重绘的函数的调用。
答案 1 :(得分：0)
好的，所以我终于在gamedev的朋友和朋友的帮助下解决了这个问题，这里是我发布代码的answer的链接！