Calculates the distance of the intersection between the specified ray and the target, or return -1 if the ray doesn't intersect the target - Android java.lang

Android examples for java.lang:Math

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Description

Calculates the distance of the intersection between the specified ray and the target, or return -1 if the ray doesn't intersect the target

Demo Code


//package com.java2s;
import android.opengl.Matrix;

public class Main {
    /**/*from   w w w.j a v a  2s. c o  m*/
     * Calculates the distance of the intersection between the specified ray and the target, or return -1 if the ray
     * doesn't intersect the target
     * 
     * @param rayPoint1
     *            where the ray starts
     * @param rayPoint2
     *            where the ray ends
     * @param target
     *            where is the object to intersect
     * @param precision
     *            the radius to test for intersection
     * @return the distance of intersection
     */
    public static float calculateDistanceOfIntersection(float[] rayPoint1,
            float[] rayPoint2, float[] target, float precision) {
        float raySteps = 100f;
        float objHalfWidth = precision / 2;

        float length = Matrix.length(rayPoint2[0] - rayPoint1[0],
                rayPoint2[1] - rayPoint1[1], rayPoint2[2] - rayPoint1[2]);
        float lengthDiff = length / raySteps;

        float xDif = (rayPoint2[0] - rayPoint1[0]) / raySteps;
        float yDif = (rayPoint2[1] - rayPoint1[1]) / raySteps;
        float zDif = (rayPoint2[2] - rayPoint1[2]) / raySteps;

        for (int i = 0; i < raySteps; i++) {
            // @formatter:off
            if ((rayPoint1[0] + (xDif * i)) > target[0] - objHalfWidth
                    && (rayPoint1[0] + (xDif * i)) < target[0]
                            + objHalfWidth
                    && (rayPoint1[1] + (yDif * i)) > target[1]
                            - objHalfWidth
                    && (rayPoint1[1] + (yDif * i)) < target[1]
                            + objHalfWidth
                    && (rayPoint1[2] + (zDif * i)) > target[2]
                            - objHalfWidth
                    && (rayPoint1[2] + (zDif * i)) < target[2]
                            + objHalfWidth) {
                // @formatter:on
                // Log.v(TouchController.TAG, "HIT: i[" + i + "] wz[" + (rayPoint1[2] + (zDif * i)) + "]");
                // return new Object[] { i * lengthDiff, new float[] { rayPoint1[0] + (xDif * i),
                // rayPoint1[1] + (yDif * i), rayPoint1[2] + (zDif * i) } };
                return i * lengthDiff;
            }
        }
        return -1;
    }
}

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