update lib in view Graph

demoProjects/ViewsGraph3d/app/src/main/java/android/support/constraintLayout/extlib/graph3d/Object3D.java

@@ -22,7 +22,9 @@
 public class Object3D {
     protected float[] vert;
     protected float[] normal;
-    protected int[] index;
+
+    protected short[] index;
+
     protected float[] tVert; // the vertices transformed into screen space
     protected float mMinX, mMaxX, mMinY, mMaxY, mMinZ, mMaxZ; // bounds in x,y & z
     protected int mType = 4;
@@ -46,7 +48,7 @@ public void makeVert(int n) {
     }
 
     public void makeIndexes(int n) {
-        index = new int[n * 3];
+        index = new short[n * 3];
     }
 
     public void transform(Matrix m) {

demoProjects/ViewsGraph3d/app/src/main/java/android/support/constraintLayout/extlib/graph3d/ViewMatrix.java

@@ -77,6 +77,19 @@ public void setLookPoint(double[] mLookPoint) {
         this.mLookPoint = mLookPoint;
     }
 
+    /**
+     * return the distance from the look point to the eye point
+     * @return
+     */
+    public double calCameraDistance() {
+        double[] zv = {
+                mEyePoint[0] - mLookPoint[0],
+                mEyePoint[1] - mLookPoint[1],
+                mEyePoint[2] - mLookPoint[2]
+        };
+        return  VectorUtil.norm(zv);
+    }
+
     public double[] getEyePoint() {
         return mEyePoint;
     }
@@ -271,13 +284,15 @@ public void lookAt(Object3D tri, float[] voxelDim, int w, int h) {
     double[] mMoveToV = new double[3];
     double[] mStartEyePoint;
     double[] mStartUpVector;
+    double dist = 0;
     Quaternion mQ = new Quaternion(0, 0, 0, 0);
 
     public void trackBallUP(float x, float y) {
 
     }
 
     public void trackBallDown(float x, float y) {
+        dist = calCameraDistance();
         mStartx = x;
         mStarty = y;
         ballToVec(x, y, mStartV);
@@ -304,7 +319,8 @@ public void trackBallMove(float x, float y) {
 
         mEyePoint = mQ.rotateVec(mEyePoint);
         mUpVector = mQ.rotateVec(mStartUpVector);
-
+        VectorUtil.normalize(mEyePoint);
+        VectorUtil.mult(mEyePoint,dist,mEyePoint);
         VectorUtil.sub(mLookPoint, mEyePoint, mEyePoint);
         calcMatrix();
 

demoProjects/ViewsGraph3d/app/src/main/java/android/support/constraintLayout/extlib/graph3d/objects/AxisBox.java

@@ -48,18 +48,19 @@ void buildBox() {
             vert[i * 3 + 2] = (((i >> 2) & 1) == 0) ? mMinZ : mMaxZ; // Z
         }
 
-        index = new int[6 * 2* 3]; // 6 sides x 2 triangles x 3 points per triangle
-        int []sides = {  // pattern of clockwise triangles around cube
+
+        index = new short[6 * 2 * 3]; // 6 sides x 2 triangles x 3 points per triangle
+        short []sides = {  // pattern of clockwise triangles around cube
                 0, 2, 1, 3, 1, 2,
                 0, 1, 4, 5, 4, 1,
                 0, 4, 2, 6, 2, 4,
                 7, 6, 5, 4, 5, 6,
                 7, 3, 6, 2, 6, 3,
                 7, 5, 3, 1, 3, 5
         };
-        index = new int[sides.length];
+        index = new short[sides.length];
         for (int i = 0; i < sides.length; i++) {
-            index[i] = sides[i]*3;
+            index[i] = (short) (3*sides[i]);
         }
     }
 

demoProjects/ViewsGraph3d/app/src/main/java/android/support/constraintLayout/extlib/graph3d/objects/Surface3D.java

@@ -139,13 +139,14 @@ public void calcSurface(float t, boolean resetZ) {
                 int p2 = 3 * (1 + ix + iy * (mSize + 1));
                 int p3 = 3 * (ix + (iy + 1) * (mSize + 1));
                 int p4 = 3 * (1 + ix + (iy + 1) * (mSize + 1));
-                index[count++] = p1;
-                index[count++] = p2;
-                index[count++] = p3;
+                index[count++] = (short)p1;
+                index[count++] = (short)p2;
+                index[count++] = (short)p3;
+
+                index[count++] = (short)p4;
+                index[count++] = (short)p3;
+                index[count++] = (short)p2;
 
-                index[count++] = p4;
-                index[count++] = p3;
-                index[count++] = p2;
             }
         }
     }