1.Add black and white filter;

2.Add function: switch filter after swiping the view horizontally or vertically.

Author: winstonwool

app/src/main/java/cn/nekocode/camerafilter/CameraRenderer.java

@@ -35,6 +35,7 @@
 
 import cn.nekocode.camerafilter.filter.AsciiArtFilter;
 import cn.nekocode.camerafilter.filter.BasicDeformFilter;
+import cn.nekocode.camerafilter.filter.BlackAndWhiteFilter;
 import cn.nekocode.camerafilter.filter.BlueorangeFilter;
 import cn.nekocode.camerafilter.filter.CameraFilter;
 import cn.nekocode.camerafilter.filter.ChromaticAberrationFilter;
@@ -163,6 +164,7 @@ public void run() {
         cameraFilterMap.append(R.id.filter18, new CrackedFilter(context));
         cameraFilterMap.append(R.id.filter19, new PolygonizationFilter(context));
         cameraFilterMap.append(R.id.filter20, new JFAVoronoiFilter(context));
+        cameraFilterMap.append(R.id.filter21, new BlackAndWhiteFilter(context));
         setSelectedFilter(selectedFilterId);
 
         // Create texture for camera preview

app/src/main/java/cn/nekocode/camerafilter/MainActivity.java

@@ -23,6 +23,7 @@
 import android.support.v4.app.ActivityCompat;
 import android.support.v4.content.ContextCompat;
 import android.support.v7.app.AppCompatActivity;
+import android.view.GestureDetector;
 import android.view.Menu;
 import android.view.MenuItem;
 import android.view.MotionEvent;
@@ -37,23 +38,45 @@
 import java.io.IOException;
 import java.io.OutputStream;
 import java.text.SimpleDateFormat;
+import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.Date;
 
 /**
  * @author nekocode ([email protected])
  */
-public class MainActivity extends AppCompatActivity {
+public class MainActivity extends AppCompatActivity implements GestureDetector.OnGestureListener {
     private static final int REQUEST_CAMERA_PERMISSION = 101;
     private FrameLayout container;
     private CameraRenderer renderer;
     private TextureView textureView;
     private int filterId = R.id.filter0;
+    private int mCurrentFilterId = 0;
+
+    String[] TITLES = {"Original", "EdgeDectection", "Pixelize",
+            "EMInterference", "TrianglesMosaic", "Legofied",
+            "TileMosaic", "Blueorange", "ChromaticAberration",
+            "BasicDeform", "Contrast", "NoiseWarp", "Refraction",
+            "Mapping", "Crosshatch", "LichtensteinEsque",
+            "AsciiArt", "MoneyFilter", "Cracked", "Polygonization",
+            "JFAVoronoi", "BlackAndWhite"};
+
+    Integer[] FILTER_RES_IDS = {R.id.filter0, R.id.filter1, R.id.filter2, R.id.filter3, R.id.filter4,
+            R.id.filter5, R.id.filter6, R.id.filter7, R.id.filter8, R.id.filter9, R.id.filter10,
+            R.id.filter11, R.id.filter12, R.id.filter13, R.id.filter14, R.id.filter15, R.id.filter16,
+            R.id.filter17, R.id.filter18, R.id.filter19, R.id.filter20,
+            R.id.filter21};
+
+    ArrayList<Integer> mFilterArray = new ArrayList<>(Arrays.asList(FILTER_RES_IDS));
+
+    GestureDetector mGestureDetector;
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(container = new FrameLayout(this));
-        setTitle("Original");
+        setTitle(TITLES[mCurrentFilterId]);
+
 
         if (ContextCompat.checkSelfPermission(this,
                 Manifest.permission.CAMERA)
@@ -71,6 +94,8 @@ protected void onCreate(Bundle savedInstanceState) {
         } else {
             setupCameraPreviewView();
         }
+
+        mGestureDetector = new GestureDetector(this, this);
     }
 
     @Override
@@ -90,20 +115,11 @@ void setupCameraPreviewView() {
         container.addView(textureView);
         textureView.setSurfaceTextureListener(renderer);
 
-        // Show original frame when touch the view
+//        textureView.setOnTouchListener(this);
         textureView.setOnTouchListener(new View.OnTouchListener() {
             @Override
-            public boolean onTouch(View v, MotionEvent event) {
-                switch (event.getAction()) {
-                    case MotionEvent.ACTION_DOWN:
-                        renderer.setSelectedFilter(R.id.filter0);
-                        break;
-
-                    case MotionEvent.ACTION_UP:
-                    case MotionEvent.ACTION_CANCEL:
-                        renderer.setSelectedFilter(filterId);
-                        break;
-                }
+            public boolean onTouch(View view, MotionEvent motionEvent) {
+                mGestureDetector.onTouchEvent(motionEvent);
                 return true;
             }
         });
@@ -139,7 +155,7 @@ public boolean onOptionsItemSelected(MenuItem item) {
 
         if (renderer != null)
             renderer.setSelectedFilter(filterId);
-
+        mCurrentFilterId = mFilterArray.indexOf(filterId);
         return true;
     }
 
@@ -178,4 +194,62 @@ private String genSaveFileName(String prefix, String suffix) {
         String externalPath = Environment.getExternalStorageDirectory().toString();
         return externalPath + "/" + prefix + timeString + suffix;
     }
+
+    @Override
+    public boolean onDown(MotionEvent motionEvent) {
+
+        return false;
+    }
+
+    @Override
+    public void onShowPress(MotionEvent motionEvent) {
+
+    }
+
+    @Override
+    public boolean onSingleTapUp(MotionEvent motionEvent) {
+        return false;
+    }
+
+    @Override
+    public boolean onScroll(MotionEvent motionEvent, MotionEvent motionEvent1, float v, float v1) {
+        return false;
+    }
+
+    @Override
+    public void onLongPress(MotionEvent motionEvent) {
+
+    }
+
+    @Override
+    public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {
+        float velocity = Math.abs(velocityX) > Math.abs(velocityY) ? velocityX : velocityY;
+        int step = velocity > 0 ? -1 : 1;
+        mCurrentFilterId = circleLoop(TITLES.length, mCurrentFilterId, step);
+        setTitle(TITLES[mCurrentFilterId]);
+        if (renderer != null) {
+            renderer.setSelectedFilter(FILTER_RES_IDS[mCurrentFilterId]);
+        }
+        return true;
+    }
+
+    private int circleLoop(int size, int currentPos, int step) {
+        if (step == 0) {
+            return currentPos;
+        }
+
+        if (step > 0) {
+            if (currentPos + step >= size) {
+                return (currentPos + step) % size;
+            } else {
+                return currentPos + step;
+            }
+        } else {
+            if (currentPos + step < 0) {
+                return currentPos + step + size;
+            } else {
+                return currentPos + step;
+            }
+        }
+    }
 }

app/src/main/java/cn/nekocode/camerafilter/filter/BlackAndWhiteFilter.java

@@ -0,0 +1,43 @@
+/*
+ * Copyright 2016 nekocode
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package cn.nekocode.camerafilter.filter;
+
+import android.content.Context;
+import android.opengl.GLES20;
+
+import cn.nekocode.camerafilter.MyGLUtils;
+import cn.nekocode.camerafilter.R;
+
+/**
+ * @author nekocode ([email protected])
+ */
+public class BlackAndWhiteFilter extends CameraFilter {
+    private int program;
+
+    public BlackAndWhiteFilter(Context context) {
+        super(context);
+        program = MyGLUtils.buildProgram(context, R.raw.vertext, R.raw.black_and_white);
+    }
+
+    @Override
+    public void onDraw(int cameraTexId, int canvasWidth, int canvasHeight) {
+        setupShaderInputs(program,
+                new int[]{canvasWidth, canvasHeight},
+                new int[]{cameraTexId},
+                new int[][]{});
+        GLES20.glDrawArrays(GLES20.GL_TRIANGLE_STRIP, 0, 4);
+    }
+}

app/src/main/res/menu/filter.xml

@@ -1,5 +1,5 @@
 <menu xmlns:android="http://schemas.android.com/apk/res/android"
-      xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
     >
 
     <item
@@ -134,4 +134,10 @@
         android:title="JFAVoronoi"
         app:showAsAction="never"
         />
+
+    <item
+        android:id="@+id/filter21"
+        android:title="BlackAndWhite"
+        app:showAsAction="never"
+        />
 </menu>

app/src/main/res/raw/black_and_white.fsh

@@ -0,0 +1,17 @@
+precision highp float;
+
+uniform vec3                iResolution;
+uniform sampler2D           iChannel0;
+varying vec2                texCoord;
+
+void mainImage( out vec4 fragColor, in vec2 fragCoord )
+{
+    vec4 mask = texture2D(iChannel0, fragCoord);
+    float color = (mask.r + mask.g + mask.b) /3.0;
+    vec4 tempColor =vec4(color, color, color,1.0);
+    fragColor = tempColor;
+}
+
+void main() {
+	mainImage(gl_FragColor, texCoord);
+}