Add basic pinch zoom support on Android

Cargo.lock

@@ -280,6 +280,15 @@ dependencies = [
  "cfg-if 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "crossbeam-channel"
+version = "0.3.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "crossbeam-utils 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "smallvec 0.6.9 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "crossbeam-deque"
 version = "0.2.0"
@@ -311,6 +320,15 @@ dependencies = [
  "cfg-if 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "crossbeam-utils"
+version = "0.6.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "cfg-if 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "lazy_static 1.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "deflate"
 version = "0.7.19"
@@ -1029,6 +1047,7 @@ dependencies = [
 name = "pathfinder_magicleap_demo"
 version = "0.1.0"
 dependencies = [
+ "crossbeam-channel 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)",
  "egl 0.2.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "gl 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "glutin 0.19.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1958,9 +1977,11 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum core-foundation-sys 0.6.2 (registry+https://github.com/rust-lang/crates.io-index)" = "e7ca8a5221364ef15ce201e8ed2f609fc312682a8f4e0e3d4aa5879764e0fa3b"
 "checksum core-graphics 0.17.3 (registry+https://github.com/rust-lang/crates.io-index)" = "56790968ab1c8a1202a102e6de05fc6e1ec87da99e4e93e9a7d13efbfc1e95a9"
 "checksum crc32fast 1.1.2 (registry+https://github.com/rust-lang/crates.io-index)" = "e91d5240c6975ef33aeb5f148f35275c25eda8e8a5f95abe421978b05b8bf192"
+"checksum crossbeam-channel 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)" = "0f0ed1a4de2235cabda8558ff5840bffb97fcb64c97827f354a451307df5f72b"
 "checksum crossbeam-deque 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "f739f8c5363aca78cfb059edf753d8f0d36908c348f3d8d1503f03d8b75d9cf3"
 "checksum crossbeam-epoch 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)" = "927121f5407de9956180ff5e936fe3cf4324279280001cd56b669d28ee7e9150"
 "checksum crossbeam-utils 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "2760899e32a1d58d5abb31129f8fae5de75220bc2176e77ff7c627ae45c918d9"
+"checksum crossbeam-utils 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)" = "f8306fcef4a7b563b76b7dd949ca48f52bc1141aa067d2ea09565f3e2652aa5c"
 "checksum deflate 0.7.19 (registry+https://github.com/rust-lang/crates.io-index)" = "8a6abb26e16e8d419b5c78662aa9f82857c2386a073da266840e474d5055ec86"
 "checksum dirs 1.0.5 (registry+https://github.com/rust-lang/crates.io-index)" = "3fd78930633bd1c6e35c4b42b1df7b0cbc6bc191146e512bb3bedf243fcc3901"
 "checksum dlib 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)" = "77e51249a9d823a4cb79e3eca6dcd756153e8ed0157b6c04775d04bf1b13b76a"

demo/android/app/src/main/java/graphics/pathfinder/pathfinderdemo/PathfinderDemoActivity.java

@@ -12,14 +12,15 @@ import android.hardware.SensorEvent;
 import android.hardware.SensorEventListener;
 import android.hardware.SensorManager;
 import android.os.Build;
-import android.provider.Settings;
 import android.support.annotation.NonNull;
 import android.support.annotation.RequiresApi;
 import android.support.v4.app.ActivityCompat;
 import android.support.v4.content.ContextCompat;
 import android.os.Bundle;
 import android.util.Log;
+import android.view.GestureDetector;
 import android.view.MotionEvent;
+import android.view.ScaleGestureDetector;
 import android.view.View;
 
 /**
@@ -35,6 +36,9 @@ public class PathfinderDemoActivity extends Activity {
      */
     private PathfinderDemoSurfaceView mContentView;
 
+    private GestureDetector mGestureDetector;
+    private ScaleGestureDetector mScaleGestureDetector;
+
     ComponentName mVRListenerComponentName;
 
     @Override
@@ -81,20 +85,47 @@ public class PathfinderDemoActivity extends Activity {
         mRenderer = new PathfinderDemoRenderer(this);
         mContentView.setRenderer(mRenderer);
 
+        GestureDetector.SimpleOnGestureListener gestureListener =
+                new GestureDetector.SimpleOnGestureListener() {
+            public boolean onScroll(final MotionEvent from,
+                                    final MotionEvent to,
+                                    final float deltaX,
+                                    final float deltaY) {
+                final int x = Math.round(to.getX());
+                final int y = Math.round(to.getY());
+                PathfinderDemoRenderer.pushMouseDraggedEvent(x, y);
+                return true;
+            }
+
+            public boolean onDown(final MotionEvent event) {
+                final int x = Math.round(event.getX());
+                final int y = Math.round(event.getY());
+                PathfinderDemoRenderer.pushMouseDownEvent(x, y);
+                return true;
+            }
+        };
+        mGestureDetector = new GestureDetector(getApplicationContext(), gestureListener);
+
+        ScaleGestureDetector.SimpleOnScaleGestureListener scaleGestureListener =
+                new ScaleGestureDetector.SimpleOnScaleGestureListener() {
+            public boolean onScale(final ScaleGestureDetector detector) {
+                int focusX = Math.round(detector.getFocusX());
+                int focusY = Math.round(detector.getFocusY());
+                float factor = (detector.getScaleFactor() - 1.0f) * 0.5f;
+                PathfinderDemoRenderer.pushZoomEvent(factor, focusX, focusY);
+                return true;
+            }
+        };
+        mScaleGestureDetector = new ScaleGestureDetector(getApplicationContext(),
+                scaleGestureListener);
+
         mContentView.setOnTouchListener(new View.OnTouchListener() {
             @Override
             public boolean onTouch(final View view, final MotionEvent event) {
-                final int x = Math.round(event.getX());
+                boolean result = mScaleGestureDetector.onTouchEvent(event);
-                final int y = Math.round(event.getY());
+                if (!mScaleGestureDetector.isInProgress())
-                switch (event.getActionMasked()) {
+                    result = mGestureDetector.onTouchEvent(event) || result;
-                    case MotionEvent.ACTION_DOWN:
+                return result;
-                        PathfinderDemoRenderer.pushMouseDownEvent(x, y);
-                        break;
-                    case MotionEvent.ACTION_MOVE:
-                        PathfinderDemoRenderer.pushMouseDraggedEvent(x, y);
-                        break;
-                }
-                return true;
             }
         });
 

demo/android/app/src/main/java/graphics/pathfinder/pathfinderdemo/PathfinderDemoRenderer.java

@@ -22,7 +22,7 @@ public class PathfinderDemoRenderer extends Object implements GvrView.Renderer {
 
     private static native int prepareFrame();
 
-    private static native void drawScene(int sceneIndex);
+    private static native void drawScene();
 
     private static native void finishDrawingFrame();
 
@@ -32,6 +32,8 @@ public class PathfinderDemoRenderer extends Object implements GvrView.Renderer {
 
     public static native void pushMouseDraggedEvent(int x, int y);
 
+    public static native void pushZoomEvent(float scale, int centerX, int centerY);
+
     public static native void pushLookEvent(float pitch, float yaw);
 
     public static native void pushOpenSVGEvent(String path);
@@ -59,8 +61,7 @@ public class PathfinderDemoRenderer extends Object implements GvrView.Renderer {
             }
         }
 
-        for (int sceneIndex = 0; sceneIndex < (inVR ? 2 : 1); sceneIndex++)
+        drawScene();
-            drawScene(sceneIndex);
         finishDrawingFrame();
     }
 

demo/android/rust/src/lib.rs

@@ -84,11 +84,10 @@ pub unsafe extern "system" fn
 pub unsafe extern "system" fn
         Java_graphics_pathfinder_pathfinderdemo_PathfinderDemoRenderer_drawScene(
             env: JNIEnv,
-            class: JClass,
+            class: JClass) {
-            scene_index: i32) {
     DEMO_APP.with(|demo_app| {
         if let Some(ref mut demo_app) = *demo_app.borrow_mut() {
-            demo_app.draw_scene(scene_index as u32)
+            demo_app.draw_scene()
         }
     })
 }
@@ -138,6 +137,17 @@ pub unsafe extern "system" fn
     EVENT_QUEUE.lock().unwrap().push(Event::MouseDragged(Point2DI32::new(x, y)))
 }
 
+#[no_mangle]
+pub unsafe extern "system" fn
+        Java_graphics_pathfinder_pathfinderdemo_PathfinderDemoRenderer_pushZoomEvent(
+            _: JNIEnv,
+            _: JClass,
+            factor: f32,
+            center_x: i32,
+            center_y: i32) {
+    EVENT_QUEUE.lock().unwrap().push(Event::Zoom(factor, Point2DI32::new(center_x, center_y)))
+}
+
 #[no_mangle]
 pub unsafe extern "system" fn
         Java_graphics_pathfinder_pathfinderdemo_PathfinderDemoRenderer_pushLookEvent(
@@ -167,10 +177,6 @@ impl Window for WindowImpl {
         GLVersion::GLES3
     }
 
-    fn mouse_position(&self) -> Point2DI32 {
-        Point2DI32::new(0, 0)
-    }
-
     fn viewport(&self, view: View) -> RectI32 {
         let mut width = self.size.x();
         let mut offset_x = 0;

demo/common/src/lib.rs

@@ -331,10 +331,10 @@ impl<W> DemoApp<W> where W: Window {
                     ui_events.push(UIEvent::MouseDragged(mouse_position));
                     self.dirty = true;
                 }
-                Event::Zoom(d_dist) => {
+                Event::Zoom(d_dist, position) => {
                     if let Camera::TwoD(ref mut transform) = self.camera {
-                        let position = get_mouse_position(&self.window,
+                        let backing_scale_factor = self.window_size.backing_scale_factor;
-                                                          self.window_size.backing_scale_factor);
+                        let position = position.to_f32().scale(backing_scale_factor);
                         *transform = transform.post_translate(-position);
                         let scale_delta = 1.0 + d_dist * CAMERA_SCALE_SPEED_2D;
                         *transform = transform.post_scale(Point2DF32::splat(scale_delta));
@@ -566,7 +566,7 @@ impl<W> DemoApp<W> where W: Window {
         }
 
         self.renderer.debug_ui.ui.mouse_position =
-            get_mouse_position(&self.window, self.window_size.backing_scale_factor);
+            self.last_mouse_position.to_f32().scale(self.window_size.backing_scale_factor);
         self.ui.show_text_effects = self.monochrome_scene_color.is_some();
 
         let mut ui_action = UIAction::None;
@@ -1189,10 +1189,6 @@ fn scale_factor_for_view_box(view_box: RectF32) -> f32 {
     1.0 / f32::min(view_box.size().x(), view_box.size().y())
 }
 
-fn get_mouse_position<W>(window: &W, scale_factor: f32) -> Point2DF32 where W: Window {
-    window.mouse_position().to_f32().scale(scale_factor)
-}
-
 fn get_svg_building_message(built_svg: &BuiltSVG) -> String {
     if built_svg.result_flags.is_empty() {
         return String::new();

demo/common/src/window.rs

@@ -23,7 +23,6 @@ use std::path::PathBuf;
 pub trait Window {
     fn gl_version(&self) -> GLVersion;
     fn gl_default_framebuffer(&self) -> GLuint { 0 }
-    fn mouse_position(&self) -> Point2DI32;
     fn viewport(&self, view: View) -> RectI32;
     fn make_current(&mut self, view: View);
     fn present(&mut self);
@@ -51,7 +50,7 @@ pub enum Event {
     MouseDown(Point2DI32),
     MouseMoved(Point2DI32),
     MouseDragged(Point2DI32),
-    Zoom(f32),
+    Zoom(f32, Point2DI32),
     Look { pitch: f32, yaw: f32 },
     SetEyeTransforms(Vec<OcularTransform>),
     OpenSVG(SVGPath),

demo/native/src/main.rs

@@ -80,11 +80,6 @@ impl Window for WindowImpl {
         GLVersion::GL3
     }
 
-    fn mouse_position(&self) -> Point2DI32 {
-        let mouse_state = self.event_pump.mouse_state();
-        Point2DI32::new(mouse_state.x(), mouse_state.y())
-    }
-
     fn viewport(&self, view: View) -> RectI32 {
         let (width, height) = self.window.drawable_size();
         let mut width = width as i32;
@@ -242,7 +237,11 @@ impl WindowImpl {
             SDLEvent::KeyUp { keycode: Some(sdl_keycode), .. } => {
                 self.convert_sdl_keycode(sdl_keycode).map(Event::KeyUp)
             }
-            SDLEvent::MultiGesture { d_dist, .. } => Some(Event::Zoom(d_dist)),
+            SDLEvent::MultiGesture { d_dist, .. } => {
+                let mouse_state = self.event_pump.mouse_state();
+                let center = Point2DI32::new(mouse_state.x(), mouse_state.y());
+                Some(Event::Zoom(d_dist, center))
+            }
             _ => None,
         }
     }