Merge pull request #189 from asajeffrey/sharpen-text

Improve reprojection on magicleap

demo/common/src/lib.rs

@@ -25,6 +25,7 @@ use clap::{App, Arg};
 use pathfinder_geometry::basic::vector::{Vector2F, Vector2I};
 use pathfinder_geometry::basic::rect::RectF;
 use pathfinder_geometry::basic::transform2d::Transform2DF;
+use pathfinder_geometry::basic::transform3d::Transform3DF;
 use pathfinder_geometry::color::ColorU;
 use pathfinder_gl::GLDevice;
 use pathfinder_gpu::Device;
@@ -53,6 +54,9 @@ const CAMERA_SCALE_SPEED_2D: f32 = 6.0;
 // How much the scene is scaled when a zoom button is clicked.
 const CAMERA_ZOOM_AMOUNT_2D: f32 = 0.1;
 
+// Half of the eye separation distance.
+const DEFAULT_EYE_OFFSET: f32 = 0.025;
+
 const LIGHT_BG_COLOR: ColorU = ColorU {
     r: 248,
     g: 248,
@@ -323,11 +327,23 @@ impl<W> DemoApp<W> where W: Window {
                 }
                 Event::SetEyeTransforms(new_eye_transforms) => {
                     if let Camera::ThreeD {
+                        ref mut scene_transform,
                         ref mut eye_transforms,
                         ..
                     } = self.camera
                     {
                         *eye_transforms = new_eye_transforms;
+                        // Calculate the new scene transform by lerp'ing the eye transforms.
+                        *scene_transform = eye_transforms[0];
+                        for (index, eye_transform) in eye_transforms.iter().enumerate().skip(1) {
+                            let weight = 1.0 / (index + 1) as f32;
+                            scene_transform.perspective.transform = scene_transform.perspective.transform.lerp(weight, &eye_transform.perspective.transform);
+                            scene_transform.modelview_to_eye = scene_transform.modelview_to_eye.lerp(weight, &eye_transform.modelview_to_eye);
+                         }
+                        // TODO: calculate the eye offset from the eye transforms?
+                        let z_offset = -DEFAULT_EYE_OFFSET * scene_transform.perspective.transform.c0.x();
+                        scene_transform.modelview_to_eye = scene_transform.modelview_to_eye
+                            .pre_mul(&Transform3DF::from_translation(0.0, 0.0, z_offset));
                     }
                 }
                 Event::KeyDown(Keycode::Alphanumeric(b'w')) => {

demo/magicleap/src/main.cpp

@@ -163,19 +163,23 @@ static void onNewInitArg(void* app_handle)
     return;
   }
 
-  if (arg_list_len) {
+  if (!arg_list_len) {
+      return;
+  }
+
   if (MLResult_Ok != MLLifecycleGetInitArgByIndex(arg_list, 0, &arg)) {
     ML_LOG(Error, "%s: Failed to get init arg.", application_name);
-      return;
   }
 
   if (MLResult_Ok != MLLifecycleGetFileInfoListLength(arg, &file_list_len)) {
     ML_LOG(Error, "%s: Failed to get file list length.", application_name);
     return;
   }
+
+  if (!file_list_len) {
+    return;
   }
   
-  if (file_list_len) {
   if (MLResult_Ok != MLLifecycleGetFileInfoByIndex(arg, 0, &file_info)) {
     ML_LOG(Error, "%s: Failed to get file info.", application_name);
     return;
@@ -185,6 +189,10 @@ static void onNewInitArg(void* app_handle)
     ML_LOG(Error, "%s: Failed to get file name.", application_name);
     return;
   }
+
+  if (!file_name) {
+    ML_LOG(Error, "%s: File name is null.", application_name);
+    return;
   }
 
   // Tell pathfinder to load the file
@@ -198,6 +206,7 @@ static void onNewInitArg(void* app_handle)
     return;
   }
 
+  ML_LOG(Info, "%s: Loading %s.", application_name, file_name);
   magicleap_pathfinder_demo_load(app, file_name);
   MLLifecycleFreeInitArgList(&arg_list);
 }

geometry/src/basic/transform3d.rs

@@ -176,6 +176,15 @@ impl Transform3DF {
         )
     }
 
+    /// Linearly interpolate between transforms
+    pub fn lerp(&self, weight: f32, other: &Transform3DF) -> Transform3DF {
+        let c0 = self.c0 * F32x4::splat(weight) + other.c0 * F32x4::splat(1.0 - weight);
+        let c1 = self.c1 * F32x4::splat(weight) + other.c1 * F32x4::splat(1.0 - weight);
+        let c2 = self.c2 * F32x4::splat(weight) + other.c2 * F32x4::splat(1.0 - weight);
+        let c3 = self.c3 * F32x4::splat(weight) + other.c3 * F32x4::splat(1.0 - weight);
+        Transform3DF { c0, c1, c2, c3 }
+    }
+
     /// Just like `gluPerspective()`.
     #[inline]
     pub fn from_perspective(fov_y: f32, aspect: f32, z_near: f32, z_far: f32) -> Transform3DF {