From 36441691765791d12d0667c643dd9a54146f6a6b Mon Sep 17 00:00:00 2001
From: Stewart Allen <so@a3z.co>
Date: Sun, 16 Oct 2022 23:20:09 -0400
Subject: [PATCH] mobile pinch zoom and layer slider improvements

---
 release.md          |  1 +
 src/moto/orbit.js   | 31 ++++++++++++++-----------------
 src/moto/space.js   |  7 +++++--
 web/kiri/index.html |  1 +
 4 files changed, 21 insertions(+), 19 deletions(-)

diff --git a/release.md b/release.md
index 0b923c02..e99ecc67 100644
--- a/release.md
+++ b/release.md
@@ -5,6 +5,7 @@ Full docs @ https://docs.grid.space/projects/kiri-moto
 
 # Release 3.6
 
+* mobile pinch zoom and layer slider improvements
 * update CLI to work in CAM mode and add working samples
 * improved FDM preview rendering speed and reduced memory usage
 * threaded task and message passing performance improvements
diff --git a/src/moto/orbit.js b/src/moto/orbit.js
index b0ad3a72..24e0f8dc 100644
--- a/src/moto/orbit.js
+++ b/src/moto/orbit.js
@@ -234,18 +234,14 @@ moto.Orbit = function (object, domElement, notify, slider) {
         return pos;
     };
 
-    this.dollyIn = function (dollyScale) {
-        if (dollyScale === undefined) {
-            dollyScale = getZoomScale();
-        }
-        scale *= dollyScale;
+    this.dollyIn = function (factor = 1) {
+        let dollyScale = getZoomScale(factor);
+        scale = scale * dollyScale;
     };
 
-    this.dollyOut = function (dollyScale) {
-        if (dollyScale === undefined) {
-            dollyScale = getZoomScale();
-        }
-        scale /= dollyScale;
+    this.dollyOut = function (factor = 1) {
+        let dollyScale = getZoomScale(factor);
+        scale = scale / dollyScale;
     };
 
     this.update = function () {
@@ -338,8 +334,8 @@ moto.Orbit = function (object, domElement, notify, slider) {
         return theta
     };
 
-    function getZoomScale() {
-        return Math.pow(0.95, scope.zoomSpeed);
+    function getZoomScale(factor = 1) {
+        return Math.pow(0.95, factor * scope.zoomSpeed);
     }
 
     function onMouseDown(event) {
@@ -561,6 +557,7 @@ moto.Orbit = function (object, domElement, notify, slider) {
             case 2: // two-fingered touch: dolly
                 if (scope.noZoom === true) return;
                 if (state !== STATE.TOUCH_DOLLY) return;
+
                 let dx = event.touches[ 0 ].pageX - event.touches[ 1 ].pageX;
                 let dy = event.touches[ 0 ].pageY - event.touches[ 1 ].pageY;
                 let distance = Math.sqrt(dx * dx + dy * dy);
@@ -574,15 +571,15 @@ moto.Orbit = function (object, domElement, notify, slider) {
                 dollyEnd.set(0, distance);
                 dollyDelta.subVectors(dollyEnd, dollyStart);
 
-                if (touchSlide || (Math.abs(ddy/ddx) > 10 && slider)) {
+                if (touchSlide || (Math.abs(dy/dx) < 1 && slider)) {
                     touchSlide = true;
-                    slider(lastDY ? lastDY - ddy : ddy);
+                    slider(lastDY ? (lastDY - ddy) : ddy);
                     lastDY = ddy;
                 } else {
                     if (dollyDelta.y > 0) {
-                        scope.dollyOut();
-                    } else {
-                        scope.dollyIn();
+                        scope.dollyOut(0.5);
+                    } else if (dollyDelta.y < 0) {
+                        scope.dollyIn(0.5);
                     }
                 }
 
diff --git a/src/moto/space.js b/src/moto/space.js
index 603d6200..8b01f7a7 100644
--- a/src/moto/space.js
+++ b/src/moto/space.js
@@ -1316,8 +1316,11 @@ gapp.register("moto.space", [], (root, exports) => {
             domelement.style.height = height();
 
             // workaround for https://bugs.chromium.org/p/chromium/issues/detail?id=1321452
-            let Renderer = nav.platform === 'MacIntel' &&
-                nav.vendor.indexOf('Google') >= 0 ? WebGL1Renderer : WebGLRenderer;
+            // and android requires older rendered to avoid visual Z order artifacts
+            let Renderer =
+                (nav.platform.indexOf('Linux') >= 0) ||
+                (nav.platform === 'MacIntel' && nav.vendor.indexOf('Google') >= 0) ?
+                WebGL1Renderer : WebGLRenderer;
 
             renderer = new Renderer({
                 antialias: antiAlias,
diff --git a/web/kiri/index.html b/web/kiri/index.html
index c01a1a3c..5b8b7d50 100644
--- a/web/kiri/index.html
+++ b/web/kiri/index.html
@@ -15,6 +15,7 @@
     <meta name="apple-mobile-web-app-capable" content="yes">
     <meta name="apple-mobile-web-app-status-bar-style" content="black-translucent">
     <meta http-equiv="origin-trial" content="AhKwa7D89KrdZmlwXxZAHsVTBkm6+44cKZH6X9d37NhZ4UbkDllzmctGSMTSS+Xx51MPFoRf4maqlXXDqefcCg8AAAB0eyJvcmlnaW4iOiJodHRwczovL2dyaWQuc3BhY2U6NDQzIiwiZmVhdHVyZSI6IlVucmVzdHJpY3RlZFNoYXJlZEFycmF5QnVmZmVyIiwiZXhwaXJ5IjoxNjc1Mjk1OTk5LCJpc1N1YmRvbWFpbiI6dHJ1ZX0=">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no">
     <title>Kiri:Moto</title>
     <link rel="icon" href="/kiri/favicon.ico">
     <link rel="apple-touch-icon" href="/kiri/favicon-mobile.png">