From 8c19accb007f049c299cdf31eeb8a068d67a1a1a Mon Sep 17 00:00:00 2001
From: Robert Monfera <monfera.robert@gmail.com>
Date: Sat, 5 Nov 2016 15:32:41 +0100
Subject: [PATCH] fix high precision projection

---
 lib/shaders/xform.glsl | 8 ++++----
 package.json           | 2 +-
 scatter-fancy.js       | 4 ++--
 3 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/lib/shaders/xform.glsl b/lib/shaders/xform.glsl
index 9770da4..dbac565 100644
--- a/lib/shaders/xform.glsl
+++ b/lib/shaders/xform.glsl
@@ -1,8 +1,8 @@
 #pragma glslify: export(computePosition)
 vec4 computePosition(vec2 posHi, vec2 posLo, vec2 scHi, vec2 scLo, vec2 trHi, vec2 trLo, vec2 screenScale, vec2 screenOffset) {
-  return vec4(scHi * posHi + trHi
-            + scLo * posHi + trLo
-            + scHi * posLo
-            + scLo * posLo
+  return vec4((posHi + trHi) * scHi
+            + (posLo + trLo) * scHi
+            + (posHi + trHi) * scLo
+            + (posLo + trLo) * scLo
             + screenScale * screenOffset, 0, 1);
 }
\ No newline at end of file
diff --git a/package.json b/package.json
index d847b71..395387f 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "gl-scatter2d-fancy",
-  "version": "1.2.0",
+  "version": "1.2.1",
   "description": "Fancy and slow scatter plots",
   "main": "scatter-fancy.js",
   "scripts": {
diff --git a/scatter-fancy.js b/scatter-fancy.js
index ae2563b..7a96a7e 100644
--- a/scatter-fancy.js
+++ b/scatter-fancy.js
@@ -140,8 +140,8 @@ var proto = GLScatterFancy.prototype
 
     var scaleX = 2 * boundX / dataX
     var scaleY = 2 * boundY / dataY
-    var translateX = 2 * (bounds[0] - dataBox[0]) / dataX - 1
-    var translateY = 2 * (bounds[1] - dataBox[1]) / dataY - 1
+    var translateX = (bounds[0] - dataBox[0] - 0.5 * dataX) / boundX
+    var translateY = (bounds[1] - dataBox[1] - 0.5 * dataY) / boundY
 
     SCALE_HI[0] = scaleX
     SCALE_LO[0] = scaleX - SCALE_HI[0]