From 85992cb492998bfa83e0e6d12d2b37d67df6f2c6 Mon Sep 17 00:00:00 2001
From: glopesdev <glopesdev@users.noreply.github.com>
Date: Thu, 25 Mar 2021 01:41:49 +0000
Subject: [PATCH] Fix gratings rotation pivot and simplify shader

---
 BonVision/Primitives/DrawGratings.bonsai | 77 ++++++++----------------
 BonVision/Shaders/Gratings.frag          |  5 +-
 2 files changed, 27 insertions(+), 55 deletions(-)

diff --git a/BonVision/Primitives/DrawGratings.bonsai b/BonVision/Primitives/DrawGratings.bonsai
index 6920b14..3baa220 100644
--- a/BonVision/Primitives/DrawGratings.bonsai
+++ b/BonVision/Primitives/DrawGratings.bonsai
@@ -1,4 +1,4 @@
-<?xml version="1.0" encoding="utf-8"?>
+<?xml version="1.0" encoding="utf-8"?>
 <WorkflowBuilder Version="2.6.0"
                  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                  xmlns:bv="clr-namespace:BonVision;assembly=BonVision"
@@ -7,6 +7,7 @@
                  xmlns:rx="clr-namespace:Bonsai.Reactive;assembly=Bonsai.Core"
                  xmlns:sys="clr-namespace:System;assembly=mscorlib"
                  xmlns="https://bonsai-rx.org/2018/workflow">
+  <Description>Draws parameterized 2D sinewave gratings.</Description>
   <Workflow>
     <Nodes>
       <Expression xsi:type="WorkflowInput">
@@ -144,6 +145,13 @@
                     <MemberName>X</MemberName>
                     <Value>1</Value>
                   </Expression>
+                  <Expression xsi:type="ExternalizedMapping">
+                    <Property Name="Value" DisplayName="ExtentY" />
+                  </Expression>
+                  <Expression xsi:type="PropertySource" TypeArguments="gl:Scale,sys:Single">
+                    <MemberName>Y</MemberName>
+                    <Value>1</Value>
+                  </Expression>
                   <Expression xsi:type="ExternalizedMapping">
                     <Property Name="Value" DisplayName="Angle" />
                   </Expression>
@@ -164,44 +172,16 @@
                     <Combinator xsi:type="rx:Zip" />
                   </Expression>
                   <Expression xsi:type="scr:ExpressionTransform">
-                    <scr:Expression>single(
-Item1 * Math.Cos(Item3) * Item2
-)</scr:Expression>
+                    <scr:Expression>new(
+single(Item1 * Math.Cos(Item4) * Item3) as Fx,
+single(Item2 * Math.Sin(Item4) * Item3) as Fy)</scr:Expression>
                   </Expression>
-                  <Expression xsi:type="Combinator">
-                    <Combinator xsi:type="gl:UpdateUniform">
-                      <gl:UniformName>frequency_x</gl:UniformName>
-                      <gl:ShaderName>Gratings</gl:ShaderName>
-                    </Combinator>
-                  </Expression>
-                  <Expression xsi:type="ExternalizedMapping">
-                    <Property Name="Value" DisplayName="ExtentY" />
-                  </Expression>
-                  <Expression xsi:type="PropertySource" TypeArguments="gl:Scale,sys:Single">
-                    <MemberName>Y</MemberName>
-                    <Value>1</Value>
-                  </Expression>
-                  <Expression xsi:type="Combinator">
-                    <Combinator xsi:type="FloatProperty">
-                      <Value>10</Value>
-                    </Combinator>
-                  </Expression>
-                  <Expression xsi:type="Combinator">
-                    <Combinator xsi:type="FloatProperty">
-                      <Value>0</Value>
-                    </Combinator>
-                  </Expression>
-                  <Expression xsi:type="Combinator">
-                    <Combinator xsi:type="rx:Zip" />
-                  </Expression>
-                  <Expression xsi:type="scr:ExpressionTransform">
-                    <scr:Expression>single(
-Item1 * Math.Sin(Item3) * Item2
-)</scr:Expression>
+                  <Expression xsi:type="MemberSelector">
+                    <Selector>Fx,Fy</Selector>
                   </Expression>
                   <Expression xsi:type="Combinator">
                     <Combinator xsi:type="gl:UpdateUniform">
-                      <gl:UniformName>frequency_y</gl:UniformName>
+                      <gl:UniformName>frequency</gl:UniformName>
                       <gl:ShaderName>Gratings</gl:ShaderName>
                     </Combinator>
                   </Expression>
@@ -211,26 +191,19 @@ Item1 * Math.Sin(Item3) * Item2
                   <Edge From="0" To="2" Label="Source1" />
                   <Edge From="0" To="4" Label="Source1" />
                   <Edge From="0" To="6" Label="Source1" />
+                  <Edge From="0" To="8" Label="Source1" />
                   <Edge From="1" To="2" Label="Source2" />
-                  <Edge From="2" To="7" Label="Source1" />
+                  <Edge From="2" To="9" Label="Source1" />
                   <Edge From="3" To="4" Label="Source2" />
-                  <Edge From="3" To="13" Label="Source2" />
-                  <Edge From="4" To="7" Label="Source3" />
+                  <Edge From="4" To="9" Label="Source2" />
                   <Edge From="5" To="6" Label="Source2" />
-                  <Edge From="5" To="12" Label="Source2" />
-                  <Edge From="6" To="7" Label="Source2" />
-                  <Edge From="7" To="8" Label="Source1" />
-                  <Edge From="8" To="9" Label="Source1" />
-                  <Edge From="9" To="11" Label="Source1" />
-                  <Edge From="9" To="12" Label="Source1" />
-                  <Edge From="9" To="13" Label="Source1" />
-                  <Edge From="10" To="11" Label="Source2" />
-                  <Edge From="11" To="14" Label="Source1" />
-                  <Edge From="12" To="14" Label="Source2" />
-                  <Edge From="13" To="14" Label="Source3" />
-                  <Edge From="14" To="15" Label="Source1" />
-                  <Edge From="15" To="16" Label="Source1" />
-                  <Edge From="16" To="17" Label="Source1" />
+                  <Edge From="6" To="9" Label="Source4" />
+                  <Edge From="7" To="8" Label="Source2" />
+                  <Edge From="8" To="9" Label="Source3" />
+                  <Edge From="9" To="10" Label="Source1" />
+                  <Edge From="10" To="11" Label="Source1" />
+                  <Edge From="11" To="12" Label="Source1" />
+                  <Edge From="12" To="13" Label="Source1" />
                 </Edges>
               </Workflow>
             </Expression>
diff --git a/BonVision/Shaders/Gratings.frag b/BonVision/Shaders/Gratings.frag
index c7bc151..cf1827e 100644
--- a/BonVision/Shaders/Gratings.frag
+++ b/BonVision/Shaders/Gratings.frag
@@ -1,10 +1,9 @@
 #version 400
 const float pi = 3.1415926535897932384626433832795;
 const float sqrtTwoPi = sqrt(2 * pi);
+uniform vec2 frequency;
 uniform float radius = 1;
 uniform float aperture = 0;
-uniform float frequency_x = 1;
-uniform float frequency_y = 0;
 uniform float contrast = 1;
 uniform float phase = 0;
 uniform float opacity = 1;
@@ -14,7 +13,7 @@ out vec4 fragColor;
 
 void main()
 {
-  float value = texCoord.x * frequency_x + texCoord.y * frequency_y + phase;
+  float value = (texCoord.x - 0.5) * frequency.x + (texCoord.y - 0.5) * frequency.y + phase;
   if (threshold < 0) value = sin(value * 2 * pi); // sinewave
   else value = mod(value, 1) > threshold ? -1 : 1; // square modulation