From 6fe73825d1f72bd0833d1baddd7e64ee7fa74069 Mon Sep 17 00:00:00 2001
From: andy840119 <andy840119@gmail.com>
Date: Sun, 24 Oct 2021 23:46:35 +0800
Subject: [PATCH] apply time moving in the shader.

---
 .../Shaders/CustomizedShaderTestScene.cs      | 20 +++++++++++++++++++
 .../Shaders/RepeatMovingBackgroundShader.cs   | 12 ++++++++++-
 .../Shaders/sh_RepeatMovingBackground.fs      |  7 ++++---
 3 files changed, 35 insertions(+), 4 deletions(-)

diff --git a/osu.Framework.Font.Tests/Visual/Shaders/CustomizedShaderTestScene.cs b/osu.Framework.Font.Tests/Visual/Shaders/CustomizedShaderTestScene.cs
index d1cec3d..35c2bbd 100644
--- a/osu.Framework.Font.Tests/Visual/Shaders/CustomizedShaderTestScene.cs
+++ b/osu.Framework.Font.Tests/Visual/Shaders/CustomizedShaderTestScene.cs
@@ -133,5 +133,25 @@ public void TestRepeatMovingBackgroundShaderBorder(string textureName, float wid
                 };
             });
         }
+
+        [TestCase(0, 0)]
+        [TestCase(1, 1)]
+        [TestCase(0.1f, 0.1f)]
+        [TestCase(5, 2)]
+        public void TestRepeatMovingBackgroundShaderSpeed(float xSpeed, float ySpeed)
+        {
+            AddStep("Apply shader", () =>
+            {
+                ShaderContainer.Shaders = new[]
+                {
+                    GetShaderByType<RepeatMovingBackgroundShader>().With(s =>
+                    {
+                        s.Texture = textures.Get("sample-texture");
+                        s.TextureDisplaySize = new Vector2(30);
+                        s.Speed = new Vector2(xSpeed, ySpeed);
+                    })
+                };
+            });
+        }
     }
 }
diff --git a/osu.Framework.Font/Graphics/Shaders/RepeatMovingBackgroundShader.cs b/osu.Framework.Font/Graphics/Shaders/RepeatMovingBackgroundShader.cs
index b60741b..05f0771 100644
--- a/osu.Framework.Font/Graphics/Shaders/RepeatMovingBackgroundShader.cs
+++ b/osu.Framework.Font/Graphics/Shaders/RepeatMovingBackgroundShader.cs
@@ -8,7 +8,7 @@
 
 namespace osu.Framework.Graphics.Shaders
 {
-    public class RepeatMovingBackgroundShader : InternalShader
+    public class RepeatMovingBackgroundShader : InternalShader, IApplicableToCurrentTime
     {
         public override string ShaderName => "RepeatMovingBackground";
 
@@ -18,6 +18,8 @@ public class RepeatMovingBackgroundShader : InternalShader
 
         public Vector2 TextureDisplayBorder { get; set; }
 
+        public Vector2 Speed { get; set; }
+
         public RepeatMovingBackgroundShader(IShader originShader)
             : base(originShader)
         {
@@ -47,6 +49,14 @@ public override void ApplyValue(FrameBuffer current)
 
             var textureDisplayBorder = TextureDisplayBorder;
             GetUniform<Vector2>("g_DisplayBorder").UpdateValue(ref textureDisplayBorder);
+
+            var speed = Speed;
+            GetUniform<Vector2>("g_Speed").UpdateValue(ref speed);
+        }
+
+        public void ApplyCurrentTime(float currentTime)
+        {
+            GetUniform<float>("g_Time").UpdateValue(ref currentTime);
         }
     }
 }
diff --git a/osu.Framework.Font/Resources/Shaders/sh_RepeatMovingBackground.fs b/osu.Framework.Font/Resources/Shaders/sh_RepeatMovingBackground.fs
index 0fa8c2d..006fc71 100644
--- a/osu.Framework.Font/Resources/Shaders/sh_RepeatMovingBackground.fs
+++ b/osu.Framework.Font/Resources/Shaders/sh_RepeatMovingBackground.fs
@@ -12,15 +12,16 @@ uniform vec2 g_RepeatSampleCoord;
 uniform vec2 g_RepeatSampleSize;
 uniform vec2 g_DisplaySize;
 uniform vec2 g_DisplayBorder;
-uniform vec2 g_Offset;
+uniform vec2 g_Speed;
+uniform float g_Time;
 
 void main(void) {
     // calculate how many times texture should be repeated.
     vec2 repeat = g_TexSize / (g_DisplaySize + g_DisplayBorder);
 
     // get the repeat texture cooldinate.
-    float repeatTexCoordX = mod(v_TexCoord.x * repeat.x + g_Offset.x, 1);
-    float repeatTexCoordY = mod(v_TexCoord.y * repeat.y + g_Offset.y, 1);
+    float repeatTexCoordX = mod(v_TexCoord.x * repeat.x + g_Speed.x * g_Time, 1);
+    float repeatTexCoordY = mod(v_TexCoord.y * repeat.y + g_Speed.y * g_Time, 1);
     vec2 repeatTexCoord = vec2(repeatTexCoordX, repeatTexCoordY) / g_DisplaySize * (g_DisplaySize + g_DisplayBorder);
 
     // because repeat texture will be the size of 1024*1024, so should make a conversion to get the target area of the texture.