解耦对MessageBox的依赖，提供单独的Shader初始化函数

SpineViewer/MainForm.cs

@@ -12,7 +12,7 @@ using SpineViewer.Exporter;
 
 namespace SpineViewer
 {
-    public partial class MainForm : Form
+    internal partial class MainForm : Form
     {
         private Logger logger = LogManager.GetCurrentClassLogger();
 
@@ -29,6 +29,19 @@ namespace SpineViewer
             toolStripMenuItem_ExportMp4.Tag = ExportType.MP4;
             toolStripMenuItem_ExportMov.Tag = ExportType.MOV;
             toolStripMenuItem_ExportWebm.Tag = ExportType.WebM;
+
+            // 执行一些初始化工作
+            try
+            {
+                Spine.Shader.Init();
+            }
+            catch (Exception ex)
+            {
+                logger.Error(ex.ToString());
+                logger.Error("Failed to load fragment shader");
+                MessageBox.Warn("Fragment shader 加载失败，预乘Alpha通道属性失效");
+            }
+
         }
 
         /// <summary>

SpineViewer/Spine/Implementations/Spine/Spine21.cs

@@ -331,7 +331,7 @@ namespace SpineViewer.Spine.Implementations.Spine
                     if (vertexArray.VertexCount > 0)
                     {
                         if (UsePremultipliedAlpha && (states.BlendMode == BlendModeSFML.Normal || states.BlendMode == BlendModeSFML.Additive))
-                            states.Shader = FragmentShader;
+                            states.Shader = Shader.FragmentShader;
                         else
                             states.Shader = null;
 
@@ -380,7 +380,7 @@ namespace SpineViewer.Spine.Implementations.Spine
             }
 
             if (UsePremultipliedAlpha && (states.BlendMode == BlendModeSFML.Normal || states.BlendMode == BlendModeSFML.Additive))
-                states.Shader = FragmentShader;
+                states.Shader = Shader.FragmentShader;
             else
                 states.Shader = null;
             //clipping.ClipEnd();

SpineViewer/Spine/Implementations/Spine/Spine36.cs

@@ -288,7 +288,7 @@ namespace SpineViewer.Spine.Implementations.Spine
                     if (vertexArray.VertexCount > 0)
                     {
                         if (UsePremultipliedAlpha && (states.BlendMode == BlendModeSFML.Normal || states.BlendMode == BlendModeSFML.Additive))
-                            states.Shader = FragmentShader;
+                            states.Shader = Shader.FragmentShader;
                         else
                             states.Shader = null;
 
@@ -338,7 +338,7 @@ namespace SpineViewer.Spine.Implementations.Spine
             clipping.ClipEnd();
 
             if (UsePremultipliedAlpha && (states.BlendMode == BlendModeSFML.Normal || states.BlendMode == BlendModeSFML.Additive))
-                states.Shader = FragmentShader;
+                states.Shader = Shader.FragmentShader;
             else
                 states.Shader = null;
 

SpineViewer/Spine/Implementations/Spine/Spine37.cs

@@ -262,7 +262,7 @@ namespace SpineViewer.Spine.Implementations.Spine
                     {
                         // XXX: 实测不用设置 sampler2D 的值也正确
                         if (UsePremultipliedAlpha && (states.BlendMode == BlendModeSFML.Normal || states.BlendMode == BlendModeSFML.Additive))
-                            states.Shader = FragmentShader;
+                            states.Shader = Shader.FragmentShader;
                         else
                             states.Shader = null;
 
@@ -312,7 +312,7 @@ namespace SpineViewer.Spine.Implementations.Spine
             clipping.ClipEnd();
 
             if (UsePremultipliedAlpha && (states.BlendMode == BlendModeSFML.Normal || states.BlendMode == BlendModeSFML.Additive))
-                states.Shader = FragmentShader;
+                states.Shader = Shader.FragmentShader;
             else
                 states.Shader = null;
 

SpineViewer/Spine/Implementations/Spine/Spine38.cs

@@ -268,7 +268,7 @@ namespace SpineViewer.Spine.Implementations.Spine
                     {
                         // XXX: 实测不用设置 sampler2D 的值也正确
                         if (UsePremultipliedAlpha && (states.BlendMode == BlendModeSFML.Normal || states.BlendMode == BlendModeSFML.Additive))
-                            states.Shader = FragmentShader;
+                            states.Shader = Shader.FragmentShader;
                         else
                             states.Shader = null;
 
@@ -318,7 +318,7 @@ namespace SpineViewer.Spine.Implementations.Spine
             clipping.ClipEnd();
 
             if (UsePremultipliedAlpha && (states.BlendMode == BlendModeSFML.Normal || states.BlendMode == BlendModeSFML.Additive))
-                states.Shader = FragmentShader;
+                states.Shader = Shader.FragmentShader;
             else
                 states.Shader = null;
 

SpineViewer/Spine/Implementations/Spine/Spine40.cs

@@ -264,7 +264,7 @@ namespace SpineViewer.Spine.Implementations.Spine
                     {
                         // XXX: 实测不用设置 sampler2D 的值也正确
                         if (UsePremultipliedAlpha && (states.BlendMode == BlendModeSFML.Normal || states.BlendMode == BlendModeSFML.Additive))
-                            states.Shader = FragmentShader;
+                            states.Shader = Shader.FragmentShader;
                         else
                             states.Shader = null;
 
@@ -314,7 +314,7 @@ namespace SpineViewer.Spine.Implementations.Spine
             clipping.ClipEnd();
 
             if (UsePremultipliedAlpha && (states.BlendMode == BlendModeSFML.Normal || states.BlendMode == BlendModeSFML.Additive))
-                states.Shader = FragmentShader;
+                states.Shader = Shader.FragmentShader;
             else
                 states.Shader = null;
 

SpineViewer/Spine/Implementations/Spine/Spine41.cs

@@ -264,7 +264,7 @@ namespace SpineViewer.Spine.Implementations.Spine
                     {
                         // XXX: 实测不用设置 sampler2D 的值也正确
                         if (UsePremultipliedAlpha && (states.BlendMode == BlendModeSFML.Normal || states.BlendMode == BlendModeSFML.Additive))
-                            states.Shader = FragmentShader;
+                            states.Shader = Shader.FragmentShader;
                         else
                             states.Shader = null;
 
@@ -314,7 +314,7 @@ namespace SpineViewer.Spine.Implementations.Spine
             clipping.ClipEnd();
 
             if (UsePremultipliedAlpha && (states.BlendMode == BlendModeSFML.Normal || states.BlendMode == BlendModeSFML.Additive))
-                states.Shader = FragmentShader;
+                states.Shader = Shader.FragmentShader;
             else
                 states.Shader = null;
 

SpineViewer/Spine/Implementations/Spine/Spine42.cs

@@ -264,7 +264,7 @@ namespace SpineViewer.Spine.Implementations.Spine
                     {
                         // XXX: 实测不用设置 sampler2D 的值也正确
                         if (UsePremultipliedAlpha && (states.BlendMode == BlendModeSFML.Normal || states.BlendMode == BlendModeSFML.Additive))
-                            states.Shader = FragmentShader;
+                            states.Shader = Shader.FragmentShader;
                         else
                             states.Shader = null;
 
@@ -314,7 +314,7 @@ namespace SpineViewer.Spine.Implementations.Spine
             clipping.ClipEnd();
 
             if (UsePremultipliedAlpha && (states.BlendMode == BlendModeSFML.Normal || states.BlendMode == BlendModeSFML.Additive))
-                states.Shader = FragmentShader;
+                states.Shader = Shader.FragmentShader;
             else
                 states.Shader = null;
 

SpineViewer/Spine/Shader.cs

@@ -0,0 +1,35 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace SpineViewer.Spine
+{
+    public static class Shader
+    {
+        /// <summary>
+        /// 用于解决 PMA 和渐变动画问题的片段着色器
+        /// </summary>
+        private const string FRAGMENT_SHADER = (
+            "uniform sampler2D t;" +
+            "void main() { vec4 p = texture2D(t, gl_TexCoord[0].xy);" +
+            "if (p.a > 0) p.rgb /= max(max(max(p.r, p.g), p.b), p.a);" +
+            "gl_FragColor = gl_Color * p; }"
+        );
+
+        /// <summary>
+        /// 针对预乘 Alpha 通道的片段着色器
+        /// </summary>
+        public static SFML.Graphics.Shader? FragmentShader { get; private set; }
+
+        /// <summary>
+        /// 加载 Shader, 可能会存在异常导致着色器加载失败
+        /// </summary>
+        /// <exception cref="SFML.LoadingFailedException"></exception>
+        public static void Init()
+        {
+            FragmentShader = SFML.Graphics.Shader.FromString(null, null, FRAGMENT_SHADER);
+        }
+    }
+}

SpineViewer/Spine/Spine.cs

@@ -48,41 +48,6 @@ namespace SpineViewer.Spine
         /// </summary>
         public const float SCALE_MIN = 0.001f;
 
-        /// <summary>
-        /// 用于解决 PMA 和渐变动画问题的片段着色器
-        /// </summary>
-        private const string FRAGMENT_SHADER = (
-            "uniform sampler2D t;" +
-            "void main() { vec4 p = texture2D(t, gl_TexCoord[0].xy);" +
-            "if (p.a > 0) p.rgb /= max(max(max(p.r, p.g), p.b), p.a);" +
-            "gl_FragColor = gl_Color * p; }"
-        );
-
-        /// <summary>
-        /// 用于解决 PMA 和渐变动画问题的片段着色器
-        /// </summary>
-        protected static readonly SFML.Graphics.Shader? FragmentShader = null;
-
-        /// <summary>
-        /// 静态构造函数
-        /// </summary>
-        static Spine()
-        {
-            // 加载 FragmentShader
-            try
-            {
-                FragmentShader = SFML.Graphics.Shader.FromString(null, null, FRAGMENT_SHADER);
-            }
-            catch (Exception ex)
-            {
-                FragmentShader = null;
-                var logger = NLog.LogManager.GetCurrentClassLogger();
-                logger.Error(ex.ToString());
-                logger.Error("Failed to load fragment shader");
-                MessageBox.Warn("Fragment shader 加载失败，预乘Alpha通道属性失效"); // TODO: 去除对窗体的调用
-            }
-        }
-
         /// <summary>
         /// 尝试检测骨骼文件版本
         /// </summary>