move TEXTURE_WHITE loading; rm shader.Use() from OnRenderFrame()

Program.cs

@@ -272,6 +272,10 @@ public class Game : GameWindow {
     GL.EnableVertexAttribArray(texCoordLocation);
     GL.VertexAttribPointer(texCoordLocation, 2, VertexAttribPointerType.Float, false, 5 * sizeof(float), 3 * sizeof(float));
 
+    // Load blank white texture.
+    Image<Rgba32> white1x1 = new Image<Rgba32>(1, 1, new Rgba32(255, 255, 255));
+    TEXTURE_WHITE = new Texture(white1x1);
+
     // Load textures from JPEGs.
     string[] files = Directory.GetFiles(@"c:\users\colin\pictures\photos\2023\06\27\");
     textures = new List<Texture>();
@@ -281,11 +285,6 @@ public class Game : GameWindow {
         textures.Add(new Texture(image));
       }
     }
-
-    // Load blank white texture.
-    Image<Rgba32> white1x1 = new Image<Rgba32>(1, 1, new Rgba32(255, 255, 255));
-    TEXTURE_WHITE = new Texture(white1x1);
-    textures.Add(TEXTURE_WHITE);  // FIXME: remove
   }
 
   protected override void OnUnload() {
@@ -309,7 +308,6 @@ public class Game : GameWindow {
     GL.BufferData(BufferTarget.ArrayBuffer, vertices.Length * sizeof(float), vertices, BufferUsageHint.DynamicDraw);
     GL.ActiveTexture(TextureUnit.Texture0);
     GL.BindTexture(TextureTarget.Texture2D, active.Handle);
-    shader.Use();
     GL.DrawElements(PrimitiveType.Triangles, indices.Length, DrawElementsType.UnsignedInt, 0);
 
     for (int i = 0; i < textures.Count; i++) {
@@ -318,7 +316,6 @@ public class Game : GameWindow {
       GL.BufferData(BufferTarget.ArrayBuffer, vertices.Length * sizeof(float), vertices, BufferUsageHint.DynamicDraw);
       GL.ActiveTexture(TextureUnit.Texture0);
       GL.BindTexture(TextureTarget.Texture2D, textures[i].Handle);
-      shader.Use();
       GL.DrawElements(PrimitiveType.Triangles, indices.Length, DrawElementsType.UnsignedInt, 0);
     }