fixed visual bug with guislider

src/main/java/net/minecraftforge/fml/client/config/GuiSlider.java

@@ -20,7 +20,6 @@
 package net.minecraftforge.fml.client.config;
 
 import net.minecraft.client.Minecraft;
-import net.minecraft.client.renderer.GlStateManager;
 
 import javax.annotation.Nullable;
 
@@ -117,9 +116,7 @@ public class GuiSlider extends GuiButtonExt
                 updateSlider();
             }
 
-            GlStateManager.color4f(1.0F, 1.0F, 1.0F, 1.0F);
-            this.drawTexturedModalRect(this.x + (int)(this.sliderValue * (float)(this.width - 8)), this.y, 0, 66, 4, 20);
-            this.drawTexturedModalRect(this.x + (int)(this.sliderValue * (float)(this.width - 8)) + 4, this.y, 196, 66, 4, 20);
+            GuiUtils.drawContinuousTexturedBox(BUTTON_TEXTURES, this.x + (int)(this.sliderValue * (float)(this.width - 8)), this.y, 0, 66, 8, this.height, 200, 20, 2, 3, 2, 2, this.zLevel);
         }
     }