From 110c7dbfad943217073a05c5a59ad0513658dbee Mon Sep 17 00:00:00 2001
From: Harrison Deng <yunyangdeng@gmail.com>
Date: Fri, 10 Jul 2020 21:55:37 -0500
Subject: [PATCH] Added easy way of switching to nearest filtering.

---
 .../Graphics/Textures/Texture.cs              | 27 ++++++++++++++-----
 .../Loaders/TextureLoader.cs                  |  2 +-
 2 files changed, 22 insertions(+), 7 deletions(-)

diff --git a/src/SlatedGameToolkit.Framework/Graphics/Textures/Texture.cs b/src/SlatedGameToolkit.Framework/Graphics/Textures/Texture.cs
index 6b6fc32..22a0dd5 100644
--- a/src/SlatedGameToolkit.Framework/Graphics/Textures/Texture.cs
+++ b/src/SlatedGameToolkit.Framework/Graphics/Textures/Texture.cs
@@ -27,18 +27,15 @@ namespace SlatedGameToolkit.Framework.Graphics.Textures
         /// </summary>
         /// <param name="textureData">The texture data to use to create the Texture2D.</param>
         /// <param name="context">The openGL context to associate this with. If null, will use the currently active context. Defaults to null.</param>
-        public unsafe Texture(TextureData textureData, GLContext context = null) {
+        public unsafe Texture(TextureData textureData, bool nearest = false, GLContext context = null) {
             this.glContext = context ?? WindowContextsManager.CurrentGL;
             this.width = (uint)textureData.width;
             this.height = (uint)textureData.height;
             uint[] handles = new uint[1];
             glContext.GenTextures(1, handles);
             this.handle = handles[0];
-            Use();
-            glContext.TexParameteri(TextureTarget.Texture2D, TextureParameterName.TextureWrapS, (int)TextureWrapMode.Repeat);
-            glContext.TexParameteri(TextureTarget.Texture2D, TextureParameterName.TextureWrapT, (int)TextureWrapMode.Repeat);
-            glContext.TexParameteri(TextureTarget.Texture2D, TextureParameterName.TextureMinFilter, (int)TextureMinFilter.LinearMipmapLinear);
-            glContext.TexParameteri(TextureTarget.Texture2D, TextureParameterName.TextureMagFilter, (int)TextureMagFilter.Linear);
+
+            SetNearestFilter(nearest);
             fixed(void* p = &textureData.data[0]) {
                 glContext.PixelStorei(PixelStoreParameter.UnpackAlignment, 4);
                 glContext.TexImage2D(TextureTarget.Texture2D, 0, InternalFormat.Rgba, (uint)textureData.width, (uint)textureData.height, 0, PixelFormat.Rgba, PixelType.UnsignedByte, new IntPtr(p));
@@ -46,6 +43,24 @@ namespace SlatedGameToolkit.Framework.Graphics.Textures
             glContext.GenerateMipmap(OpenGL.TextureTarget.Texture2D);
         }
 
+        public void SetNearestFilter(bool nearest = false, bool generateMipMap = false) {
+            Use();
+            if (nearest) {
+                glContext.TexParameteri(TextureTarget.Texture2D, TextureParameterName.TextureWrapS, (int)TextureWrapMode.Repeat);
+                glContext.TexParameteri(TextureTarget.Texture2D, TextureParameterName.TextureWrapT, (int)TextureWrapMode.Repeat);
+                glContext.TexParameteri(TextureTarget.Texture2D, TextureParameterName.TextureMinFilter, (int)TextureMinFilter.NearestMipmapNearest);
+                glContext.TexParameteri(TextureTarget.Texture2D, TextureParameterName.TextureMagFilter, (int)TextureMagFilter.Nearest);
+
+            } else {
+                glContext.TexParameteri(TextureTarget.Texture2D, TextureParameterName.TextureWrapS, (int)TextureWrapMode.Repeat);
+                glContext.TexParameteri(TextureTarget.Texture2D, TextureParameterName.TextureWrapT, (int)TextureWrapMode.Repeat);
+                glContext.TexParameteri(TextureTarget.Texture2D, TextureParameterName.TextureMinFilter, (int)TextureMinFilter.LinearMipmapLinear);
+                glContext.TexParameteri(TextureTarget.Texture2D, TextureParameterName.TextureMagFilter, (int)TextureMagFilter.Linear);
+            }
+            
+            if (!generateMipMap) glContext.GenerateMipmap(OpenGL.TextureTarget.Texture2D);
+        }
+
         public void Use() {
             if (disposed) throw new ObjectDisposedException("Texture");
             glContext.BindTexture(OpenGL.TextureTarget.Texture2D, handle);
diff --git a/src/SlatedGameToolkit.Framework/Loaders/TextureLoader.cs b/src/SlatedGameToolkit.Framework/Loaders/TextureLoader.cs
index 51a63f9..d541a44 100644
--- a/src/SlatedGameToolkit.Framework/Loaders/TextureLoader.cs
+++ b/src/SlatedGameToolkit.Framework/Loaders/TextureLoader.cs
@@ -20,7 +20,7 @@ namespace SlatedGameToolkit.Framework.Loaders
             {
                 ImageResult image = ImageResult.FromStream(stream, ColorComponents.RedGreenBlueAlpha);
                 TextureData textureData = new TextureData(image.Width, image.Height, image.Data);
-                return new Texture(textureData, glContext);
+                return new Texture(textureData, false, glContext);
             }
         }
     }