From e151bdc34eb1de5e964b9f49e61cc4bb46ff7fd4 Mon Sep 17 00:00:00 2001
From: austin <austin@austinhoover.net>
Date: Mon, 19 May 2025 12:12:36 -0400
Subject: [PATCH] materials read some properties from assimp

---
 assets/Shaders/lib/material.fs                | 16 +-----
 docs/src/progress/renderertodo.md             |  1 +
 .../renderer/model/Material.java              | 55 +++++++++++++++++++
 3 files changed, 59 insertions(+), 13 deletions(-)

diff --git a/assets/Shaders/lib/material.fs b/assets/Shaders/lib/material.fs
index 92ce647a..76679cd6 100644
--- a/assets/Shaders/lib/material.fs
+++ b/assets/Shaders/lib/material.fs
@@ -16,20 +16,10 @@ struct Material {
     /**
       * The shininess value
       */
-    float metallic;
+    float shininess;
 
     /**
-      * The shininess value
+      * The reflectivity value
       */
-    float roughness;
-
-    /**
-      * The shininess value
-      */
-    float ior;
-
-    /**
-      * The shininess value
-      */
-    float alpha;
+    float reflectivity;
 };
diff --git a/docs/src/progress/renderertodo.md b/docs/src/progress/renderertodo.md
index a88b9ae2..ead9531c 100644
--- a/docs/src/progress/renderertodo.md
+++ b/docs/src/progress/renderertodo.md
@@ -1899,6 +1899,7 @@ Shader uniform parsing from source code
 Visual shader uniform location caching
 Remove old uniforms from shaders and code to push uniforms
 Break out shader material into dedicated library file
+Materials read some properties from assimp data
 
 
 
diff --git a/src/main/java/electrosphere/renderer/model/Material.java b/src/main/java/electrosphere/renderer/model/Material.java
index cf3de0f0..6ca5ac66 100644
--- a/src/main/java/electrosphere/renderer/model/Material.java
+++ b/src/main/java/electrosphere/renderer/model/Material.java
@@ -14,8 +14,11 @@ import org.lwjgl.assimp.AIString;
 import org.lwjgl.assimp.AITexture;
 import org.lwjgl.assimp.Assimp;
 import org.lwjgl.opengl.GL45;
+import org.lwjgl.system.MemoryStack;
 
 import java.io.File;
+import java.nio.ByteBuffer;
+import java.nio.FloatBuffer;
 import java.nio.IntBuffer;
 import java.nio.file.Path;
 
@@ -23,6 +26,16 @@ import java.nio.file.Path;
  * A material
  */
 public class Material {
+
+    /**
+     * Default shininess
+     */
+    public static final double DEFAULT_SHININESS = 0.0f;
+
+    /**
+     * The default reflectivity
+     */
+    public static final double DEFAULT_REFLECTIVITY = 0.0f;
     
 
     /**
@@ -55,6 +68,16 @@ public class Material {
      * texture pointer for the normal
      */
     private int normalPointer;
+
+    /**
+     * The shininess value
+     */
+    private double shininess = Material.DEFAULT_SHININESS;
+
+    /**
+     * The reflectivity value
+     */
+    private double reflectivity = Material.DEFAULT_REFLECTIVITY;
     
     /**
      * A material that contains textures
@@ -83,6 +106,11 @@ public class Material {
         AIString aiPathString = AIString.calloc();
 
         //read props
+        try(MemoryStack stack = MemoryStack.stackPush()){
+            //grab specific values
+            rVal.reflectivity = Material.readFloatProp(stack, Assimp.AI_MATKEY_REFLECTIVITY, input, Material.DEFAULT_REFLECTIVITY);
+            rVal.shininess = Material.readFloatProp(stack, Assimp.AI_MATKEY_SHININESS, input, Material.DEFAULT_SHININESS);
+        }
 
         //read textures
         PointerBuffer texturePtrBuff = scene.mTextures();
@@ -270,6 +298,28 @@ public class Material {
         normalPointer = pointer;
         usesFetch = false;
     }
+
+    /**
+     * Reads a float property from a material
+     * @param stack the memory stack
+     * @param key The key for the property
+     * @param input The input material
+     * @param defaultVal The default value
+     * @return The float value
+     */
+    private static float readFloatProp(MemoryStack stack, String key, AIMaterial input, double defaultVal){
+        int numFloats = 1;
+        FloatBuffer buff = stack.callocFloat(numFloats);
+        IntBuffer floatCountBuff = stack.ints(numFloats);
+        ByteBuffer keyBuff = stack.ASCII(key);
+        if(Assimp.aiReturn_SUCCESS == Assimp.aiGetMaterialFloatArray(input, keyBuff, Assimp.aiTextureType_NONE, 0, buff, floatCountBuff)){
+            int numFloatsFound = floatCountBuff.get();
+            if(numFloatsFound > 0){
+                return buff.get();
+            }
+        }
+        return (float)defaultVal;
+    }
     
     /**
      * Applies the material
@@ -299,6 +349,11 @@ public class Material {
             openGLState.glBindTextureUnit(GL45.GL_TEXTURE0, texturePointer, GL45.GL_TEXTURE_2D);
             Globals.renderingEngine.checkError();
         }
+        //send physical properties
+        openGLState.getActiveShader().setUniform(openGLState, "material.shininess", this.shininess);
+        Globals.renderingEngine.checkError();
+        openGLState.getActiveShader().setUniform(openGLState, "material.reflectivity", this.reflectivity);
+        Globals.renderingEngine.checkError();
     }
     
     /**