From b7869646ae203cb129cb6e626643ce3f31080907 Mon Sep 17 00:00:00 2001
From: Linnea Gräf <nea@nea.moe>
Date: Tue, 20 Feb 2024 17:57:18 +0100
Subject: Added shader reload capabilities for chroma resource packs. #958

---
 .../at/hannibal2/skyhanni/utils/shader/Shader.kt   | 95 +++++++++++++++-------
 1 file changed, 64 insertions(+), 31 deletions(-)

diff --git a/src/main/java/at/hannibal2/skyhanni/utils/shader/Shader.kt b/src/main/java/at/hannibal2/skyhanni/utils/shader/Shader.kt
index 6a95655ca..f846c3d4d 100644
--- a/src/main/java/at/hannibal2/skyhanni/utils/shader/Shader.kt
+++ b/src/main/java/at/hannibal2/skyhanni/utils/shader/Shader.kt
@@ -2,11 +2,14 @@ package at.hannibal2.skyhanni.utils.shader
 
 import at.hannibal2.skyhanni.test.command.ErrorManager
 import at.hannibal2.skyhanni.utils.LorenzUtils
-import java.util.function.Supplier
+import net.minecraft.client.Minecraft
+import net.minecraft.client.renderer.OpenGlHelper
+import net.minecraft.client.resources.IReloadableResourceManager
 import net.minecraft.client.shader.ShaderLinkHelper
 import org.apache.commons.lang3.StringUtils
 import org.lwjgl.opengl.GL11
 import org.lwjgl.opengl.OpenGLException
+import java.util.function.Supplier
 
 /**
  * Superclass for shader objects to compile and attach vertex and fragment shaders to the shader program
@@ -15,44 +18,74 @@ import org.lwjgl.opengl.OpenGLException
  *
  * Credit: [Shader.java](https://github.com/BiscuitDevelopment/SkyblockAddons/blob/main/src/main/java/codes/biscuit/skyblockaddons/shader/Shader.java)
  */
-abstract class Shader(vertex: String, fragment: String) {
+abstract class Shader(val vertex: String, val fragment: String) {
+
+    var shaderProgram: Int = -1
+    private var vertexShaderID: Int = -1
+    private var fragmentShaderID: Int = -1
 
-    var shaderProgram: Int = ShaderLinkHelper.getStaticShaderLinkHelper().createProgram()
     private val uniforms: MutableList<Uniform<*>> = mutableListOf()
 
     var created = false
 
     init {
-        run {
-            val vertexShaderID = ShaderManager.loadShader(ShaderType.VERTEX, vertex).also { if (it == -1) return@run }
-            ShaderManager.attachShader(shaderProgram, vertexShaderID)
-
-            val fragmentShaderID = ShaderManager.loadShader(ShaderType.FRAGMENT, fragment).also { if (it == -1) return@run }
-            ShaderManager.attachShader(shaderProgram, fragmentShaderID)
-
-            ShaderHelper.glLinkProgram(shaderProgram)
-
-            if (ShaderHelper.glGetProgrami(shaderProgram, ShaderHelper.GL_LINK_STATUS) == GL11.GL_FALSE) {
-                val errorMessage = "Failed to link vertex shader $vertex and fragment shader $fragment. Features that " +
-                        "utilise this shader will not work correctly, if at all."
-                val errorLog = StringUtils.trim(ShaderHelper.glGetShaderInfoLog(shaderProgram, 1024))
-
-                if (ShaderManager.inWorld()) {
-                    ErrorManager.logErrorWithData(
-                            OpenGLException("Shader linking error."),
-                            errorMessage,
-                            "Link Error:\n" to errorLog
-                    )
-                } else {
-                    LorenzUtils.consoleLog("$errorMessage $errorLog")
-                }
-
-                return@run
-            }
+        recompile()
+        (Minecraft.getMinecraft().resourceManager as IReloadableResourceManager).registerReloadListener {
+            recompile()
+        }
+    }
 
-            this.registerUniforms()
-            created = true
+    fun deleteOldShaders() {
+        if (vertexShaderID >= 0) {
+            OpenGlHelper.glDeleteShader(vertexShaderID)
+            vertexShaderID = -1
+        }
+        if (fragmentShaderID >= 0) {
+            OpenGlHelper.glDeleteShader(fragmentShaderID)
+            fragmentShaderID = -1
         }
+        if (shaderProgram >= 0) {
+            OpenGlHelper.glDeleteProgram(shaderProgram)
+            shaderProgram = -1
+        }
+        uniforms.clear()
+        created = false
+    }
+
+    fun recompile() {
+        deleteOldShaders()
+        shaderProgram = ShaderLinkHelper.getStaticShaderLinkHelper().createProgram()
+        if (shaderProgram < 0) return
+
+        vertexShaderID = ShaderManager.loadShader(ShaderType.VERTEX, vertex)
+        if (vertexShaderID < 0) return
+        ShaderManager.attachShader(shaderProgram, vertexShaderID)
+
+        fragmentShaderID = ShaderManager.loadShader(ShaderType.FRAGMENT, fragment)
+        if (fragmentShaderID < 0) return
+        ShaderManager.attachShader(shaderProgram, fragmentShaderID)
+
+        ShaderHelper.glLinkProgram(shaderProgram)
+
+        if (ShaderHelper.glGetProgrami(shaderProgram, ShaderHelper.GL_LINK_STATUS) == GL11.GL_FALSE) {
+            val errorMessage = "Failed to link vertex shader $vertex and fragment shader $fragment. Features that " +
+                "utilise this shader will not work correctly, if at all."
+            val errorLog = StringUtils.trim(ShaderHelper.glGetShaderInfoLog(shaderProgram, 1024))
+
+            if (ShaderManager.inWorld()) {
+                ErrorManager.logErrorWithData(
+                    OpenGLException("Shader linking error."),
+                    errorMessage,
+                    "Link Error:\n" to errorLog
+                )
+            } else {
+                LorenzUtils.consoleLog("$errorMessage $errorLog")
+            }
+            return
+        }
+
+        this.registerUniforms()
+        created = true
     }
 
     abstract fun registerUniforms()
-- 
cgit