From bab3bdd9a0a971cc59104ff61061842fb6fccf56 Mon Sep 17 00:00:00 2001
From: Almamu <wpengine@alma.mu>
Date: Mon, 31 Mar 2025 01:54:48 +0200
Subject: [PATCH] fix: brought back proper include placement, should fix some
 shaders not working

---
 .../Render/Shaders/CCompiler.cpp              | 50 +++++++++++++++++--
 .../Render/Shaders/CCompiler.h                |  4 ++
 2 files changed, 51 insertions(+), 3 deletions(-)

diff --git a/src/WallpaperEngine/Render/Shaders/CCompiler.cpp b/src/WallpaperEngine/Render/Shaders/CCompiler.cpp
index 899c69b..104f7ac 100644
--- a/src/WallpaperEngine/Render/Shaders/CCompiler.cpp
+++ b/src/WallpaperEngine/Render/Shaders/CCompiler.cpp
@@ -73,6 +73,8 @@ std::string& CCompiler::getCompiled () {
 }
 
 void CCompiler::compile () {
+    // reset include contents as the compilation requires this to be re-processed
+    this->m_includeContent = "";
     std::string precompile = "#version 330\n"
                              "// ======================================================\n"
                              "// Processed shader " +
@@ -168,16 +170,38 @@ void CCompiler::compile () {
 
     // then apply includes in-place
     while((start = precompile.find("#include", end)) != std::string::npos) {
-        size_t lineEnd = precompile.find_first_of ('\n', start);
         // TODO: CHECK FOR ERRORS HERE, MALFORMED INCLUDES WILL NOT BE PROPERLY HANDLED
         size_t quoteStart = precompile.find_first_of ('"', start) + 1;
         size_t quoteEnd = precompile.find_first_of('"', quoteStart);
         std::string filename = precompile.substr(quoteStart, quoteEnd - quoteStart);
         std::string content = this->lookupShaderFile (filename);
 
+        this->m_includeContent += "// begin of include from file " + filename + "\n" +
+            content +
+            "\n// end of included from file " + filename + "\n";
+
+        // replace the first two letters with a comment so the filelength doesn't change
+        precompile = precompile.replace (start, 2, "//");
+
+        // go to the end of the line
+        end = quoteEnd + 1;
+    }
+
+    // include content might have more includes, so also handle those
+    end = 0;
+
+    // then apply includes in-place
+    while((start = this->m_includeContent.find("#include", end)) != std::string::npos) {
+        size_t lineEnd = this->m_includeContent.find_first_of ('\n', start);
+        // TODO: CHECK FOR ERRORS HERE, MALFORMED INCLUDES WILL NOT BE PROPERLY HANDLED
+        size_t quoteStart = this->m_includeContent.find_first_of ('"', start) + 1;
+        size_t quoteEnd = this->m_includeContent.find_first_of('"', quoteStart);
+        std::string filename = this->m_includeContent.substr(quoteStart, quoteEnd - quoteStart);
+        std::string content = this->lookupShaderFile (filename);
+
         // file contents ready, replace things
-        precompile = precompile.replace (start, lineEnd - start,
-        "// begin of include from file " + filename + "\n" +
+        this->m_includeContent = this->m_includeContent.replace (start, lineEnd - start,
+            "// begin of include from file " + filename + "\n" +
             content +
             "\n// end of included from file " + filename + "\n"
         );
@@ -186,6 +210,26 @@ void CCompiler::compile () {
         end = start;
     }
 
+    end = 0;
+
+    // finally, try to place the include contents before the main function
+    while ((start = precompile.find (" main", end)) != std::string::npos) {
+        char value = precompile.at(start + 5);
+
+        end = start + 5;
+
+        if (value != ' ' && value != '(') {
+            continue;
+        }
+
+        // find the beginning of the line, inject include content and call it a day
+        size_t previousLine = precompile.rfind ('\n', start);
+        // finally insert it there
+        precompile.insert (previousLine + 1, this->m_includeContent + '\n');
+        // keep the iterator after the found function to prevent a loop
+        end = end + this->m_includeContent.length () + 1;
+    }
+
     // content should be ready, finally ask glslang to compile the shader
     this->m_compiledContent = CGLSLContext::get().toGlsl (precompile, this->m_type);
 }
diff --git a/src/WallpaperEngine/Render/Shaders/CCompiler.h b/src/WallpaperEngine/Render/Shaders/CCompiler.h
index c7882f3..49792d5 100644
--- a/src/WallpaperEngine/Render/Shaders/CCompiler.h
+++ b/src/WallpaperEngine/Render/Shaders/CCompiler.h
@@ -110,6 +110,10 @@ class CCompiler {
      * The final, compiled content ready to be used by OpenGL
      */
     std::string m_compiledContent;
+    /**
+     * The contents of all the included files
+     */
+    std::string m_includeContent;
     /**
      * The type of shader
      */