From 5d6bf42397d911ba9002af3c5827a71152368176 Mon Sep 17 00:00:00 2001
From: BZLZHH <admin@bzlzhh.top>
Date: Sat, 21 Jun 2025 02:02:03 +0800
Subject: [PATCH] [Fix] (MG_State/Framebuffer): Correct GL_FRAMEBUFFER target
 handling and resource management.

---
 .../State/Framebuffer/FramebufferState.cpp    | 21 ++++++++++++++++---
 1 file changed, 18 insertions(+), 3 deletions(-)

diff --git a/MG/MG_GL/State/Framebuffer/FramebufferState.cpp b/MG/MG_GL/State/Framebuffer/FramebufferState.cpp
index 1ebc1b99..e296a7a5 100644
--- a/MG/MG_GL/State/Framebuffer/FramebufferState.cpp
+++ b/MG/MG_GL/State/Framebuffer/FramebufferState.cpp
@@ -47,7 +47,6 @@ GLenum FramebufferState::Bind(GLenum target, GLuint framebuffer) {
     if (framebuffer != 0 && !ValidateHandle(framebuffer))
         return GL_INVALID_OPERATION;
     if (target == GL_FRAMEBUFFER) {
-        currentBindings_[GL_FRAMEBUFFER] = framebuffer;
         currentBindings_[GL_READ_FRAMEBUFFER] = framebuffer;
         currentBindings_[GL_DRAW_FRAMEBUFFER] = framebuffer;
     } else {
@@ -61,7 +60,23 @@ GLenum FramebufferState::AttachTexture2D(GLenum target, GLenum attachment,
     if (MG_Constants::Framebuffer::VALID_ATTACHMENTS.find(attachment) == MG_Constants::Framebuffer::VALID_ATTACHMENTS.end() ||
         MG_Constants::Texture::VALID_TARGETS.find(textarget) == MG_Constants::Texture::VALID_TARGETS.end())
         return GL_INVALID_ENUM;
-    // if (target == GL_FRAMEBUFFER) target = GL_DRAW_FRAMEBUFFER;
+    if (target == GL_FRAMEBUFFER) { 
+        if (currentBindings_[GL_READ_FRAMEBUFFER] == currentBindings_[GL_DRAW_FRAMEBUFFER]) {
+            target = GL_DRAW_FRAMEBUFFER;
+        } else {
+            if (currentBindings_[GL_READ_FRAMEBUFFER] != 0) {
+                GLenum err = AttachTexture2D(GL_READ_FRAMEBUFFER, attachment, textarget, texture, level);
+                if (err != GL_NO_ERROR)
+                    return err;
+            }
+            if (currentBindings_[GL_DRAW_FRAMEBUFFER] != 0) {
+                GLenum err = AttachTexture2D(GL_DRAW_FRAMEBUFFER, attachment, textarget, texture, level);
+                if (err != GL_NO_ERROR)
+                    return err;
+            }
+            return GL_NO_ERROR;
+        }
+    }
     FramebufferObject* fbo = GetCurrentFBO(target);
     if (!fbo) return GL_INVALID_OPERATION;
     if (texture != 0 && !MG_State_T::textureState->IsTexture(texture))
@@ -86,7 +101,7 @@ GLenum FramebufferState::AttachTexture2D(GLenum target, GLenum attachment,
 }
 
 GLenum FramebufferState::ValidateCompleteness(GLenum target) {
-    // if (target == GL_FRAMEBUFFER) target = GL_DRAW_FRAMEBUFFER;
+    if (target == GL_FRAMEBUFFER) target = GL_DRAW_FRAMEBUFFER;
     FramebufferObject* fbo = GetCurrentFBO(target);
     if (!fbo) return GL_INVALID_OPERATION;
     return fbo->status;