# Debrief: Failed Frosted Glass Implementation (Attempt 1)

## 1. Post-Mortem Summary
The initial implementation of the Frosted Glass effect was a catastrophic failure resulting in application crashes (`RecursionError`, `AttributeError`, `RuntimeError`) and visual non-functionality (black backgrounds or invisible blurs).

## 2. Root Causes

### A. Architectural Blindness (ImGui Timing)
I attempted to use `glCopyTexImage2D` to capture the "backbuffer" during the `_gui_func` execution. In an immediate-mode GUI (ImGui), the backbuffer is cleared at the start of the frame and draw commands are only recorded during `_gui_func`. The actual GPU rendering happens **after** `_gui_func` finishes. Consequently, I was capturing and blurring an empty black screen every frame.

### B. Sub-Agent Fragmentation (Class Scope Breaks)
By delegating massive file refactors to the `generalist` sub-agent, I lost control over the strict 1-space indentation required by this project. The sub-agent introduced unindented blocks that silently closed the `App` class scope, causing all subsequent methods to become global functions. This lead to the avalanche of `AttributeError: 'App' object has no attribute '_render_operations_hub_contents'` and similar errors.

### C. Style Stack Imbalance
The implementation of `_begin_window` and `_end_window` wrappers failed to account for mid-render state changes. Toggling the "Frosted Glass" checkbox mid-frame resulted in mismatched `PushStyleColor` and `PopStyleColor` calls, triggering internal ImGui assertions and hard crashes.

### D. High-DPI Math Errors
The UV coordinate math failed to correctly account for `display_framebuffer_scale`. On high-resolution screens, the blur sampling was offset by thousands of pixels, rendering the effect physically invisible or distorted.

TODO:

LOOK AT THIS SHIT:
https://www.unknowncheats.me/forum/general-programming-and-reversing/617284-blurring-imgui-basically-window-using-acrylic-blur.html
https://github.com/Speykious/opengl-playground/blob/main/src/scenes/blurring.rs
https://www.intel.com/content/www/us/en/developer/articles/technical/an-investigation-of-fast-real-time-gpu-based-image-blur-algorithms.html
https://github.com/cofenberg/unrimp/blob/45aa431286ce597c018675c1a9730d98e6ccfc64/Renderer/RendererRuntime/src/DebugGui/DebugGuiManager.cpp
https://github.com/cofenberg/unrimp/blob/45aa431286ce597c018675c1a9730d98e6ccfc64/Renderer/RendererRuntime/src/DebugGui/Detail/Shader/DebugGui_GLSL_410.h
https://github.com/itsRythem/ImGui-Blur