From a315ecb831c525376e0b60a1c56a68349eaaf1d1 Mon Sep 17 00:00:00 2001
From: WerWolv <werwolv98@gmail.com>
Date: Sun, 17 Dec 2023 18:26:36 +0100
Subject: [PATCH] fix: Flickering of selection frame in hex editor view when
 scrolling

---
 plugins/builtin/include/ui/hex_editor.hpp |  2 +-
 plugins/builtin/source/ui/hex_editor.cpp  | 29 +++++++----------------
 2 files changed, 10 insertions(+), 21 deletions(-)

diff --git a/plugins/builtin/include/ui/hex_editor.hpp b/plugins/builtin/include/ui/hex_editor.hpp
index 02850d657..08341a845 100644
--- a/plugins/builtin/include/ui/hex_editor.hpp
+++ b/plugins/builtin/include/ui/hex_editor.hpp
@@ -26,7 +26,7 @@ namespace hex::plugin::builtin::ui {
         enum class CellType { None, Hex, ASCII };
 
         void drawCell(u64 address, const u8 *data, size_t size, bool hovered, CellType cellType);
-        void drawSelectionFrame(u32 x, u32 y, u64 byteAddress, u16 bytesPerCell, const ImVec2 &cellPos, const ImVec2 &cellSize) const;
+        void drawSelectionFrame(u32 x, u32 y, Region selection, u64 byteAddress, u16 bytesPerCell, const ImVec2 &cellPos, const ImVec2 &cellSize, const ImColor &backgroundColor) const;
         void drawEditor(const ImVec2 &size);
         void drawFooter(const ImVec2 &size);
         void drawTooltip(u64 address, const u8 *data, size_t size) const;
diff --git a/plugins/builtin/source/ui/hex_editor.cpp b/plugins/builtin/source/ui/hex_editor.cpp
index 023173953..32d6f3d73 100644
--- a/plugins/builtin/source/ui/hex_editor.cpp
+++ b/plugins/builtin/source/ui/hex_editor.cpp
@@ -262,10 +262,9 @@ namespace hex::plugin::builtin::ui {
         }
     }
 
-    void HexEditor::drawSelectionFrame(u32 x, u32 y, u64 byteAddress, u16 bytesPerCell, const ImVec2 &cellPos, const ImVec2 &cellSize) const {
+    void HexEditor::drawSelectionFrame(u32 x, u32 y, Region selection, u64 byteAddress, u16 bytesPerCell, const ImVec2 &cellPos, const ImVec2 &cellSize, const ImColor &backgroundColor) const {
         if (!this->isSelectionValid()) return;
 
-        const auto selection = getSelection();
         if (!Region { byteAddress, 1 }.isWithin(selection))
             return;
 
@@ -273,6 +272,9 @@ namespace hex::plugin::builtin::ui {
 
         auto drawList = ImGui::GetWindowDrawList();
 
+        // Draw background color
+        drawList->AddRectFilled(cellPos, cellPos + cellSize, backgroundColor);
+
         // Draw vertical line at the left of first byte and the start of the line
         if (x == 0 || byteAddress == selection.getStartAddress())
             drawList->AddLine(cellPos, cellPos + ImVec2(0, cellSize.y), ImColor(SelectionFrameColor), 1_scaled);
@@ -304,6 +306,8 @@ namespace hex::plugin::builtin::ui {
             return;
         }
 
+        const auto selection = getSelection();
+
         ImGui::PushStyleVar(ImGuiStyleVar_CellPadding, ImVec2(0.5, 0));
         if (ImGui::BeginTable("##hex", byteColumnCount, ImGuiTableFlags_ScrollY | ImGuiTableFlags_SizingFixedFit | ImGuiTableFlags_NoKeepColumnsVisible, size)) {
             View::discardNavigationRequests();
@@ -449,13 +453,8 @@ namespace hex::plugin::builtin::ui {
 
                                 // Draw highlights and selection
                                 if (backgroundColor.has_value()) {
-                                    auto drawList = ImGui::GetWindowDrawList();
-
-                                    // Draw background color
-                                    drawList->AddRectFilled(cellStartPos, cellStartPos + cellSize, backgroundColor.value());
-
                                     // Draw frame around mouse selection
-                                    this->drawSelectionFrame(x, y, byteAddress, bytesPerCell, cellStartPos, cellSize);
+                                    this->drawSelectionFrame(x, y, selection, byteAddress, bytesPerCell, cellStartPos, cellSize, backgroundColor.value());
                                 }
 
                                 const bool cellHovered = ImGui::IsMouseHoveringRect(cellStartPos, cellStartPos + cellSize, false);
@@ -513,12 +512,7 @@ namespace hex::plugin::builtin::ui {
 
                                         // Draw highlights and selection
                                         if (backgroundColor.has_value()) {
-                                            auto drawList = ImGui::GetWindowDrawList();
-
-                                            // Draw background color
-                                            drawList->AddRectFilled(cellStartPos, cellStartPos + cellSize, backgroundColor.value());
-
-                                            this->drawSelectionFrame(x, y, byteAddress, 1, cellStartPos, cellSize);
+                                            this->drawSelectionFrame(x, y, selection, byteAddress, 1, cellStartPos, cellSize, backgroundColor.value());
                                         }
 
                                         ImGui::SetCursorPosX(ImGui::GetCursorPosX() + (this->m_characterCellPadding * 1_scaled) / 2);
@@ -587,12 +581,7 @@ namespace hex::plugin::builtin::ui {
 
                                             // Draw highlights and selection
                                             if (backgroundColor.has_value()) {
-                                                auto drawList = ImGui::GetWindowDrawList();
-
-                                                // Draw background color
-                                                drawList->AddRectFilled(cellStartPos, cellStartPos + cellSize, backgroundColor.value());
-
-                                                this->drawSelectionFrame(x, y, address, 1, cellStartPos, cellSize);
+                                                this->drawSelectionFrame(x, y, selection, address, 1, cellStartPos, cellSize, backgroundColor.value());
                                             }
 
                                             auto startPos = ImGui::GetCursorPos();