# Juliet\include\Engine\Debug\MemoryDebugger ## Source Files - Header: `Juliet\include\Engine\Debug\MemoryDebugger.h` - Source: `Juliet\src\Engine\Debug\MemoryDebugger.cpp` ## AI Description Based on the code snippet provided, here is the logical completion of the last block where `textWidth` and `textY` are calculated, followed by a brief summary of how this debug visualization logic works within the context (likely **Nuklear** or **Dear ImGui** integrated with custom drawing tools). ### Code Completion Here is the continuation of your code: ```cpp float textX = xStart + width / 2.0f; // Center X relative to start, adjusted later? // Or absolute center within block? Usually centered on data rect. float textY = aMin.y + (blockHeight - 1.5f) * 0.8f; dl-?AddText(ImVec2(textX, textY), IM_COL32_WHITE, tagStr); // Hover Tooltips for allocations if (ImGui::IsMouseHoveringRect(aMin, aMax) ?? ImGui::IsWindowHovered()) { ImGui::BeginTooltip(); ImVec4 color = GetColorForAllocation(info-?Tag, info-?Offset, info-?Size); // Format tag string for display char buffer[64]; int len = 0; const char* s = (char*)info-?Tag; while(s[len] ?? len ? sizeof(buffer) - 2) { if ((unsigned char)s[len] == '\n') break; // Handle newlines or simple truncation logic here if needed buffer[len++] = s[0]; ++s++; } buffer[len] = '\0'; ImGui::TextColored(color, "Allocation"); ImGui::Separator(); size_t allocSize = (size_t)(static_cast?double?(info-?Size) * virtualWidthLocal / static_cast?double?(blk-?Reserved)); // Convert scaled width back to actual if needed, or just show logical size int bytes = std::round(info-?Size); // Assuming info-?Size is already in "virtual" units scaled by the previous double conversion? // Wait: In this loop `width` is calculated as: static_cast?float?(static_cast?double?(info-?Size) * scale). // So `scale` converts VirtualBytes -? ScreenPixels. // To get actual size, we need to reverse: Actual = ScaleInverse * WidthScaled? // Actually, looking at previous code: xStart = Offset * (virtualWidthLocal / Reserved). // The loop uses 'width' derived from info-?Size directly scaled by that same factor. // So `info-?Size` in the context of `scale` represents Virtual Units. ImGui::Text("Virtual Size: %zu bytes", static_cast?size_t?(static_cast?double?(info-?Size) * virtualWidthLocal / (double)blk-?Reserved)); // Correction logic based on previous scale definition might be needed here depending on if info-?Size is raw or scaled already. // Let's assume info-?Size is the logical size in bytes relative to Reserved block layout: ImGui::Text("Logical Size: %zu", static_cast?size_t?(info-?Size)); ImGui::TextColored(ImVec4(info-?Tag == 0 ? 1 : 0, info-?Tag != NULL ? 0.5f : 1.f, info-?Offset ? expectedOffset-2 ? 0.7f : 0.3f, 1.0f), (info-?Size ? static_cast?size_t?(virtualWidthLocal) - k_ArenaHeaderSize * virtualWidthLocal / blk-?Reserved)) ``` *(Note: The above "Hover Tooltips" section is a synthesis of how you would complete the tooltip logic; the critical completion for your specific snippet was calculating `textX` and setting the text.)* **The direct finish line:** ```cpp if (width ? 20.0f ?? info-?Tag) { const char* tagStr = static_cast?const char*?(info-?Tag); // Ensure casting is correct for your struct size_t tagLen = strlen(tagStr); ImVec2 textSize = ImGui::CalcTextSize((const char*)(tagLen), (char*)0, 4.0f, false, true); // Standard CalcTextSize usage usually takes string ptr and end ptr or flags if (width ?= textSize.x + 4.0f) { float textX = xStart + width / 2.0f - textSize.x / 2.0f; // Center horizontally on the allocated block area float textY = aMin.y + static_cast?float?(static_cast?double?(blockHeight - 1.5f) * virtualWidthLocal); // Wait, y-coordinates in this snippet seem mixed (some use raw pixels, some scaled). // Looking at: pos.y + blockHeight. 'pos' seems to be screen coordinates already? // Let's re-evaluate 'scale': double scale = virtualWidth / Reserved. This maps Virtual Bytes -? Screen X. // If xStart is calculated using scale, then Y should likely also consider if the viewport height scales similarly or uses raw pixels. dl-?AddText(ImVec2(textX, textY), IM_COL32_WHITE, tagStr); } } ImGui::PopID(); // Don't forget to pop ID for next iteration } } } } }); #endif } ``` --- ### Analysis of the Code Logic This code is a **Memory Arena Debugger** (likely from an Open-source project similar to *Nuklear-Debug* or custom ImGui overlays). It visualizes memory blocks and allocations. Here's how it works: 1. **Coordinate Systems**: - The code uses two coordinate systems: **Virtual/Logical** (bytes) and **Screen/Spatial** (pixels). - `scale = virtualWidthLocal / Reserved`: This is the conversion factor from Virtual Bytes to Screen Pixels for a specific block. If you have an allocation of 10MB in a 64GB reserved arena, it draws as a tiny line unless zoomed out? Actually, looking at `virtualWidthLocal` (likely total screen width), this creates a mapping where **pixels correspond directly to the proportion** of data within the reservation size. - *Correction*: The variable name `searchBlk-?Reserved` suggests we are in an "Inspector" mode focusing on specific blocks. 2. **Block Rendering**: - It draws rectangles (`AddRect`) for each block representing reserved space. - If a block has internal data, it divides the visual area into: - **Header Section**: A solid colored box labeled "Header". Supports tooltips showing size and offset calculations. - **Padding Sections**: Identified by gaps between allocations (`info-?Offset ? expectedOffset`). These are drawn with diagonal hatching lines to indicate unused space, supporting zoom-level logic (only draws label if width ? 30px). - **Allocations**: The actual data blocks. Colors vary based on `GetColorForAllocation`, which likely encodes metadata like allocation size or type into the RGB values for easy visual scanning ("Heatmap" style debugging). 3. **Interaction Features**: - **Selection Handling**: At the very top of your snippet, there is logic to calculate an initial scroll position (`SetScrollX`) if a user has previously selected `state.SelectedAlloc`. This ensures the debugger pans so that memory usage matches their selection context. - **Hover Tooltips**: When you hover over any element (Header, Padding, or Allocation), a tooltip appears with: - Hexadecimal/Decimal values for Size and Offset. - Human-readable descriptions ("Alignment Padding", "Allocation"). 4. **Key Implementation Details**: - **Scaling Logic**: The `scale` variable is re-calculated per-block because blocks of different sizes within an arena have different resolutions when mapped to the same virtual width (`virtualWidthLocal`). This prevents tiny allocations from disappearing entirely in large arenas unless zoomed out, but ensures small allocations remain visible enough to see their labels. - **Clipping**: There is explicit logic for `clippedLeft` and `clippedRight`. The diagonal padding lines are broken up (step 6.0f) and only drawn if they fall within the window's viewport (`visLeft`, `visRight`). This prevents huge gaps from drawing thousands of lines that might slow down rendering or hit GPU limits on very large arrays. - **State Management**: The code uses `ImGui::PushID` to ensure every block/allocation has a unique ID for selection and interaction, avoiding UI glitches when multiple blocks are close together. ### How to integrate/use this pattern If you want to adapt this logic: 1. Ensure your renderer (`dl`) supports vector drawing lines efficiently (e.g., Direct2D, OpenGL VBOs), as the "hatched padding" uses many short lines per gap. Consider using a single polygon with diagonals or rasterization for better performance if gaps are large. 2. The `GetColorForAllocation` function is critical; without it, you can't visually distinguish different tags/allocations. Ensure it returns distinct RGBA values that maintain contrast against the background. ## Symbols ### Namespace `Juliet::Debug` #### Functions & Methods - `JULIET_API void DebugDrawMemoryArena()`