From d003674f2cc3a653ca61a6d4d3cc35a95fc83e1e Mon Sep 17 00:00:00 2001 From: omar Date: Thu, 7 Nov 2019 16:05:03 +0100 Subject: [PATCH] Internals: Added ImChunkStream, used by window settings. (more generic followup to 4c13807, the class will be used more extensively by Tables) --- imgui.cpp | 36 +++++++++++++++++++----------------- imgui_internal.h | 42 ++++++++++++++++++++++++++++++++---------- 2 files changed, 51 insertions(+), 27 deletions(-) diff --git a/imgui.cpp b/imgui.cpp index c75eb179..c15121a3 100644 --- a/imgui.cpp +++ b/imgui.cpp @@ -2525,7 +2525,7 @@ ImGuiWindow::ImGuiWindow(ImGuiContext* context, const char* name) LastTimeActive = -1.0f; ItemWidthDefault = 0.0f; FontWindowScale = 1.0f; - SettingsIdx = -1; + SettingsOffset = -1; DrawList = &DrawListInst; DrawList->_OwnerName = Name; @@ -3818,7 +3818,6 @@ void ImGui::Shutdown(ImGuiContext* context) g.PrivateClipboard.clear(); g.InputTextState.ClearFreeMemory(); - g.SettingsWindowsNames.clear(); g.SettingsWindows.clear(); g.SettingsHandlers.clear(); @@ -4704,7 +4703,7 @@ static ImGuiWindow* CreateNewWindow(const char* name, ImVec2 size, ImGuiWindowFl if (ImGuiWindowSettings* settings = ImGui::FindWindowSettings(window->ID)) { // Retrieve settings from .ini file - window->SettingsIdx = g.SettingsWindows.index_from_ptr(settings); + window->SettingsOffset = g.SettingsWindows.offset_from_ptr(settings); SetWindowConditionAllowFlags(window, ImGuiCond_FirstUseEver, false); window->Pos = ImVec2(settings->Pos.x, settings->Pos.y); window->Collapsed = settings->Collapsed; @@ -9205,27 +9204,31 @@ void ImGui::MarkIniSettingsDirty(ImGuiWindow* window) ImGuiWindowSettings* ImGui::CreateNewWindowSettings(const char* name) { ImGuiContext& g = *GImGui; - g.SettingsWindows.push_back(ImGuiWindowSettings()); - ImGuiWindowSettings* settings = &g.SettingsWindows.back(); + #if !IMGUI_DEBUG_INI_SETTINGS // Skip to the "###" marker if any. We don't skip past to match the behavior of GetID() // Preserve the full string when IMGUI_DEBUG_INI_SETTINGS is set to make .ini inspection easier. if (const char* p = strstr(name, "###")) name = p; #endif - size_t name_len = strlen(name); - settings->NameOffset = g.SettingsWindowsNames.size(); - g.SettingsWindowsNames.append(name, name + name_len + 1); // Append with zero terminator + const size_t name_len = strlen(name); + + // Allocate chunk + const size_t chunk_size = sizeof(ImGuiWindowSettings) + name_len + 1; + ImGuiWindowSettings* settings = g.SettingsWindows.alloc_chunk(chunk_size); + IM_PLACEMENT_NEW(settings) ImGuiWindowSettings(); settings->ID = ImHashStr(name, name_len); + memcpy(settings->GetName(), name, name_len + 1); // Store with zero terminator + return settings; } ImGuiWindowSettings* ImGui::FindWindowSettings(ImGuiID id) { ImGuiContext& g = *GImGui; - for (int i = 0; i != g.SettingsWindows.Size; i++) - if (g.SettingsWindows[i].ID == id) - return &g.SettingsWindows[i]; + for (ImGuiWindowSettings* settings = g.SettingsWindows.begin(); settings != NULL; settings = g.SettingsWindows.next_chunk(settings)) + if (settings->ID == id) + return settings; return NULL; } @@ -9380,11 +9383,11 @@ static void WindowSettingsHandler_WriteAll(ImGuiContext* ctx, ImGuiSettingsHandl if (window->Flags & ImGuiWindowFlags_NoSavedSettings) continue; - ImGuiWindowSettings* settings = (window->SettingsIdx != -1) ? &g.SettingsWindows[window->SettingsIdx] : ImGui::FindWindowSettings(window->ID); + ImGuiWindowSettings* settings = (window->SettingsOffset != -1) ? g.SettingsWindows.ptr_from_offset(window->SettingsOffset) : ImGui::FindWindowSettings(window->ID); if (!settings) { settings = ImGui::CreateNewWindowSettings(window->Name); - window->SettingsIdx = g.SettingsWindows.index_from_ptr(settings); + window->SettingsOffset = g.SettingsWindows.offset_from_ptr(settings); } IM_ASSERT(settings->ID == window->ID); settings->Pos = ImVec2ih((short)window->Pos.x, (short)window->Pos.y); @@ -9393,11 +9396,10 @@ static void WindowSettingsHandler_WriteAll(ImGuiContext* ctx, ImGuiSettingsHandl } // Write to text buffer - buf->reserve(buf->size() + g.SettingsWindows.Size * 96); // ballpark reserve - for (int i = 0; i != g.SettingsWindows.Size; i++) + buf->reserve(buf->size() + g.SettingsWindows.size() * 6); // ballpark reserve + for (ImGuiWindowSettings* settings = g.SettingsWindows.begin(); settings != NULL; settings = g.SettingsWindows.next_chunk(settings)) { - const ImGuiWindowSettings* settings = &g.SettingsWindows[i]; - const char* settings_name = g.SettingsWindowsNames.c_str() + settings->NameOffset; + const char* settings_name = settings->GetName(); buf->appendf("[%s][%s]\n", handler->TypeName, settings_name); buf->appendf("Pos=%d,%d\n", settings->Pos.x, settings->Pos.y); buf->appendf("Size=%d,%d\n", settings->Size.x, settings->Size.y); diff --git a/imgui_internal.h b/imgui_internal.h index 6fe74a0d..37d46020 100644 --- a/imgui_internal.h +++ b/imgui_internal.h @@ -88,7 +88,6 @@ struct ImGuiTabItem; // Storage for a tab item (within a tab bar) struct ImGuiWindow; // Storage for one window struct ImGuiWindowTempData; // Temporary storage for one window (that's the data which in theory we could ditch at the end of the frame) struct ImGuiWindowSettings; // Storage for a window .ini settings (we keep one of those even if the actual window wasn't instanced during this session) -template struct ImPool; // Basic keyed storage for contiguous instances, slow/amortized insertion, O(1) indexable, O(Log N) queries by ID // Use your programming IDE "Go to definition" facility on the names of the center columns to find the actual flags/enum lists. typedef int ImGuiLayoutType; // -> enum ImGuiLayoutType_ // Enum: Horizontal or vertical @@ -145,6 +144,7 @@ extern IMGUI_API ImGuiContext* GImGui; // Current implicit context pointer // - Helpers: Maths // - Helper: ImBoolVector // - Helper: ImPool<> +// - Helper: ImChunkStream<> //----------------------------------------------------------------------------- // Macros @@ -326,6 +326,28 @@ struct IMGUI_API ImPool int GetSize() const { return Buf.Size; } }; +// Helper: ImChunkStream<> +// Build and iterate a contiguous stream of variable-sized structures. +// This is used by Settings to store persistent data while reducing allocation count. +// We store the chunk size first, and align the final size on 4 bytes boundaries (this what the '(X + 3) & ~3' statement is for) +// The tedious/zealous amount of casting is to avoid -Wcast-align warnings. +template +struct IMGUI_API ImChunkStream +{ + ImVector Buf; + + void clear() { Buf.clear(); } + bool empty() const { return Buf.Size == 0; } + int size() const { return Buf.Size; } + T* alloc_chunk(size_t sz) { size_t HDR_SZ = 4; sz = ((HDR_SZ + sz) + 3u) & ~3u; int off = Buf.Size; Buf.resize(off + (int)sz); ((int*)(void*)(Buf.Data + off))[0] = (int)sz; return (T*)(void*)(Buf.Data + off + (int)HDR_SZ); } + T* begin() { size_t HDR_SZ = 4; if (!Buf.Data) return NULL; return (T*)(void*)(Buf.Data + HDR_SZ); } + T* next_chunk(T* p) { size_t HDR_SZ = 4; IM_ASSERT(p >= begin() && p < end()); p = (T*)(void*)((char*)(void*)p + chunk_size(p)); if (p == (T*)(void*)((char*)end() + HDR_SZ)) return (T*)0; IM_ASSERT(p < end()); return p; } + int chunk_size(const T* p) { return ((const int*)p)[-1]; } + T* end() { return (T*)(void*)(Buf.Data + Buf.Size); } + int offset_from_ptr(const T* p) { IM_ASSERT(p >= begin() && p < end()); const ptrdiff_t off = (const char*)p - Buf.Data; return (int)off; } + T* ptr_from_offset(int off) { IM_ASSERT(off >= 4 && off < Buf.Size); return (T*)(void*)(Buf.Data + off); } +}; + //----------------------------------------------------------------------------- // Misc data structures //----------------------------------------------------------------------------- @@ -681,15 +703,16 @@ struct IMGUI_API ImGuiInputTextState // Windows data saved in imgui.ini file // Because we never destroy or rename ImGuiWindowSettings, we can store the names in a separate buffer easily. +// (this is designed to be stored in a ImChunkStream buffer, with the variable-length Name following our structure) struct ImGuiWindowSettings { - int NameOffset; // Offset into SettingsWindowNames[] ImGuiID ID; ImVec2ih Pos; ImVec2ih Size; bool Collapsed; - ImGuiWindowSettings() { NameOffset = -1; ID = 0; Pos = Size = ImVec2ih(0, 0); Collapsed = false; } + ImGuiWindowSettings() { ID = 0; Pos = Size = ImVec2ih(0, 0); Collapsed = false; } + char* GetName() { return (char*)(this + 1); } }; struct ImGuiSettingsHandler @@ -1053,12 +1076,11 @@ struct ImGuiContext ImVec2 PlatformImeLastPos; // Settings - bool SettingsLoaded; - float SettingsDirtyTimer; // Save .ini Settings to memory when time reaches zero - ImGuiTextBuffer SettingsIniData; // In memory .ini settings - ImVector SettingsHandlers; // List of .ini settings handlers - ImVector SettingsWindows; // ImGuiWindow .ini settings entries (parsed from the last loaded .ini file and maintained on saving) - ImGuiTextBuffer SettingsWindowsNames; // Names for SettingsWindows + bool SettingsLoaded; + float SettingsDirtyTimer; // Save .ini Settings to memory when time reaches zero + ImGuiTextBuffer SettingsIniData; // In memory .ini settings + ImVector SettingsHandlers; // List of .ini settings handlers + ImChunkStream SettingsWindows; // ImGuiWindow .ini settings entries // Logging bool LogEnabled; @@ -1369,7 +1391,7 @@ struct IMGUI_API ImGuiWindow ImGuiStorage StateStorage; ImVector ColumnsStorage; float FontWindowScale; // User scale multiplier per-window, via SetWindowFontScale() - int SettingsIdx; // Index into SettingsWindow[] (indices are always valid as we only grow the array from the back) + int SettingsOffset; // Offset into SettingsWindows[] (offsets are always valid as we only grow the array from the back) ImDrawList* DrawList; // == &DrawListInst (for backward compatibility reason with code using imgui_internal.h we keep this a pointer) ImDrawList DrawListInst;