editor, main: add fmtlib dependency

snprintf in imgui code is slow.

8 files changed, 58 insertions, 17 deletions

diff --git a/.gitmodules b/.gitmodules
index 0dbe42d2..b24cda5b 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -19,3 +19,6 @@
 [submodule "sdl2"]
 	path = external/sdl2
 	url = https://github.com/libsdl-org/SDL.git
+[submodule "external/fmt"]
+	path = external/fmt
+	url = https://github.com/fmtlib/fmt.git
diff --git a/compat/format.hpp b/compat/format.hpp
new file mode 100644
index 00000000..e126e77b
--- /dev/null
+++ b/compat/format.hpp
@@ -0,0 +1,20 @@
+#pragma once
+#include <fmt/core.h>
+#include <fmt/compile.h>
+
+namespace floormat {
+
+using namespace fmt::literals;
+
+template<std::size_t N, typename Fmt, typename... Xs>
+std::size_t snformat(char(&buf)[N], Fmt&& fmt, Xs&&... args)
+{
+    constexpr std::size_t n = N > 0 ? N - 1 : 0;
+    auto result = fmt::format_to_n(buf, n, std::forward<Fmt>(fmt), std::forward<Xs>(args)...);
+    const auto len = std::min(n, result.size);
+    if constexpr(N > 0)
+        buf[len] = '\0';
+    return len;
+}
+
+} // namespace floormat
diff --git a/editor/CMakeLists.txt b/editor/CMakeLists.txt
index 0ce1773a..77a2a73e 100644
--- a/editor/CMakeLists.txt
+++ b/editor/CMakeLists.txt
@@ -9,7 +9,7 @@ else()
     set_property(SOURCE "${res}" APPEND PROPERTY COMPILE_OPTIONS "-w")
 endif()
 
-link_libraries(MagnumIntegration::ImGui)
+link_libraries(MagnumIntegration::ImGui fmt::fmt)
 
 add_executable(${self} "${sources}" "${res}" "../loader/loader-impl.cpp")
 target_link_libraries(${self} ${PROJECT_NAME}-main)
diff --git a/editor/imgui-raii.hpp b/editor/imgui-raii.hpp
index ab317095..5920e7d9 100644
--- a/editor/imgui-raii.hpp
+++ b/editor/imgui-raii.hpp
@@ -2,9 +2,8 @@
 
 #include <Corrade/Containers/StringView.h>
 #include <Magnum/Math/Color.h>
-#ifndef __CLION_IDE__zz
 #include <imgui.h>
-#endif
+#include <imgui_internal.h>
 
 namespace floormat::imgui {
 
@@ -82,4 +81,16 @@ struct raii_wrapper final
     return {[]{ ImGui::PopStyleColor(); }};
 }
 
+[[maybe_unused]] static inline void text(const char* str, std::size_t len, ImGuiTextFlags_ flags = ImGuiTextFlags_NoWidthForLargeClippedText)
+{
+    ImGui::TextEx(str, str + len, flags);
+}
+
+template<std::size_t N>
+[[maybe_unused]] static inline void text(const char (&buf)[N], ImGuiTextFlags_ flags = ImGuiTextFlags_NoWidthForLargeClippedText)
+{
+    static_assert(N > 0);
+    ImGui::TextEx(buf, buf + N - 1, flags);
+}
+
 } // namespace floormat::imgui
diff --git a/editor/imgui.cpp b/editor/imgui.cpp
index 84827ba3..b29c4f6c 100644
--- a/editor/imgui.cpp
+++ b/editor/imgui.cpp
@@ -1,6 +1,7 @@
 #include "app.hpp"
 #include "floormat/main.hpp"
 #include "src/tile-atlas.hpp"
+#include "compat/format.hpp"
 
 #include <Magnum/GL/Renderer.h>
 #include "imgui-raii.hpp"
@@ -104,11 +105,11 @@ static void draw_editor_pane_atlas(tile_editor& ed, StringView name, const std::
         if (ed.is_atlas_selected(atlas))
         {
             ImGui::SameLine();
-            ImGui::Text(" (selected)");
+            text(" (selected)");
         }
-        std::snprintf(buf, sizeof(buf), "%zu", N);
+        const auto len = snformat(buf, FMT_COMPILE("{:d}"), N);
         ImGui::SameLine(window_width - ImGui::CalcTextSize(buf).x - style.FramePadding.x - 4);
-        ImGui::Text("%s", buf);
+        text(buf, len);
     };
     if (const auto flags = ImGuiTreeNodeFlags_(ImGuiTreeNodeFlags_SpanFullWidth | ImGuiTreeNodeFlags_Framed);
         auto b = tree_node(name.data(), flags))
@@ -123,7 +124,6 @@ static void draw_editor_pane_atlas(tile_editor& ed, StringView name, const std::
         for (std::size_t i = 0; i < N; i++)
         {
             const bool selected = ed.is_tile_selected(atlas, i);
-
             if (i > 0 && i % per_row == 0)
                 ImGui::NewLine();
 
@@ -134,7 +134,7 @@ static void draw_editor_pane_atlas(tile_editor& ed, StringView name, const std::
                 perm_selected ? push_style_color(ImGuiCol_ButtonHovered, color_perm_selected) : raii_wrapper{},
             };
 
-            std::snprintf(buf, sizeof(buf), "##item_%zu", i);
+            snformat(buf, FMT_COMPILE("##item_{}"), i);
             const auto uv = atlas->texcoords_for_id(i);
             constexpr ImVec2 size_2 = { TILE_SIZE[0]*.5f, TILE_SIZE[1]*.5f };
             ImGui::ImageButton(buf, (void*)&atlas->texture(), size_2,
@@ -193,7 +193,7 @@ void app::draw_fps()
     const auto frame_time = M->smoothed_dt();
     char buf[16];
     const double hz = frame_time > 1e-6f ? (int)std::round(10./(double)frame_time + .05) * .1 : 9999;
-    snprintf(buf, sizeof(buf), "%.1f FPS", hz);
+    snformat(buf, FMT_COMPILE("{:.1f} FPS"), hz);
     const ImVec2 size = ImGui::CalcTextSize(buf);
     ImDrawList& draw = *ImGui::GetForegroundDrawList();
     draw.AddText({M->window_size()[0] - size.x - 4, 3}, ImGui::ColorConvertFloat4ToU32({0, 1, 0, 1}), buf);
@@ -208,7 +208,7 @@ void app::draw_tile_under_cursor()
     const auto coord = *cursor.tile;
     const auto chunk = coord.chunk();
     const auto local = coord.local();
-    snprintf(buf, sizeof(buf), "%hd:%hd - %hhu:%hhu", chunk.x, chunk.y, local.x, local.y);
+    snformat(buf, FMT_COMPILE("{}:{} - {}:{}"), chunk.x, chunk.y, local.x, local.y);
     const auto size = ImGui::CalcTextSize(buf);
     const auto window_size = M->window_size();
 
diff --git a/external/CMakeLists.txt b/external/CMakeLists.txt
index fe774f8b..45e5728b 100644
--- a/external/CMakeLists.txt
+++ b/external/CMakeLists.txt
@@ -42,12 +42,14 @@ if(FLOORMAT_SUBMODULE-DEPENDENCIES)
          NLOHMANN_JSON_CONFIG_INSTALL_DIR       "share/cmake/nlohmann_json"
     )
     sets(BOOL
-         JSON_Diagnostics        ON
-         JSON_Install            ON
-         JSON_MultipleHeaders    ON
-         JSON_SystemInclude      ON
-    )
-    sets(BOOL
+
+         FMT_SYSTEM_HEADERS                     ON
+
+         JSON_Diagnostics                       ON
+         JSON_Install                           ON
+         JSON_MultipleHeaders                   ON
+         JSON_SystemInclude                     ON
+
          CORRADE_BUILD_STATIC                   OFF
          CORRADE_BUILD_TESTS                    OFF
          CORRADE_BUILD_DEPRECATED               OFF
@@ -154,6 +156,7 @@ if(FLOORMAT_SUBMODULE-DEPENDENCIES)
     add_subdirectory(magnum)
     add_subdirectory(magnum-plugins)
     add_subdirectory(magnum-integration)
+    add_subdirectory(fmt)
 endif()
 
 if(FLOORMAT_SUBMODULE-DEPENDENCIES)
@@ -171,4 +174,8 @@ find_package(Magnum QUIET REQUIRED)
 find_package(MagnumPlugins QUIET REQUIRED)
 find_package(MagnumIntegration QUIET REQUIRED ImGui)
 
+if(NOT FLOORMAT_SUBMODULE-DEPENDENCIES)
+    find_package(fmt QUIET REQUIRED)
+endif()
+
 fm_run_hook(fm-userconfig-external-post)
diff --git a/external/fmt b/external/fmt
new file mode 160000
+Subproject d2e89c8b080394e996d449371267365c223ca76
diff --git a/main/CMakeLists.txt b/main/CMakeLists.txt
index 66737793..1ad37734 100644
--- a/main/CMakeLists.txt
+++ b/main/CMakeLists.txt
@@ -2,7 +2,7 @@ set(self ${PROJECT_NAME}-main)
 file(GLOB sources "*.cpp" CONFIGURE_ARGS)
 
 link_libraries(${PROJECT_NAME})
-link_libraries(Magnum::Sdl2Application Corrade::Containers Magnum::GL Magnum::Trade)
+link_libraries(Magnum::Sdl2Application Corrade::Containers Magnum::GL Magnum::Trade fmt::fmt)
 
 add_library(${self} STATIC "${sources}")