Merge pull request #1599 from falbrechtskirchinger/rounding

Add `iround()` and round PointF->PointInt by default

Author: Flamefire

libs/common/include/Point.h

@@ -4,6 +4,7 @@
 
 #pragma once
 
+#include "helpers/mathFuncs.h"
 #include <algorithm>
 #include <cstdint>
 #include <limits>
@@ -21,12 +22,27 @@ struct Point //-V690
     using ElementType = T;
     static_assert(std::is_arithmetic<ElementType>::value, "Requires an arithmetic type");
 
+    struct Truncate_t
+    {
+        constexpr explicit Truncate_t() = default;
+    };
+
+    static constexpr Truncate_t Truncate{};
+
     T x, y;
     constexpr Point() noexcept : x(getInvalidValue()), y(getInvalidValue()) {}
     constexpr Point(const T x, const T y) noexcept : x(x), y(y) {}
-    template<typename U>
+    template<typename U, std::enable_if_t<!(std::is_integral<T>::value && std::is_floating_point<U>::value), int> = 0>
     constexpr explicit Point(const Point<U>& pt) noexcept : x(static_cast<T>(pt.x)), y(static_cast<T>(pt.y))
     {}
+    /// Convert floating-point to integer by truncating
+    template<typename U, std::enable_if_t<std::is_integral<T>::value && std::is_floating_point<U>::value, int> = 0>
+    constexpr explicit Point(Truncate_t, const Point<U>& pt) noexcept : x(static_cast<T>(pt.x)), y(static_cast<T>(pt.y))
+    {}
+    /// Convert floating-point to integer with rounding (default behavior)
+    template<typename U, std::enable_if_t<std::is_integral<T>::value && std::is_floating_point<U>::value, int> = 0>
+    constexpr explicit Point(const Point<U>& pt) noexcept : x(helpers::iround<T>(pt.x)), y(helpers::iround<T>(pt.y))
+    {}
     constexpr Point(const Point&) = default;
     constexpr Point& operator=(const Point&) = default;
 

libs/common/include/helpers/mathFuncs.h

@@ -4,6 +4,8 @@
 
 #pragma once
 
+#include "RTTR_Assert.h"
+#include <cmath>
 #include <type_traits>
 
 namespace helpers {
@@ -79,4 +81,18 @@ constexpr T inverseLerp(const T startVal, const T endVal, const T value) noexcep
 {
     return (value - startVal) / (endVal - startVal);
 }
+
+// TODO can be constexpr in C++20
+/// Arithmetically round floating point values to integers
+template<typename IntType, typename FloatType,
+         std::enable_if_t<std::is_integral<IntType>::value && std::is_floating_point<FloatType>::value, int> = 0>
+IntType iround(const FloatType val) noexcept
+{
+    RTTR_Assert(std::isfinite(val));
+
+    if(std::is_unsigned<IntType>::value)
+        RTTR_Assert_Msg(!(val < 0), "Floating-point value must not be negative when casting to unsigned integer type.");
+
+    return static_cast<IntType>(std::lround(val));
+}
 } // namespace helpers

libs/s25main/FrameCounter.cpp

@@ -3,9 +3,9 @@
 // SPDX-License-Identifier: GPL-2.0-or-later
 
 #include "FrameCounter.h"
+#include "helpers/mathFuncs.h"
 #include "helpers/win32_nanosleep.h" // IWYU pragma: keep
 #include <algorithm>
-#include <cmath>
 
 //-V:clock::time_point:813
 
@@ -36,7 +36,7 @@ unsigned FrameCounter::getCurFrameRate() const
     if(timeDiff == clock::duration::zero())
         return 0;
     using dSeconds = std::chrono::duration<double>;
-    return std::lround(curNumFrames_ / std::chrono::duration_cast<dSeconds>(timeDiff).count());
+    return helpers::iround<unsigned>(curNumFrames_ / std::chrono::duration_cast<dSeconds>(timeDiff).count());
 }
 
 FrameTimer::FrameTimer(int targetFramerate, unsigned maxLagFrames, clock::time_point curTime)

libs/s25main/TerrainRenderer.cpp

@@ -886,7 +886,7 @@ void TerrainRenderer::PrepareWaysPoint(PreparedRoads& sorted_roads, const GameWo
                                        const Position& offset) const
 {
     const WorldDescription& desc = gwViewer.GetWorld().GetDescription();
-    Position startPos = Position(GetVertexPos(pt)) + offset;
+    Position startPos = Position(Position::Truncate, GetVertexPos(pt)) + offset;
 
     Visibility visibility = gwViewer.GetVisibility(pt);
 
@@ -902,7 +902,7 @@ void TerrainRenderer::PrepareWaysPoint(PreparedRoads& sorted_roads, const GameWo
         const Direction targetDir = toDirection(dir);
         MapPoint ta = gwViewer.GetNeighbour(pt, targetDir);
 
-        Position endPos = Position(GetVertexPos(ta)) + offset;
+        Position endPos = Position(Position::Truncate, GetVertexPos(ta)) + offset;
         Position diff = startPos - endPos;
 
         // Gehen wir über einen Kartenrand (horizontale Richung?)

libs/s25main/controls/ctrlProgress.cpp

@@ -6,9 +6,9 @@
 #include "CollisionDetection.h"
 #include "Loader.h"
 #include "WindowManager.h"
+#include "helpers/mathFuncs.h"
 #include "ogl/FontStyle.h"
 #include "ogl/glFont.h"
-#include <cmath>
 
 ctrlProgress::ctrlProgress(Window* parent, const unsigned id, const DrawPoint& pos, const Extent& size,
                            const TextureColor tc, unsigned short button_minus, unsigned short button_plus,
@@ -140,8 +140,8 @@ bool ctrlProgress::Msg_LeftDown(const MouseCoords& mc)
     Extent progressSize = GetSize() - Extent((GetSize().y + 1) * 2, 8) - padding_ * 2u;
     if(IsPointInRect(mc.GetPos(), Rect(progressOrigin, progressSize)))
     {
-        position = static_cast<uint16_t>(
-          std::lround(static_cast<double>((mc.pos.x - progressOrigin.x) * maximum) / progressSize.x));
+        position =
+          helpers::iround<uint16_t>(static_cast<double>((mc.pos.x - progressOrigin.x) * maximum) / progressSize.x);
 
         if(GetParent())
             GetParent()->Msg_ProgressChange(GetID(), position);

libs/s25main/controls/ctrlTable.cpp

@@ -8,11 +8,11 @@
 #include "ctrlScrollBar.h"
 #include "driver/KeyEvent.h"
 #include "driver/MouseCoords.h"
+#include "helpers/mathFuncs.h"
 #include "ogl/glFont.h"
 #include "s25util/StringConversion.h"
 #include "s25util/strAlgos.h"
 #include <algorithm>
-#include <cmath>
 #include <numeric>
 #include <sstream>
 
@@ -465,7 +465,7 @@ void ctrlTable::ResetButtonWidths()
     for(unsigned i = 0; i < columns_.size(); ++i)
     {
         auto* button = GetCtrl<ctrlButton>(i + 1);
-        button->SetWidth(std::lround(columns_[i].width * sizeFactor));
+        button->SetWidth(helpers::iround<unsigned>(columns_[i].width * sizeFactor));
         button->SetPos(btPos);
         btPos.x += button->GetSize().x;
     }

libs/s25main/ingameWindows/iwConnecting.cpp

@@ -8,11 +8,11 @@
 #include "controls/ctrlPercent.h"
 #include "controls/ctrlText.h"
 #include "desktops/dskGameLobby.h"
+#include "helpers/mathFuncs.h"
 #include "iwMsgbox.h"
 #include "network/GameClient.h"
 #include "gameData/const_gui_ids.h"
 #include "s25util/colors.h"
-#include <cmath>
 
 namespace {
 enum
@@ -92,7 +92,7 @@ void iwConnecting::CI_NextConnectState(const ConnectState cs)
 
 void iwConnecting::CI_MapPartReceived(uint32_t bytesReceived, uint32_t bytesTotal)
 {
-    downloadProgress_ = static_cast<unsigned short>(std::lround(bytesReceived * 100. / bytesTotal));
+    downloadProgress_ = helpers::iround<unsigned short>(bytesReceived * 100. / bytesTotal);
 }
 
 void iwConnecting::setStatus(const std::string& status)

libs/s25main/network/GameServer.cpp

@@ -16,6 +16,7 @@
 #include "commonDefines.h"
 #include "files.h"
 #include "helpers/containerUtils.h"
+#include "helpers/mathFuncs.h"
 #include "helpers/random.h"
 #include "network/CreateServerInfo.h"
 #include "network/GameMessages.h"
@@ -36,7 +37,6 @@
 #include <boost/filesystem.hpp>
 #include <boost/nowide/convert.hpp>
 #include <boost/nowide/fstream.hpp>
-#include <cmath>
 #include <helpers/chronoIO.h>
 #include <iomanip>
 #include <iterator>
@@ -763,7 +763,7 @@ void GameServer::ExecuteNWF()
         using MsDouble = duration<double, std::milli>;
         double newNWFLen =
           framesinfo.nwf_length * framesinfo.gf_length / duration_cast<MsDouble>(framesinfo.gfLengthReq);
-        newInfo.nextNWF = lastNWF + std::max(1l, std::lround(newNWFLen));
+        newInfo.nextNWF = lastNWF + std::max(1u, helpers::iround<unsigned>(newNWFLen));
     }
     SendNWFDone(newInfo);
 }

libs/s25main/world/GameWorld.cpp

@@ -17,6 +17,7 @@
 #include "figures/nofPassiveSoldier.h"
 #include "figures/nofScout_Free.h"
 #include "helpers/containerUtils.h"
+#include "helpers/mathFuncs.h"
 #include "helpers/reverse.h"
 #include "lua/LuaInterfaceGame.h"
 #include "notifications/BuildingNote.h"
@@ -37,7 +38,6 @@
 #include "gameData/MilitaryConsts.h"
 #include "gameData/TerrainDesc.h"
 #include <algorithm>
-#include <cmath>
 #include <functional>
 #include <set>
 #include <stdexcept>
@@ -1357,8 +1357,8 @@ void GameWorld::PlaceAndFixWater()
             }
         }
         if(minHumidity)
-            curNodeResource = Resource(
-              ResourceType::Water, waterEverywhere ? 7 : static_cast<uint8_t>(std::lround(minHumidity * 7. / 100.)));
+            curNodeResource =
+              Resource(ResourceType::Water, waterEverywhere ? 7 : helpers::iround<uint8_t>(minHumidity * 7. / 100.));
         else
             curNodeResource = Resource(ResourceType::Nothing, 0);
 

tests/common/testPoint.cpp

@@ -283,3 +283,12 @@ BOOST_AUTO_TEST_CASE(ProdOfComponents)
     Point<float> ptF(256.5, 256.5);
     BOOST_TEST(prodOfComponents(ptF) == 256.5f * 256.5f);
 }
+
+BOOST_AUTO_TEST_CASE(ConvertFloatToIntPoints)
+{
+    BOOST_TEST(Point<int>(Point<float>(1.5f, 3.4f)) == Point<int>(2, 3));
+    BOOST_TEST(Point<int>(Point<int>::Truncate, Point<float>(1.5f, 3.4f)) == Point<int>(1, 3));
+
+    BOOST_TEST(Point<int>(Point<float>(-1.5f, -3.4f)) == Point<int>(-2, -3));
+    BOOST_TEST(Point<int>(Point<int>::Truncate, Point<float>(-1.5f, -3.4f)) == Point<int>(-1, -3));
+}