feat: Initial Physics Code From Previous Repo

This commit is contained in:
Syntriax 2024-01-23 18:39:25 +03:00
parent d08495afbb
commit a9485475c7
22 changed files with 1184 additions and 0 deletions

484
.gitignore vendored Normal file
View File

@ -0,0 +1,484 @@
## Ignore Visual Studio temporary files, build results, and
## files generated by popular Visual Studio add-ons.
##
## Get latest from `dotnet new gitignore`
# dotenv files
.env
# User-specific files
*.rsuser
*.suo
*.user
*.userosscache
*.sln.docstates
# User-specific files (MonoDevelop/Xamarin Studio)
*.userprefs
# Mono auto generated files
mono_crash.*
# Build results
[Dd]ebug/
[Dd]ebugPublic/
[Rr]elease/
[Rr]eleases/
x64/
x86/
[Ww][Ii][Nn]32/
[Aa][Rr][Mm]/
[Aa][Rr][Mm]64/
bld/
[Bb]in/
[Oo]bj/
[Ll]og/
[Ll]ogs/
# Visual Studio 2015/2017 cache/options directory
.vs/
# Uncomment if you have tasks that create the project's static files in wwwroot
#wwwroot/
# Visual Studio 2017 auto generated files
Generated\ Files/
# MSTest test Results
[Tt]est[Rr]esult*/
[Bb]uild[Ll]og.*
# NUnit
*.VisualState.xml
TestResult.xml
nunit-*.xml
# Build Results of an ATL Project
[Dd]ebugPS/
[Rr]eleasePS/
dlldata.c
# Benchmark Results
BenchmarkDotNet.Artifacts/
# .NET
project.lock.json
project.fragment.lock.json
artifacts/
# Tye
.tye/
# ASP.NET Scaffolding
ScaffoldingReadMe.txt
# StyleCop
StyleCopReport.xml
# Files built by Visual Studio
*_i.c
*_p.c
*_h.h
*.ilk
*.meta
*.obj
*.iobj
*.pch
*.pdb
*.ipdb
*.pgc
*.pgd
*.rsp
*.sbr
*.tlb
*.tli
*.tlh
*.tmp
*.tmp_proj
*_wpftmp.csproj
*.log
*.tlog
*.vspscc
*.vssscc
.builds
*.pidb
*.svclog
*.scc
# Chutzpah Test files
_Chutzpah*
# Visual C++ cache files
ipch/
*.aps
*.ncb
*.opendb
*.opensdf
*.sdf
*.cachefile
*.VC.db
*.VC.VC.opendb
# Visual Studio profiler
*.psess
*.vsp
*.vspx
*.sap
# Visual Studio Trace Files
*.e2e
# TFS 2012 Local Workspace
$tf/
# Guidance Automation Toolkit
*.gpState
# ReSharper is a .NET coding add-in
_ReSharper*/
*.[Rr]e[Ss]harper
*.DotSettings.user
# TeamCity is a build add-in
_TeamCity*
# DotCover is a Code Coverage Tool
*.dotCover
# AxoCover is a Code Coverage Tool
.axoCover/*
!.axoCover/settings.json
# Coverlet is a free, cross platform Code Coverage Tool
coverage*.json
coverage*.xml
coverage*.info
# Visual Studio code coverage results
*.coverage
*.coveragexml
# NCrunch
_NCrunch_*
.*crunch*.local.xml
nCrunchTemp_*
# MightyMoose
*.mm.*
AutoTest.Net/
# Web workbench (sass)
.sass-cache/
# Installshield output folder
[Ee]xpress/
# DocProject is a documentation generator add-in
DocProject/buildhelp/
DocProject/Help/*.HxT
DocProject/Help/*.HxC
DocProject/Help/*.hhc
DocProject/Help/*.hhk
DocProject/Help/*.hhp
DocProject/Help/Html2
DocProject/Help/html
# Click-Once directory
publish/
# Publish Web Output
*.[Pp]ublish.xml
*.azurePubxml
# Note: Comment the next line if you want to checkin your web deploy settings,
# but database connection strings (with potential passwords) will be unencrypted
*.pubxml
*.publishproj
# Microsoft Azure Web App publish settings. Comment the next line if you want to
# checkin your Azure Web App publish settings, but sensitive information contained
# in these scripts will be unencrypted
PublishScripts/
# NuGet Packages
*.nupkg
# NuGet Symbol Packages
*.snupkg
# The packages folder can be ignored because of Package Restore
**/[Pp]ackages/*
# except build/, which is used as an MSBuild target.
!**/[Pp]ackages/build/
# Uncomment if necessary however generally it will be regenerated when needed
#!**/[Pp]ackages/repositories.config
# NuGet v3's project.json files produces more ignorable files
*.nuget.props
*.nuget.targets
# Microsoft Azure Build Output
csx/
*.build.csdef
# Microsoft Azure Emulator
ecf/
rcf/
# Windows Store app package directories and files
AppPackages/
BundleArtifacts/
Package.StoreAssociation.xml
_pkginfo.txt
*.appx
*.appxbundle
*.appxupload
# Visual Studio cache files
# files ending in .cache can be ignored
*.[Cc]ache
# but keep track of directories ending in .cache
!?*.[Cc]ache/
# Others
ClientBin/
~$*
*~
*.dbmdl
*.dbproj.schemaview
*.jfm
*.pfx
*.publishsettings
orleans.codegen.cs
# Including strong name files can present a security risk
# (https://github.com/github/gitignore/pull/2483#issue-259490424)
#*.snk
# Since there are multiple workflows, uncomment next line to ignore bower_components
# (https://github.com/github/gitignore/pull/1529#issuecomment-104372622)
#bower_components/
# RIA/Silverlight projects
Generated_Code/
# Backup & report files from converting an old project file
# to a newer Visual Studio version. Backup files are not needed,
# because we have git ;-)
_UpgradeReport_Files/
Backup*/
UpgradeLog*.XML
UpgradeLog*.htm
ServiceFabricBackup/
*.rptproj.bak
# SQL Server files
*.mdf
*.ldf
*.ndf
# Business Intelligence projects
*.rdl.data
*.bim.layout
*.bim_*.settings
*.rptproj.rsuser
*- [Bb]ackup.rdl
*- [Bb]ackup ([0-9]).rdl
*- [Bb]ackup ([0-9][0-9]).rdl
# Microsoft Fakes
FakesAssemblies/
# GhostDoc plugin setting file
*.GhostDoc.xml
# Node.js Tools for Visual Studio
.ntvs_analysis.dat
node_modules/
# Visual Studio 6 build log
*.plg
# Visual Studio 6 workspace options file
*.opt
# Visual Studio 6 auto-generated workspace file (contains which files were open etc.)
*.vbw
# Visual Studio 6 auto-generated project file (contains which files were open etc.)
*.vbp
# Visual Studio 6 workspace and project file (working project files containing files to include in project)
*.dsw
*.dsp
# Visual Studio 6 technical files
*.ncb
*.aps
# Visual Studio LightSwitch build output
**/*.HTMLClient/GeneratedArtifacts
**/*.DesktopClient/GeneratedArtifacts
**/*.DesktopClient/ModelManifest.xml
**/*.Server/GeneratedArtifacts
**/*.Server/ModelManifest.xml
_Pvt_Extensions
# Paket dependency manager
.paket/paket.exe
paket-files/
# FAKE - F# Make
.fake/
# CodeRush personal settings
.cr/personal
# Python Tools for Visual Studio (PTVS)
__pycache__/
*.pyc
# Cake - Uncomment if you are using it
# tools/**
# !tools/packages.config
# Tabs Studio
*.tss
# Telerik's JustMock configuration file
*.jmconfig
# BizTalk build output
*.btp.cs
*.btm.cs
*.odx.cs
*.xsd.cs
# OpenCover UI analysis results
OpenCover/
# Azure Stream Analytics local run output
ASALocalRun/
# MSBuild Binary and Structured Log
*.binlog
# NVidia Nsight GPU debugger configuration file
*.nvuser
# MFractors (Xamarin productivity tool) working folder
.mfractor/
# Local History for Visual Studio
.localhistory/
# Visual Studio History (VSHistory) files
.vshistory/
# BeatPulse healthcheck temp database
healthchecksdb
# Backup folder for Package Reference Convert tool in Visual Studio 2017
MigrationBackup/
# Ionide (cross platform F# VS Code tools) working folder
.ionide/
# Fody - auto-generated XML schema
FodyWeavers.xsd
# VS Code files for those working on multiple tools
.vscode/*
!.vscode/settings.json
!.vscode/tasks.json
!.vscode/launch.json
!.vscode/extensions.json
*.code-workspace
# Local History for Visual Studio Code
.history/
# Windows Installer files from build outputs
*.cab
*.msi
*.msix
*.msm
*.msp
# JetBrains Rider
*.sln.iml
.idea
##
## Visual studio for Mac
##
# globs
Makefile.in
*.userprefs
*.usertasks
config.make
config.status
aclocal.m4
install-sh
autom4te.cache/
*.tar.gz
tarballs/
test-results/
# Mac bundle stuff
*.dmg
*.app
# content below from: https://github.com/github/gitignore/blob/master/Global/macOS.gitignore
# General
.DS_Store
.AppleDouble
.LSOverride
# Icon must end with two \r
Icon
# Thumbnails
._*
# Files that might appear in the root of a volume
.DocumentRevisions-V100
.fseventsd
.Spotlight-V100
.TemporaryItems
.Trashes
.VolumeIcon.icns
.com.apple.timemachine.donotpresent
# Directories potentially created on remote AFP share
.AppleDB
.AppleDesktop
Network Trash Folder
Temporary Items
.apdisk
# content below from: https://github.com/github/gitignore/blob/master/Global/Windows.gitignore
# Windows thumbnail cache files
Thumbs.db
ehthumbs.db
ehthumbs_vista.db
# Dump file
*.stackdump
# Folder config file
[Dd]esktop.ini
# Recycle Bin used on file shares
$RECYCLE.BIN/
# Windows Installer files
*.cab
*.msi
*.msix
*.msm
*.msp
# Windows shortcuts
*.lnk
# Vim temporary swap files
*.swp

View File

@ -0,0 +1,19 @@
using System;
using System.Collections.Generic;
using Syntriax.Engine.Core;
using Syntriax.Engine.Core.Abstract;
namespace Syntriax.Engine.Physics2D.Abstract;
public interface ICollider2D : IBehaviour, IAssignableTransform
{
Action<ICollider2D, ICollider2D>? OnCollisionPreResolve { get; set; }
IRigidBody2D? RigidBody2D { get; }
IList<Vector2D> Vertices { get; }
bool CheckCollision(Vector2D point);
void Recalculate();
}

View File

@ -0,0 +1,6 @@
namespace Syntriax.Engine.Physics2D.Abstract;
public interface ICollisionResolver2D
{
void ResolveCollision(ICollider2D colliderA, ICollider2D colliderB);
}

View File

@ -0,0 +1,11 @@
namespace Syntriax.Engine.Physics2D.Abstract;
public interface IPhysicsEngine2D
{
int IterationCount { get; set; }
void AddRigidBody(IRigidBody2D rigidBody);
void RemoveRigidBody(IRigidBody2D rigidBody);
void Step(float deltaTime);
}

View File

@ -0,0 +1,7 @@
namespace Syntriax.Engine.Physics2D.Abstract;
public interface IPhysicsMaterial2D
{
float Friction { get; }
float Restitution { get; }
}

View File

@ -0,0 +1,14 @@
using Syntriax.Engine.Core;
using Syntriax.Engine.Core.Abstract;
namespace Syntriax.Engine.Physics2D.Abstract;
public interface IRigidBody2D : IBehaviour, IAssignableTransform
{
IPhysicsMaterial2D Material { get; set; }
Vector2D Velocity { get; set; }
float AngularVelocity { get; set; }
float Mass { get; set; }
}

View File

@ -0,0 +1,67 @@
using System;
using System.Collections.Generic;
using Syntriax.Engine.Core;
using Syntriax.Engine.Core.Abstract;
using Syntriax.Engine.Physics2D.Abstract;
using Syntriax.Engine.Physics2D.Primitives;
namespace Syntriax.Engine.Physics2D;
public class Collider2DAABBBehaviour : BehaviourOverride, ICollider2D
{
public AABB AABBLocal { get; set; } = null!;
public AABB AABBWorld { get; private set; } = null!;
private IRigidBody2D? _rigidBody2D = null;
private List<Vector2D> _vertices = new List<Vector2D>(4);
public IRigidBody2D? RigidBody2D
{
get
{
if (_rigidBody2D is null)
BehaviourController.TryGetBehaviour(out _rigidBody2D);
return _rigidBody2D;
}
}
public Action<ICollider2D, ICollider2D>? OnCollisionPreResolve { get; set; } = null;
public Action<IAssignableTransform>? OnTransformAssigned { get => GameObject.OnTransformAssigned; set => GameObject.OnTransformAssigned = value; }
ITransform IAssignableTransform.Transform => Transform;
public bool Assign(ITransform transform) => GameObject.Assign(transform);
public IList<Vector2D> Vertices => _vertices;
public bool CheckCollision(Vector2D point)
{
return AABBWorld.Overlaps(point);
}
public void Recalculate()
{
AABBWorld = new AABB(
AABBLocal.LowerBoundary.Scale(Transform.Scale) + Transform.Position,
AABBLocal.UpperBoundary.Scale(Transform.Scale) + Transform.Position
);
Vertices.Clear();
Vertices.Add(AABBWorld.LowerBoundary);
Vertices.Add(new Vector2D(AABBWorld.LowerBoundary.X, AABBWorld.UpperBoundary.Y));
Vertices.Add(AABBWorld.UpperBoundary);
Vertices.Add(new Vector2D(AABBWorld.UpperBoundary.X, AABBWorld.LowerBoundary.Y));
}
public Collider2DAABBBehaviour(Vector2D lowerBoundary, Vector2D upperBoundary)
{
AABBLocal = new AABB(lowerBoundary, upperBoundary);
AABBWorld = new AABB(lowerBoundary, upperBoundary);
}
public Collider2DAABBBehaviour()
{
AABBLocal = new(Vector2D.Zero, Vector2D.Zero);
AABBWorld = new(Vector2D.Zero, Vector2D.Zero);
}
}

View File

@ -0,0 +1,9 @@
using Microsoft.Xna.Framework;
namespace Syntriax.Engine.Physics2D;
public record CollisionInformation
(
Vector2 Normal,
Vector2 ContactPosition
);

View File

@ -0,0 +1,13 @@
<Project Sdk="Microsoft.NET.Sdk">
<ItemGroup>
<ProjectReference Include="..\Engine.Core\Engine.Core.csproj" />
</ItemGroup>
<PropertyGroup>
<TargetFramework>net8.0</TargetFramework>
<ImplicitUsings>disable</ImplicitUsings>
<Nullable>enable</Nullable>
</PropertyGroup>
</Project>

View File

@ -0,0 +1,75 @@
using System;
using System.Collections.Generic;
using Syntriax.Engine.Core;
using Syntriax.Engine.Core.Abstract;
using Syntriax.Engine.Physics2D.Abstract;
using Syntriax.Engine.Physics2D.Primitives;
namespace Syntriax.Engine.Physics2D;
public class PhysicsEngine2D : IPhysicsEngine2D
{
private List<IRigidBody2D> rigidBodies = new List<IRigidBody2D>(32);
private List<ICollider2D> colliders = new List<ICollider2D>(64);
private int _iterationCount = 1;
public int IterationCount { get => _iterationCount; set => _iterationCount = value < 1 ? 1 : value; }
public void AddRigidBody(IRigidBody2D rigidBody)
{
if (rigidBodies.Contains(rigidBody))
return;
rigidBodies.Add(rigidBody);
foreach (var collider2D in rigidBody.BehaviourController.GetBehaviours<ICollider2D>())
colliders.Add(collider2D);
rigidBody.BehaviourController.OnBehaviourAdded += OnBehaviourAdded;
rigidBody.BehaviourController.OnBehaviourRemoved += OnBehaviourRemoved;
}
public void RemoveRigidBody(IRigidBody2D rigidBody)
{
rigidBodies.Remove(rigidBody);
}
public void Step(float deltaTime)
{
float intervalDeltaTime = deltaTime / IterationCount;
for (int iterationIndex = 0; iterationIndex < IterationCount; iterationIndex++)
{
foreach (var rigidBody in rigidBodies)
StepRigidBody(rigidBody, intervalDeltaTime);
foreach (var collider in colliders)
collider.Recalculate();
}
}
private static void StepRigidBody(IRigidBody2D rigidBody, float intervalDeltaTime)
{
rigidBody.Transform.Position += rigidBody.Velocity * intervalDeltaTime;
rigidBody.Transform.Rotation += rigidBody.AngularVelocity * intervalDeltaTime;
}
private void OnBehaviourAdded(IBehaviourController controller, IBehaviour behaviour)
{
if (behaviour is not ICollider2D collider2D)
return;
colliders.Add(collider2D);
}
private void OnBehaviourRemoved(IBehaviourController controller, IBehaviour behaviour)
{
if (behaviour is not ICollider2D collider2D)
return;
colliders.Remove(collider2D);
}
}

View File

@ -0,0 +1,5 @@
using Syntriax.Engine.Physics2D.Abstract;
namespace Syntriax.Engine.Physics2D;
public record PhysicsMaterial2D(float Friction, float Restitution) : IPhysicsMaterial2D { }

View File

@ -0,0 +1,6 @@
namespace Syntriax.Engine.Physics2D;
public record PhysicsMaterial2DDefault : PhysicsMaterial2D
{
public PhysicsMaterial2DDefault() : base(.1f, .1f) { }
}

View File

@ -0,0 +1,118 @@
using System;
using System.Collections.Generic;
using Microsoft.Xna.Framework;
using Syntriax.Engine.Core;
using Syntriax.Engine.Physics2D.Primitives;
namespace Syntriax.Engine.Physics2D;
public static class PhysicsMath
{
public static Vector2D Scale(this Vector2D original, Vector2D scale)
=> new Vector2D(original.X * scale.X, original.Y * scale.Y);
public static Triangle ToSuperTriangle(this IList<Vector2D> vertices)
{
float minX = float.MaxValue, minY = float.MaxValue;
float maxX = float.MinValue, maxY = float.MinValue;
foreach (Vector2D point in vertices)
{
minX = MathF.Min(minX, point.X);
minY = MathF.Min(minY, point.Y);
maxX = MathF.Max(maxX, point.X);
maxY = MathF.Max(maxY, point.Y);
}
float dx = maxX - minX;
float dy = maxY - minY;
float deltaMax = MathF.Max(dx, dy);
float midX = (minX + maxX) / 2;
float midY = (minY + maxY) / 2;
Vector2D p1 = new Vector2D((float)midX - 20f * (float)deltaMax, (float)midY - (float)deltaMax);
Vector2D p2 = new Vector2D((float)midX, (float)midY + 20 * (float)deltaMax);
Vector2D p3 = new Vector2D((float)midX + 20 * (float)deltaMax, (float)midY - (float)deltaMax);
return new Triangle(p1, p2, p3);
}
public static IList<Line> ToLines(this IList<Vector2D> vertices)
{
List<Line> lines = new List<Line>(vertices.Count - 1);
ToLines(vertices, lines);
return lines;
}
public static void ToLines(this IList<Vector2D> vertices, IList<Line> lines)
{
lines.Clear();
for (int i = 0; i < vertices.Count - 1; i++)
lines.Add(new(vertices[i], vertices[i + 1]));
lines.Add(new(vertices[^1], vertices[0]));
}
public static bool LaysOn(this Vector2D point, Line line)
=> line.Resolve(point.X).ApproximatelyEquals(point);
// Given three collinear points p, q, r, the function checks if
// point q lies on line segment 'pr'
public static bool OnSegment(Vector2D p, Vector2D q, Vector2D r)
{
if (q.X <= MathF.Max(p.X, r.X) && q.X >= MathF.Min(p.X, r.X) &&
q.Y <= MathF.Max(p.Y, r.Y) && q.Y >= MathF.Min(p.Y, r.Y))
return true;
return false;
}
// To find orientation of ordered triplet (p, q, r).
// The function returns following values
// 0 --> p, q and r are collinear
// 1 --> Clockwise
// 2 --> Counterclockwise
public static int Orientation(Vector2D p, Vector2D q, Vector2D r)
{
// See https://www.geeksforgeeks.org/orientation-3-ordered-points/
// for details of below formula.
float val = (q.Y - p.Y) * (r.X - q.X) -
(q.X - p.X) * (r.Y - q.Y);
if (val == 0) return 0; // collinear
return (val > 0) ? 1 : 2; // clock or counterclock wise
}
public static float IntersectionParameterT(Vector2D p0, Vector2D p1, Vector2D q0, Vector2D q1)
=> ((q0.X - p0.X) * (p1.Y - p0.Y) - (q0.Y - p0.Y) * (p1.X - p0.X)) /
((q1.Y - q0.Y) * (p1.X - p0.X) - (q1.X - q0.X) * (p1.Y - p0.Y));
public static bool ApproximatelyEquals(this float a, float b)
=> ApproximatelyEquals(a, b, float.Epsilon);
public static bool ApproximatelyEquals(this Vector2 a, Vector2 b)
=> ApproximatelyEquals(a, b, float.Epsilon);
public static bool ApproximatelyEquals(this Vector2 a, Vector2 b, float epsilon)
=> ApproximatelyEquals(a.X, b.X, epsilon) && ApproximatelyEquals(a.Y, b.Y, epsilon);
public static bool ApproximatelyEquals(this Vector2D a, Vector2D b)
=> ApproximatelyEquals(a, b, float.Epsilon);
public static bool ApproximatelyEquals(this Vector2D a, Vector2D b, float epsilon)
=> ApproximatelyEquals(a.X, b.X, epsilon) && ApproximatelyEquals(a.Y, b.Y, epsilon);
public static bool ApproximatelyEquals(this float a, float b, float epsilon)
{
if (a == b)
return true;
const float floatNormal = (1 << 23) * float.Epsilon;
float absA = MathF.Abs(a);
float absB = MathF.Abs(b);
float diff = MathF.Abs(a - b);
if (a == 0.0f || b == 0.0f || diff < floatNormal)
return diff < (epsilon * floatNormal);
return diff / MathF.Min(absA + absB, float.MaxValue) < epsilon;
}
}

View File

@ -0,0 +1,17 @@
using Syntriax.Engine.Core;
namespace Syntriax.Engine.Physics2D.Primitives;
public record AABB(Vector2D LowerBoundary, Vector2D UpperBoundary)
{
public bool Overlaps(Vector2D point)
=> point.X >= LowerBoundary.X && point.X <= UpperBoundary.X &&
point.Y >= LowerBoundary.Y && point.Y <= UpperBoundary.Y;
public bool Overlaps(AABB other)
=> LowerBoundary.X <= other.UpperBoundary.X && UpperBoundary.X >= other.LowerBoundary.X &&
LowerBoundary.Y <= other.UpperBoundary.Y && UpperBoundary.Y >= other.LowerBoundary.Y;
public bool ApproximatelyEquals(AABB other)
=> LowerBoundary.ApproximatelyEquals(other.LowerBoundary) && UpperBoundary.ApproximatelyEquals(other.UpperBoundary);
}

View File

@ -0,0 +1,18 @@
using Syntriax.Engine.Core;
namespace Syntriax.Engine.Physics2D.Primitives;
public record Circle(Vector2D Position, float Radius)
{
public bool Intersects(Circle other)
{
float distanceSquared = (Position - other.Position).LengthSquared();
float radiusSumSquared = Radius * Radius + other.Radius * other.Radius;
return distanceSquared < radiusSumSquared;
}
public bool Overlaps(Vector2D point) => (Position - point).LengthSquared() <= Radius * Radius;
public bool ApproximatelyEquals(Circle other)
=> Position.ApproximatelyEquals(other.Position) && Radius.ApproximatelyEquals(other.Radius);
}

View File

@ -0,0 +1,146 @@
using System;
using System.Collections.Generic;
using System.Diagnostics.CodeAnalysis;
using Syntriax.Engine.Core;
namespace Syntriax.Engine.Physics2D.Primitives;
public record Line(Vector2D From, Vector2D To)
{
public Line Reversed => new(To, From);
public Vector2D Direction => Vector2D.Normalize(To - From);
public float Length => (From - To).Length();
public float LengthSquared => (From - To).LengthSquared();
public LineEquation LineEquation
{
get
{
Vector2D slopeVector = To - From;
float slope = slopeVector.Y / slopeVector.X;
float yOffset = From.Y - (slope * From.X);
return new LineEquation(slope, yOffset);
}
}
public bool Intersects(Vector2D point)
=> Resolve(point.X).ApproximatelyEquals(point);
public float GetT(Vector2D point)
{
float fromX = MathF.Abs(From.X);
float toX = MathF.Abs(To.X);
float pointX = MathF.Abs(point.X);
float min = MathF.Min(fromX, toX);
float max = MathF.Max(fromX, toX) - min;
pointX -= min;
float t = pointX / max;
// FIXME
// I don't even know, apparently whatever I wrote up there doesn't take into account of the direction of the line
// Which... I can see how, but I am also not sure how I can make it take into account. Or actually I'm for some reason
// too unmotivated to find a solution. Future me, find a better way if possible, please.
if (!Lerp(t).ApproximatelyEquals(point))
return 1f - t;
return t;
}
public bool Exist(List<Vector2D> vertices)
{
for (int i = 0; i < vertices.Count - 1; i++)
{
Vector2D vertexCurrent = vertices[i];
Vector2D vertexNext = vertices[i];
if (From == vertexCurrent && To == vertexNext) return true;
if (From == vertexNext && To == vertexCurrent) return true;
}
Vector2D vertexFirst = vertices[0];
Vector2D vertexLast = vertices[^1];
if (From == vertexFirst && To == vertexLast) return true;
if (From == vertexLast && To == vertexFirst) return true;
return false;
}
public float IntersectionParameterT(Line other)
{
float numerator = (From.X - other.From.X) * (other.From.Y - other.To.Y) - (From.Y - other.From.Y) * (other.From.X - other.To.X);
float denominator = (From.X - To.X) * (other.From.Y - other.To.Y) - (From.Y - To.Y) * (other.From.X - other.To.X);
// Lines are parallel
if (denominator == 0)
return float.NaN;
return numerator / denominator;
}
public Vector2D Lerp(float t)
=> new Vector2D(
From.X + (To.X - From.X) * t,
From.Y + (To.Y - From.Y) * t
);
public Vector2D Resolve(float x)
=> new Vector2D(x, LineEquation.Resolve(x));
public Vector2D ClosestPointTo(Vector2D point)
{
// Convert edge points to vectors
var edgeVector = new Vector2D(To.X - From.X, To.Y - From.Y);
var pointVector = new Vector2D(point.X - From.X, point.Y - From.Y);
// Calculate the projection of pointVector onto edgeVector
float t = (pointVector.X * edgeVector.X + pointVector.Y * edgeVector.Y) / (edgeVector.X * edgeVector.X + edgeVector.Y * edgeVector.Y);
// Clamp t to the range [0, 1] to ensure the closest point is on the edge
t = MathF.Max(0, MathF.Min(1, t));
// Calculate the closest point on the edge
float closestX = From.X + t * edgeVector.X;
float closestY = From.Y + t * edgeVector.Y;
return new Vector2D((float)closestX, (float)closestY);
}
public Vector2D IntersectionPoint(Line other)
=> Vector2D.Lerp(From, To, IntersectionParameterT(other));
public bool Intersects(Line other)
{
int o1 = PhysicsMath.Orientation(From, To, other.From);
int o2 = PhysicsMath.Orientation(From, To, other.To);
int o3 = PhysicsMath.Orientation(other.From, other.To, From);
int o4 = PhysicsMath.Orientation(other.From, other.To, To);
if (o1 != o2 && o3 != o4)
return true;
if (o1 == 0 && PhysicsMath.OnSegment(From, other.From, To)) return true;
if (o2 == 0 && PhysicsMath.OnSegment(From, other.To, To)) return true;
if (o3 == 0 && PhysicsMath.OnSegment(other.From, From, other.To)) return true;
if (o4 == 0 && PhysicsMath.OnSegment(other.From, To, other.To)) return true;
return false;
}
public bool Intersects(Line other, [NotNullWhen(returnValue: true)] out Vector2D? point)
{
point = null;
bool result = Intersects(other);
if (result)
point = IntersectionPoint(other);
return result;
}
public bool ApproximatelyEquals(Line other)
=> From.ApproximatelyEquals(other.From) && To.ApproximatelyEquals(other.To);
}

View File

@ -0,0 +1,8 @@
namespace Syntriax.Engine.Physics2D.Primitives;
public record LineEquation(float Slope, float OffsetY)
{
public float Resolve(float x) => Slope * x + OffsetY; // y = mx + b
public bool ApproximatelyEquals(LineEquation other)
=> Slope.ApproximatelyEquals(other.Slope) && OffsetY.ApproximatelyEquals(other.OffsetY);
}

View File

@ -0,0 +1,9 @@
namespace Syntriax.Engine.Physics2D.Primitives;
public static class Math
{
public const float RadianToDegree = 57.29577866666166f;
public const float DegreeToRadian = 0.01745329277777778f;
public static float Clamp(float value, float min, float max) => (value < min) ? min : (value > max) ? max : value;
}

View File

@ -0,0 +1,68 @@
using System;
using System.Collections.Generic;
using Syntriax.Engine.Core;
namespace Syntriax.Engine.Physics2D.Primitives;
public record Shape(IList<Vector2D> Vertices)
{
public Triangle SuperTriangle
{
get
{
float minX = float.MaxValue, minY = float.MaxValue;
float maxX = float.MinValue, maxY = float.MinValue;
foreach (Vector2D point in Vertices)
{
minX = MathF.Min(minX, point.X);
minY = MathF.Min(minY, point.Y);
maxX = MathF.Max(maxX, point.X);
maxY = MathF.Max(maxY, point.Y);
}
float dx = maxX - minX;
float dy = maxY - minY;
float deltaMax = MathF.Max(dx, dy);
float midX = (minX + maxX) / 2;
float midY = (minY + maxY) / 2;
Vector2D p1 = new Vector2D((float)midX - 20f * (float)deltaMax, (float)midY - (float)deltaMax);
Vector2D p2 = new Vector2D((float)midX, (float)midY + 20 * (float)deltaMax);
Vector2D p3 = new Vector2D((float)midX + 20 * (float)deltaMax, (float)midY - (float)deltaMax);
return new Triangle(p1, p2, p3);
}
}
public List<Line> Lines
{
get
{
List<Line> lines = new List<Line>(Vertices.Count - 1);
GetLinesNonAlloc(lines);
return lines;
}
}
public void GetLinesNonAlloc(IList<Line> lines)
{
lines.Clear();
for (int i = 0; i < Vertices.Count - 1; i++)
lines.Add(new(Vertices[i], Vertices[i + 1]));
lines.Add(new(Vertices[^1], Vertices[0]));
}
public bool ApproximatelyEquals(Shape other)
{
if (Vertices.Count != other.Vertices.Count)
return false;
for (int i = 0; i < Vertices.Count; i++)
if (!Vertices[i].ApproximatelyEquals(other.Vertices[i]))
return false;
return true;
}
}

View File

@ -0,0 +1,54 @@
using System;
using Syntriax.Engine.Core;
namespace Syntriax.Engine.Physics2D.Primitives;
public record Triangle(Vector2D A, Vector2D B, Vector2D C)
{
public float Area => MathF.Abs((
A.X * (B.Y - C.Y) +
B.X * (C.Y - A.Y) +
C.X * (A.Y - B.Y)
) * .5f);
public Circle CircumCircle
{
get
{
Vector2D midAB = (A + B) / 2;
Vector2D midBC = (B + C) / 2;
float slopeAB = (B.Y - A.Y) / (B.X - A.X);
float slopeBC = (C.Y - B.Y) / (C.X - B.X);
Vector2D center;
if (MathF.Abs(slopeAB - slopeBC) > float.Epsilon)
{
float x = (slopeAB * slopeBC * (A.Y - C.Y) + slopeBC * (A.X + B.X) - slopeAB * (B.X + C.X)) / (2 * (slopeBC - slopeAB));
float y = -(x - (A.X + B.X) / 2) / slopeAB + (A.Y + B.Y) / 2;
center = new Vector2D(x, y);
}
else
center = (midAB + midBC) * .5f;
return new(center, Vector2D.Distance(center, A));
}
}
public bool Overlaps(Vector2D point)
{
float originalTriangleArea = Area;
float pointTriangleArea1 = new Triangle(point, B, C).Area;
float pointTriangleArea2 = new Triangle(A, point, C).Area;
float pointTriangleArea3 = new Triangle(A, B, point).Area;
float pointTriangleAreasSum = pointTriangleArea1 + pointTriangleArea2 + pointTriangleArea3;
return originalTriangleArea.ApproximatelyEquals(pointTriangleAreasSum, float.Epsilon * 3f);
}
public bool ApproximatelyEquals(Triangle other)
=> A.ApproximatelyEquals(other.A) && B.ApproximatelyEquals(other.B) && C.ApproximatelyEquals(other.C);
}

View File

@ -0,0 +1,24 @@
using System;
using Syntriax.Engine.Core;
using Syntriax.Engine.Core.Abstract;
using Syntriax.Engine.Physics2D.Abstract;
namespace Syntriax.Engine.Physics2D;
public class RigidBody2D : BehaviourOverride, IRigidBody2D
{
public Action<IAssignableTransform>? OnTransformAssigned { get => GameObject.OnTransformAssigned; set => GameObject.OnTransformAssigned = value; }
public IPhysicsMaterial2D Material { get; set; } = new PhysicsMaterial2DDefault();
public Vector2D Velocity { get; set; } = Vector2D.Zero;
public float AngularVelocity { get; set; } = 0f;
public float Mass { get; set; } = 0f;
ITransform IAssignableTransform.Transform => Transform;
public bool Assign(ITransform transform) => GameObject.Assign(transform);
}

View File

@ -7,6 +7,8 @@ Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Engine.Core", "Engine.Core\
EndProject EndProject
Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Engine.Input", "Engine.Input\Engine.Input.csproj", "{12149E55-1EE8-45B4-A82E-15BA981B0C6A}" Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Engine.Input", "Engine.Input\Engine.Input.csproj", "{12149E55-1EE8-45B4-A82E-15BA981B0C6A}"
EndProject EndProject
Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Engine.Physics2D", "Engine.Physics2D\Engine.Physics2D.csproj", "{3B3C3332-07E3-4A00-9898-0A5410BCB08C}"
EndProject
Global Global
GlobalSection(SolutionConfigurationPlatforms) = preSolution GlobalSection(SolutionConfigurationPlatforms) = preSolution
Debug|Any CPU = Debug|Any CPU Debug|Any CPU = Debug|Any CPU
@ -24,5 +26,9 @@ Global
{12149E55-1EE8-45B4-A82E-15BA981B0C6A}.Debug|Any CPU.Build.0 = Debug|Any CPU {12149E55-1EE8-45B4-A82E-15BA981B0C6A}.Debug|Any CPU.Build.0 = Debug|Any CPU
{12149E55-1EE8-45B4-A82E-15BA981B0C6A}.Release|Any CPU.ActiveCfg = Release|Any CPU {12149E55-1EE8-45B4-A82E-15BA981B0C6A}.Release|Any CPU.ActiveCfg = Release|Any CPU
{12149E55-1EE8-45B4-A82E-15BA981B0C6A}.Release|Any CPU.Build.0 = Release|Any CPU {12149E55-1EE8-45B4-A82E-15BA981B0C6A}.Release|Any CPU.Build.0 = Release|Any CPU
{3B3C3332-07E3-4A00-9898-0A5410BCB08C}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
{3B3C3332-07E3-4A00-9898-0A5410BCB08C}.Debug|Any CPU.Build.0 = Debug|Any CPU
{3B3C3332-07E3-4A00-9898-0A5410BCB08C}.Release|Any CPU.ActiveCfg = Release|Any CPU
{3B3C3332-07E3-4A00-9898-0A5410BCB08C}.Release|Any CPU.Build.0 = Release|Any CPU
EndGlobalSection EndGlobalSection
EndGlobal EndGlobal