这个例子是参照Processing中的例子写的。

测试结果：在Windows7上，脱离开发环境的性能与Processing相当，在Android上表现良好。

源码如下：

unit Example.Particles;
 
 interface
 
 uses
 System.SysUtils, System.Types, System.UITypes, System.Classes, System.Variants,
 System.Generics.Collections, System.UIConsts,
 FMX.Types, FMX.Graphics, FMX.Controls, FMX.PixelFormats;
 
 type
 
 TParticle = class
 private
 FGravity: TPointF;
 FVelocity: TPointF;
 FLifeSpan: Integer;
 
 FPart: TBitmap;
 FPartSize: Integer;
 FPosition: TPointF;
 public
 constructor Create(ASprite: TBitmap; X, Y: Single);
 destructor Destroy(); override;
 procedure Rebirth(X, Y: Single);
 function IsDead(): Boolean;
 procedure Update(Canvas: TCanvas);
 end;
 
 TParticleSystem = class
 private
 FParticles: TObjectList 
                                  
                                    ; 
                                   
 public 
 constructor Create(Count: Integer; ASprite: TBitmap; X, Y: Single); 
 
 procedure Update(Canvas: TCanvas); 
 procedure SetEmmitter(X, Y: Single); 
 end; 
 
 implementation 
 
 
 { TParticle } 
 
 constructor TParticle.Create(ASprite: TBitmap; X, Y: Single); 
 begin 
 FGravity := TPointF.Create(0, 0.1); 
 FPartSize := Random(50) + 10; 
 FPart := ASprite; 
 Rebirth(X, Y); 
 FLifeSpan := Random(255); 
 end; 
 
 destructor TParticle.Destroy; 
 begin 
 //FPart.Free; 
 inherited; 
 end; 
 
 function TParticle.IsDead: Boolean; 
 begin 
 Result := (FLifeSpan <= 0); 
 end; 
 
 procedure TParticle.Rebirth(X, Y: Single); 
 var 
 Alpha: Single; 
 Speed: Single; 
 begin 
 Alpha := Random() * 2 * PI; 
 Speed := Random() * 4 + 0.5; 
 FVelocity := TPointf.Create(Cos(Alpha), Sin(Alpha)); 
 FVelocity := FVelocity * Speed; 
 FLifeSpan := Random(100) + 155; 
 FPosition := TPointF.Create(X, Y); 
 end; 
 
 procedure TParticle.Update(Canvas: TCanvas); 
 begin 
 FLifeSpan := FLifeSpan - 1; 
 FVelocity.Offset(FGravity); 
 FPosition := FPosition + FVelocity; 
 
 Canvas.DrawBitmap(FPart, 
 RectF(0, 0, FPart.Width, FPart.Height), 
 RectF(FPosition.X, FPosition.Y, 
 FPosition.X + FPartSize, FPosition.Y + FPartSize), 
 FLifeSpan, True); 
 end; 
 
 { TParticleSystem } 
 
 constructor TParticleSystem.Create(Count: Integer; ASprite: TBitmap; X, Y: Single); 
 var 
 I: Integer; 
 begin 
 FParticles := TObjectList 
                                                                                                    
                                                                                                      .Create(True); 
                                                                                                     
 for I := 0 to Count - 1 do 
 FParticles.Add(TParticle.Create(ASprite, X, Y)); 
 end; 
 
 procedure TParticleSystem.SetEmmitter(X, Y: Single); 
 var 
 Part: TParticle; 
 begin 
 for Part in FParticles do 
 if Part.IsDead then 
 Part.Rebirth(X, Y); 
 end; 
 
 procedure TParticleSystem.Update(Canvas: TCanvas); 
 var 
 Part: TParticle; 
 begin 
 for Part in FParticles do 
 Part.Update(Canvas); 
 end; 
 
 end. 






















                                                                                                     

































































                                  

unit Example.ParticleMain;
 
 interface
 
 uses
 System.SysUtils, System.Types, System.UITypes, System.Classes, System.Variants,
 FMX.Types, FMX.Controls, FMX.Forms, FMX.Graphics, FMX.Dialogs, FMX.Objects,
 FMX.Edit, Example.Particles, FMX.MaterialSources;
 
 type
 TParticleForm = class(TForm)
 Timer1: TTimer;
 TextureMaterial: TTextureMaterialSource;
 procedure FormCreate(Sender: TObject);
 procedure FormDestroy(Sender: TObject);
 procedure FormPaint(Sender: TObject; Canvas: TCanvas; const ARect: TRectF);
 procedure Timer1Timer(Sender: TObject);
 private
 { Private declarations }
 FParticleSystem: TParticleSystem;
 FPS: Integer;
 procedure DoIdle(Sender: TObject; var Done: Boolean);
 public
 procedure Setup();
 procedure Loop();
 end;
 
 var
 ParticleForm: TParticleForm;
 
 implementation
 
 {$R *.fmx}
 
 procedure TParticleForm.DoIdle(Sender: TObject; var Done: Boolean);
 begin
 Invalidate();
 end;
 
 procedure TParticleForm.FormCreate(Sender: TObject);
 begin
 Setup();
 end;
 
 procedure TParticleForm.FormDestroy(Sender: TObject);
 begin
 FParticleSystem.Free;
 end;
 
 procedure TParticleForm.FormPaint(Sender: TObject; Canvas: TCanvas;
 const ARect: TRectF);
 begin
 Loop();
 end;
 
 procedure TParticleForm.Loop();
 var
 P: TPointF;
 begin
 Inc(FPS);
 P := ScreenToClient(Screen.MousePos);
 Canvas.BeginScene();
 Canvas.Clear($FF000000);
 Canvas.Fill.Color := $FFFFFFFF;
 Canvas.FillText(Rectf(0, 0, Width, Height), Caption, False,
 255, [], TTextAlign.taLeading, TTextAlign.taLeading);
 FParticleSystem.Update(Canvas);
 Canvas.Fill.Color := $FF000000;
 Canvas.FillText(RectF(0, 0, ClientWidth, ClientHeight), '2013 曹伟民 ', False,
 255, [], TTextAlign.taCenter, TTextAlign.taTrailing);
 Canvas.EndScene;
 FParticleSystem.SetEmmitter(P.X, P.Y);
 end;
 
 procedure TParticleForm.Setup;
 begin
 Randomize;
 Application.OnIdle := DoIdle;
 FParticleSystem := TParticleSystem.Create(10000, TextureMaterial.Texture,
 Width / 2, Height / 2);
 end;
 
 procedure TParticleForm.Timer1Timer(Sender: TObject);
 begin
 Caption := Format('Frames Per Second: %d', [FPS]);
 FPS := 0;
 end;
 
 end.

效果图：