Delphi/CppBuilder

开发平台：
Delphi

UCollisionFiltering.pas：源码内容
							unit UCollisionFiltering;
interface
{$I ......SourcePhysics2D.inc}
uses
   UMain, UPhysics2DTypes, UPhysics2D, SysUtils;
type
   TCollisionFiltering = class(TTester)
   public
      constructor Create; override;
   end;
implementation
const
   // This is a test of collision filtering.
   // There is a triangle, a box, and a circle.
   // There are 6 shapes. 3 large and 3 small.
   // The 3 small ones always collide.
   // The 3 large ones never collide.
   // The boxes don't collide with triangles (except if both are small).
   k_smallGroup = 1;
   k_largeGroup = -1;
   k_defaultCategory = $0001;
   k_triangleCategory = $0002;
   k_boxCategory = $0004;
   k_circleCategory = $0008;
   k_triangleMask = $FFFF;
   k_boxMask = $FFFF xor k_triangleCategory;
   k_circleMask = $FFFF;
{ TCollisionFiltering }
constructor TCollisionFiltering.Create;
var
   sd, boxShapeDef: Tb2PolygonDef;
   bd, triangleBodyDef, boxBodyDef, circleBodyDef: Tb2BodyDef;
   ground, body1, body2, body3, body4, body5, body6: Tb2Body;
   triangleShapeDef: Tb2PolygonDef;
   circleShapeDef: Tb2CircleDef;
begin
   inherited;
   // Ground body
   begin
      sd := Tb2PolygonDef.Create;
      sd.SetAsBox(50.0, 10.0);
      sd.friction := 0.3;
      bd := Tb2BodyDef.Create;
      {$IFDEF OP_OVERLOAD}
      bd.position.SetValue(0.0, -10.0);
      {$ELSE}
      SetValue(bd.position, 0.0, -10.0);
      {$ENDIF}
      ground := m_world.CreateBody(bd);
      ground.CreateShape(sd);
   end;
   // Small triangle
   triangleShapeDef := Tb2PolygonDef.Create;
   triangleShapeDef.vertexCount := 3;
   {$IFDEF OP_OVERLOAD}
   triangleShapeDef.vertices[0].SetValue(-1.0, 0.0);
   triangleShapeDef.vertices[1].SetValue(1.0, 0.0);
   triangleShapeDef.vertices[2].SetValue(0.0, 2.0);
   {$ELSE}
   SetValue(triangleShapeDef.vertices[0], -1.0, 0.0);
   SetValue(triangleShapeDef.vertices[1], 1.0, 0.0);
   SetValue(triangleShapeDef.vertices[2], 0.0, 2.0);
   {$ENDIF}
   triangleShapeDef.density := 1.0;
   triangleShapeDef.filter.groupIndex := k_smallGroup;
   triangleShapeDef.filter.categoryBits := k_triangleCategory;
   triangleShapeDef.filter.maskBits := k_triangleMask;
   triangleBodyDef := Tb2BodyDef.Create;
   {$IFDEF OP_OVERLOAD}
   triangleBodyDef.position.SetValue(-5.0, 2.0);
   {$ELSE}
   SetValue(triangleBodyDef.position, -5.0, 2.0);
   {$ENDIF}
   body1 := m_world.CreateBody(triangleBodyDef, False);
   body1.CreateShape(triangleShapeDef, False);
   body1.SetMassFromShapes;
   // Large triangle (recycle definitions)
   {$IFDEF OP_OVERLOAD}
   triangleShapeDef.vertices[0] := triangleShapeDef.vertices[0] * 2.0;
   triangleShapeDef.vertices[1] := triangleShapeDef.vertices[1] * 2.0;
   triangleShapeDef.vertices[2] := triangleShapeDef.vertices[2] * 2.0;
   {$ELSE}
   triangleShapeDef.vertices[0] := Multiply(triangleShapeDef.vertices[0], 2.0);
   triangleShapeDef.vertices[1] := Multiply(triangleShapeDef.vertices[1], 2.0);
   triangleShapeDef.vertices[2] := Multiply(triangleShapeDef.vertices[2], 2.0);
   {$ENDIF}
   triangleShapeDef.filter.groupIndex := k_largeGroup;
   {$IFDEF OP_OVERLOAD}
   triangleBodyDef.position.SetValue(-5.0, 6.0);
   {$ELSE}
   SetValue(triangleBodyDef.position, -5.0, 6.0);
   {$ENDIF}
   triangleBodyDef.fixedRotation := True; // look at me!
   body2 := m_world.CreateBody(triangleBodyDef);
   body2.CreateShape(triangleShapeDef);
   body2.SetMassFromShapes;
   // Small box
   boxShapeDef := Tb2PolygonDef.Create;
   boxShapeDef.SetAsBox(1.0, 0.5);
   boxShapeDef.density := 1.0;
   boxShapeDef.filter.groupIndex := k_smallGroup;
   boxShapeDef.filter.categoryBits := k_boxCategory;
   boxShapeDef.filter.maskBits := k_boxMask;
   boxBodyDef := Tb2BodyDef.Create;
   {$IFDEF OP_OVERLOAD}
   boxBodyDef.position.SetValue(0.0, 2.0);
   {$ELSE}
   SetValue(boxBodyDef.position, 0.0, 2.0);
   {$ENDIF}
   body3 := m_world.CreateBody(boxBodyDef, False);
   body3.CreateShape(boxShapeDef, False);
   body3.SetMassFromShapes;
   // Large box (recycle definitions)
   boxShapeDef.SetAsBox(2.0, 1.0);
   boxShapeDef.filter.groupIndex := k_largeGroup;
   {$IFDEF OP_OVERLOAD}
   boxBodyDef.position.SetValue(0.0, 6.0);
   {$ELSE}
   SetValue(boxBodyDef.position, 0.0, 6.0);
   {$ENDIF}
   body4 := m_world.CreateBody(boxBodyDef);
   body4.CreateShape(boxShapeDef);
   body4.SetMassFromShapes;
   // Small circle
   circleShapeDef := Tb2CircleDef.Create;
   circleShapeDef.radius := 1.0;
   circleShapeDef.density := 1.0;
   circleShapeDef.filter.groupIndex := k_smallGroup;
   circleShapeDef.filter.categoryBits := k_circleCategory;
   circleShapeDef.filter.maskBits := k_circleMask;
   circleBodyDef := Tb2BodyDef.Create;
   {$IFDEF OP_OVERLOAD}
   circleBodyDef.position.SetValue(5.0, 2.0);
   {$ELSE}
   SetValue(circleBodyDef.position, 5.0, 2.0);
   {$ENDIF}
   body5 := m_world.CreateBody(circleBodyDef, False);
   body5.CreateShape(circleShapeDef, False);
   body5.SetMassFromShapes;
   // Large circle
   circleShapeDef.radius :=  circleShapeDef.radius * 2.0;
   circleShapeDef.filter.groupIndex := k_largeGroup;
   {$IFDEF OP_OVERLOAD}
   circleBodyDef.position.SetValue(5.0, 6.0);
   {$ELSE}
   SetValue(circleBodyDef.position, 5.0, 6.0);
   {$ENDIF}
   body6 := m_world.CreateBody(circleBodyDef);
   body6.CreateShape(circleShapeDef);
   body6.SetMassFromShapes;
end;
initialization
   RegisterTestEntry('Collision Filtering', TCollisionFiltering);
end.

						