DIRECTORY CoordSys, GraphicsColor, Matrix3d, Rope, Shading, SVBoundBox, SV2d, SVArtwork, SVVector3d; CSG: DEFINITIONS = BEGIN Artwork: TYPE = REF ArtworkObj; ArtworkObj: TYPE = SVArtwork.ArtworkObj; BoundBox: TYPE = SVBoundBox.BoundBox; BoundHedron: TYPE = SVBoundBox.BoundHedron; Color: TYPE = GraphicsColor.Color; CoordSystem: TYPE = CoordSys.CoordSystem; Matrix4by4: TYPE = Matrix3d.Matrix4by4; Point2d: TYPE = SV2d.Point2d; Point3d: TYPE = Matrix3d.Point3d; Vector: TYPE = SVVector3d.Vector; Surface: TYPE = REF ANY;-- may be RectSurface, TubeSurface, DiskSurface, ShellSurface... LightSourceList: TYPE = Shading.LightSourceList; RayCastProc: TYPE = PROC [cameraPoint: Point2d, localRay: Ray, masterObject: REF ANY, prim: Primitive] RETURNS [class: Classification]; RayCastNoBBoxesProc: TYPE = PROC [localRay: Ray, masterObject: REF ANY, prim: Primitive] RETURNS [class: Classification]; Classification: TYPE = REF ClassificationObj; ClassificationObj: TYPE = RECORD [ count: NAT, params: ParameterArray, surfaces: SurfaceArray, primitives: PrimitiveArray,-- the primitive from which each surface came classifs: InOutArray, normals: NormalArray]; maxSceneDepth: NAT = 40; ParameterArray: TYPE = ARRAY [1..maxSceneDepth] OF REAL; InOutArray: TYPE = ARRAY [1..maxSceneDepth] OF BOOL; NormalArray: TYPE = ARRAY [1..maxSceneDepth] OF Vector; SurfaceArray: TYPE = REF SurfaceArrayObj; SurfaceArrayObj: TYPE = ARRAY [1..maxSceneDepth] OF Surface; PrimitiveArray: TYPE = ARRAY [1..maxSceneDepth] OF Primitive; Primitive: TYPE = REF PrimitiveObj; PrimitiveObj: TYPE = RECORD [ name: Rope.ROPE, artwork: Artwork, assembly: REF ANY, -- a DisplayList3d.Assembly. REF ANY avoids compilation dependencies. mo: REF ANY, -- should be MasterObject but oh the compilation dependencies! rayCast: RayCastProc, rayCastNoBBoxes: RayCastNoBBoxesProc, primWRTAssembly: CoordSystem, scalars: Vector, worldWRTPrim: Matrix4by4, primWRTWorld: Matrix4by4, hints: REF ANY, -- each object type may wish to store helpful information here boundBox: BoundBox, boundHedron: BoundHedron, inverted: BOOL, -- is this shape to be subtracted? currentRay: Ray, rayStepX: Ray]; Ray: TYPE = REF RayObj; RayObj: TYPE = RECORD [ basePt: Point3d, direction: Vector]; PointSetOp: TYPE = {union, intersection, difference}; Composite: TYPE = REF CompositeObj; CompositeObj: TYPE = RECORD [ name: Rope.ROPE, operation: PointSetOp, leftSolid: REF ANY, rightSolid: REF ANY, boundBox: BoundBox]; CSGTree: TYPE = REF CSGTreeObj; CSGTreeObj: TYPE = RECORD [ name: Rope.ROPE, son: REF ANY, backgroundColor: Color, shadows: BOOL]; CopyClass: PROC [class: Classification] RETURNS [copy: Classification]; MakeCompositeCell: PROC [name: Rope.ROPE, operation: PointSetOp, LeftSolidPtr: REF ANY, RightSolidPtr: REF ANY] RETURNS [c: Composite]; MakeCSGTree: PROC [son: REF ANY, backgroundColor: Color, shadows: BOOL] RETURNS [tree: CSGTree]; CombineBoundBoxes: PROC [bb1, bb2: BoundBox, op: PointSetOp] RETURNS [newBB: BoundBox]; END. HFile: CSG.mesa Author: Eric Bier in the summer of 1982 Last edited by Bier on August 18, 1983 11:28 am Contents: The csg Solids Interface. Essentially maintains a database of csg trees each of which contains one or more combined primitives. Maintaining a tree involves creating primitives and adding them to trees with the csg operations, intersection, union, and difference. In my current plan, all of the instances of each surface type will refer to the same underlying csg surface expressed in the instance (unit dimensions) coordinate system. Hence, I will build these primitve shapes into the code (this more or less must be done anyway because the formulas - x^2 + y^2 = R^2; z = constant, etc. - are hard to enter symbolically in Mesa). However, for rapid rendering, I will have a line-drawing approximation to each world surface. These will involve a sweep-based representation with a finite mesh (translational sweep for blocks, rotational for cylinders and spheres). I will create one such representation for each of the primitive solid types in the same instance coordinate system in which the exact csg reps are defined. Rendering line-drawings with the sweep reps will then involve, using the same matrix transforms as are used to place the csg shapes, followed by a perspective transform and a call to 2d graphics routines. Э╩ЗЦ "cedar" styleШIheadЪЬЩIprocЪЬ'Щ'LЪЬ/Щ/LЪЬУЩУLШЪ╧k Ш LЪЬ Ш LЪЬШLЪЬ Ш LЪЬШLЪЬШLЪЬШLЪЬШLЪЬ Ш LЪЬШЧLШLЪЭЬЭЬШLЪЭШШLЪЬ ЭЬЭЬШLЪЬЭЬШ(LЪЬ ЭЬШ%LЪЬ ЭЬШ+LЪЬЭЬШ"LЪЬ ЭЬШ)LЪЬЭЬШ'LЪЬ ЭЬШLЪЬ ЭЬШ!LЪЬЭЬШ!LЪЬ ЭЬЭЬЭЬ╧c@ШXLЪЬЭЬШ0LЪ╧nЬЭЬЭЬ5ЭЬЭЬЭЬШЗLЪЯЬЭЬЭЬЭЬЭЬЭЬШyLШLЪЬЭЬЭЬШ-LЪЬЭЬЭЬШ"LЪЬЭЬШLЪЬШLЪЬШLЪЬЮ-ШHLЪЬШLЪЬШLШLЪЬЭЬШLЪ ЬЭЬЭЬЭЬЭЬШ8LЪ ЬЭЬЭЬЭЬЭЬШ4LЪЬ ЭЬЭЬЭЬШ7LЪЬЭЬЭЬШ)LЪЬЭЬЭЬЭЬ ШШKLЪЬШLШ%LЪЬШLЪЬШLЪЬШLЪЬШLЪЬЭЬЭЬЮ>ШNLЪЬШLЪЬШLЪЬ ЭЬЮ"Ш2LЪЬШLЪЬШLШЧLЪЬЭЬЭЬШLЪЬЭЬЭЬШLЪЬШLЪЬШLШLЪЬЁЩЁLЪЬ╘Щ╘LШLШLЪЬЭЬ%Ш5LШLЪЬЭЬЭЬШ#ЪЬЭЬЭЬШLЪЬЭЬШLЪЬШLЪЬЭЬЭЬШLЪЬЭЬЭЬШLЪЬШЧLШLЪЬ ЭЬЭЬШЪЬЭЬЭЬШLЪЬЭЬШLЪЬЭЬЭЬШ LЪЬШLЪЬ ЭЬШЧLШLШLЪЯ ЬЭЬЭЬШHLЪЯЬЭЬ ЭЬ'ЭЬЭЬЭЬЭЬЭЬШЗLШLЪЯЬЭЬЭЬЭЬ#ЭЬЭЬШaLЪЯЬЭЬ&ЭЬШWLШЧLЪЭЬШЧЕЧ╢Е