HerculesImage.mesa (pieces of JunoStorage.mesa), coded June 81 by Greg Nelson.

The current (unnamed) image and related procedures

Last Edited by: GNelson, September 14, 1982 4: 38 pm

Last Edited by: Stolfi, February 22, 1984 5:49 am

DIRECTORY
Rope,
HerculesStorage,
HerculesAlgebra USING[Frame, Matrix];

HerculesImage: DEFINITIONS =

BEGIN OPEN HerculesStorage, Alg: HerculesAlgebra;

- - - - THE CURRENT IMAGE

image: Image; -- The current image

AddPoint: PROC [p: PointPtr];
-- Adds the given point to the image, in proper x-order

SortPoints: PROC;
-- Sorts list of points points by increasing x-coordinate.
-- Useful after moves and constraint solving.

AddConstr: PROC [c: ConstrPtr];
-- Adds the given constraint to the image.

AddAction: PROC [a: ActionPtr];
-- Adds the given action to the image (in chronological order).

- - - - IMAGE SAVE AND RESTORE

PushImage: PROC;
-- saves current image (i.e., its points, constraints, and actions) and makes it empty

PopImage: PROC;
-- restores last saved image

PurgeImage: PROC;
-- makes current image to be empty

- - - - IMAGE ELEMENT ENUMERATION

PointOp: TYPE = PROC [p, pAnt: PointPtr];

EnumeratePoints: PROC [Op: PointOp];

ConstrOp: TYPE = PROC [c, cAnt: ConstrPtr];

EnumerateConstrs: PROC [Op: ConstrOp];

ActionOp: TYPE = PROC [a, aAnt: ActionPtr];

EnumerateActions: PROC [Op: ActionOp];

- - - - POINT LOCATION

FindPoint: PROC [x, y: REAL, wound: BOOL ← FALSE] RETURNS [champ: PointPtr];
-- This procedure finds the point closest to x, y in the current image.
-- If wound=TRUE then considers only points with non-zero winding number.

- - - - BALOON SELECTION

NextPointProc: TYPE = PROC RETURNS [x, y: INTEGER, lastPoint: BOOL];

BaloonSelect: PROC [xS, yS: INTEGER, NextPoint: NextPointProc];
-- The effect of BaloonSelect is to collect the vertices of a polygon
-- (starting with xS, yS and continuing as specified by the NextPoint procedure),
-- and set the wn (winding number)
-- field for all image points contained in the polygon.
-- The NextPoint procedure should return lastPoint = TRUE if x, y is the last point.
-- (BaloonSelect will close the polygon automatically)

AnyWoundPoints: PROC RETURNS [BOOL];
-- Returns TRUE if there are any points in the image with nonzero winding number.

- - - - OPERATIONS ON BALOON-SELECTED ITEMS

ConstrIsWound: PROC [c: ConstrPtr] RETURNS [wound: BOOL];
-- Returns TRUE if all points entering into the constraint c have wn # 0.

ActionIsWound: PROC [a: ActionPtr] RETURNS [wound: BOOL];
-- Returns TRUE if all points athat are arguments to the action a have wn # 0.

UnwindAllPoints: PROC;
-- Sets p.wn=0 for all points p in the image.

DeleteWoundItems: PROC;
-- Deletes all points with wn # 0 (unless connected by actions/constraints to unwound points).
-- Deletes also all actions and constraints involving only wound points.
-- After the call all points have wn=0.

TransformWoundPoints: PROC[mat: REF Alg.Matrix];
-- Applies the given transformation to all points p with p.wn#0.

MoveWoundPoints: PROC [source, dest: Alg.Frame] RETURNS [singular: BOOL];
-- This procedure assumes source and dest are frames with same number of points. It
-- (a) computes a transform that takes the source frame to the destination frame,
-- (b) applies the transform to all points with wn#0, and
-- (c) identifies the source points with the dest points (i.e. replaces the former by the latter
-- in all constraints and actions of the current image).
-- This procedure assumes all copy links are NIL on entry, all points in the source frame
-- have wn#0, and all points in the dest frame have wn=0.
-- It returns singular = TRUE if the source frame is degenerate.

CopyWoundItems: PROC;
-- Creates a new copy of every point p with p.wn#0.
-- Also creates a new copy of any constraint all of whose arguments have been copied.
-- After the call every copied point has p.copy pointing to its copy, p.wn set to zero, and
-- p.copy.wn set to the original p.wn.

IdentifyPoints: PROC;
-- For every point p such that p.copy#NIL, replaces p by p.copy
-- in all constraints and actions. Then sets
-- Also sets p.copy ← NIL for all points p in the image

END.

Edited on February 4, 1984 4:23 am, by Stolfi

Edited on February 6, 1984 7:19 pm, by Stolfi

Edited on February 8, 1984 6:11 pm, by Stolfi