Plotting Method and Apparatus

This invention relates to fitting of material into areas of predetermined shape. While having broader applicability, the invention will be described in connection with fitting of roll goods such as carpet or linoleum into floor areas.

In estimating the amount of carpet needed to cover a given area, it is first necessary to measure the area. This is usually done by stretching a tape along each wall of the area to be carpeted and generating a rough diagram with each length along the perimeter dimensioned.

Having accomplished that, it is then necessary to "fit" the roll goods to the area, keeping in mind the factors of optimizing seam position (or at least avoiding improper seam locations) minimizing waste, and matching the pattern, if any. In the past this has been done "by hand" by an experienced estimator who works with pencil, scratch pad, and his experience, to attempt to determine how many yards of roll goods are necessary to complete the job and also how those roll goods should be cut and fit to install the job. If the estimator and the installer are different people, it is also necessary to provide some means of communicating the estimator's "game plan" to the installer.

As is appreciated by those skilled in this art, this practice is prone to introduction of errors, particularly in the case of inexperience estimators. If the error is on the high side, the result is the purchase of excess materials and the ill feeling on the part of the consumer that can create. If the error is on the short side, the result is often a job which cannot be installed in the first instance, or if installed improperly must later be removed and replaced at great expense to the carpet seller.

The need exists, especially in the case of high volume carpet or floor covering retailers, to eliminate to the greatest extent possible opportunities for introducing errors into this estimating practice. Assuming the relatively mechanical job of perimeter measuring can be accomplished, it would be highly desirable to assure that those measurements can be transformed, knowing the characteristics of the roll goods, into an accurate and efficient estimate of the needed material as well as a plan from which the installer can accurately cut and install the material in the required area.

In view of the foregoing, it is the general aim of the present invention to provide means for accurately transforming perimeter area measurements into a detailed plan from which roll goods can be cut and installed.

More particularly, it is an object of the present invention to provide means into which perimeter measurements can be entered, much as they are initially taken, along with information which characterizes the roll goods, such means being adapted to produce a foolproof and detailed layout from which the material can be cut and installed. A further object, in that regard, is to determine the dimensions of the goods needed to fit a particular layout.

It is an important but subsidiary object to provide such means which minimizes the amount of material required.

According to one aspect of the invention, it is an object to provide means which match scrap and destination areas to accurately and efficiently make use of carpeting which would otherwise be scrapped.

An additional object according to the present invention is to provide such means which takes into account the dimensional characteristics of any pattern in matching the material pattern from piece to piece.

According to another aspect of the invention, an object is to provide such a system which is interactive in that it accepts information from the user, then provides the user information which serves an aid in inputting further information to optimize the layout.

Other objects and advantages will become apparent from the following detailed description when taken in conjunction with the drawings in which:

FIG. 1 is a block diagram showing the interrelationship between the elements of an exemplary embodiment of the present invention;

FIGS. 2a-2e are flow charts illustrating a sequence of steps useful in practicing the present invention;

FIG. 3 is a typical layout plotted in accordance with the present invention;

FIG. 4 is another typical layout plotted in accordance with the present invention.

While the invention will be described in connection with a preferred embodiment, there is no intent to limit it to that embodiment. On the contrary, the intent is to cover all alternatives, modifications, and equivalents included within the spirit and scope of the invention as defined by the appended claims.

Turning now to the drawings, FIG. 1 shows, in block diagram form, a combination of elements useful in practicing the present invention and the relationship therebetween. More particularly, a central processor 20 has an associated program memory 21 conditioned by a sequence of steps (to be described below) to control certain aspects of the interactive method for fitting of material of predetermined dimensional characteristics into a given area. The central processor has circuit connections to an alpha/numeric keyboard 22 which provide one means for operator entry of information. Keystrokes on the keyboard 22 serve to transfer signals along a path schematically illustrated at 23 to cause the processor to perform desired functions. For providing temporary display of information under processor control, the system also includes a CRT display 24, having a schematically illustrated signal path 25 to the central processor.

In practicing the invention, a plotter 28 is provided which not only responds to signals from the processor 20 for making an appropriate diagram, but which also allows operator entry of data via the plotter to the central processor as a means of interactively generating the necessary layout. To that end, the plotter 28 has a pen 30 which can be driven by the central processor 20 by means of signals conveyed along the path schematically illustrated at 31, to move the pen and mark an associated paper with any desired pattern. In addition, the plotter 28 has a manual control 32, preferably in the form of a joystick which allows an operator to advance the pen 30 to any point on the platen of the plotter. For the purpose of conveying a signal from the plotter to the processor, a call button 33 is provided, which can be depressed by the operator after properly positioning the pen 30, and which results in the conveying of signals from the plotter to the processor identifying the pen location.

The separate signal paths 23, 25, 31 are intended to illustrate in schematic form the various paths for information exchange. In particular embodiments of the invention, such paths can be implemented by separate multi-conductor interface cables, or by arranging all of the units 21, 22, 24 and 28 to share a common data and address bus. The presently preferred embodiment of the invention implements the elements of FIG. 1 by way of the commercially available Tektronix 4051 Graphic System with 32k of memory (or the 4052 Graphic System with 64k of memory), used in conjunction with the 4622 Graphic Plotter.

Exhibit 1 which is attached at the end of this specification and made a part hereof is a source listing showing a preferred sequence of program steps capable of causing the aforementioned Tektronix Graphic System equipment to perform in accordance with the present invention. The reader is referred to the listing for the technical detail useful in practice of this invention. The following description will supplement such disclosure by first relating the manner in which an operator utilizes the graphic system to practice the invention, and secondly, by characterizing and generally describing modules of the program with reference to the flow charts of FIGS. 2a-2e.

Before proceeding to that description, however, it will be worthwhile to generally review the underlying philosophy by which an operator and the system interact in the practice of the present invention.

First of all, in order to fit roll goods into a given area, one must first know the shape and dimensions of the given area. While it is not overly difficult to estimate the amount of carpet required to cover a regular 9.times.12 room, if it is also desired to carpet the associated closet, the adjacent hallway, and perhaps another room, the problem becomes more complex. If the carpet has a pattern which must be matched throughout the installation, a further degree of difficulty is introduced. Whatever the situation, however, it is not unusual to start with a hand drawn sketch of the area to be covered, with a dimension associated with each line defining the perimeter.

In order to simplify communication of the area boundaries from the operator to the plotter device, the system is arranged to begin at a selected point, then accept signals relating to the dimensions of each boundary line, proceeding in sequence from the starting point around the periphery and typically returning to the starting point. The system is arranged to accept those signals in familiar units, such as feet and inches, to apply a desired scale factor (relating to the scale of the plot to be produced) and to create an array of signals stored to define the coordinates of the given area. In addition to accepting that input, the plotter is also operated to draw the outline being generated, which allows the operator to check the shape of the plot being produced against his original sketch. The plotted area not only shows the operator that he has correctly reproduced the sketch, but also serves to allow the operator to identify, on the drawings being produced, particular coordinates for specific purposes. For example, after the area is drawn, the operator is allowed to manually position the plotter pen, then to transmit a signal to the controller which serves to identify a selected seam line. Since the system had previously been provided a set of signals defining the dimensional characteristics of the roll goods, the plotter then operates to draw all seam lines within operator defined boundaries.

As a second example of operator interaction with the drawing being produced, the operator is afforded the ability to identify source locations, which would otherwise be removed for scrap, and to further identify selected destination locations where it is desired to utilize such scrap. The system is configured to select from the identified source, dimensional segments which are capable of fitting the destination, will full attention to pattern match. The plotter is then driven by the system to draw not only the destination areas to be covered from the source, but also the exact portions of the source area which are to be cut to fit those destinations.

As a final example of operator interaction with the plot being generated, the operator is afforded the ability to manipulate the plotter pen and produce signals for the system which identify the dimensions of particular carpet lengths. The system is configured to utilize that input in calculating the exact length for each strip, and for determining the order in which the strips are to be cut from the roll in ordr to minimize the amount of inter-strip waste.

With that general philosophy in mind, attention will now be directed to a typical sequence of operation from the point of view of the operator and the actions he witnesses the system taking during the course of producing a plot.

In order to assist the operator to the maximum extent possible, the system is configured to display prompting messages on the CRT, indicating the type of information desired at each point in the cycle. The message first displayed to the operator at the start of the cycle is "Enter Scale Factor". This provides the operator the ability to select the scale to which the plotter will draw the diagram. In the exemplary system the scale factor indicates the number of inches of the diagram which will represent one foot of the actual room's length or width. For an average residential layout, a scale factor of 0.150 inches per foot is often useful, whereas for larger commercial layouts, smaller scale factors might be required.

Having accepted the scale factor information, the system displays the following message: "Input Horizontal Dimension". In the exemplary embodiment, when this prompting request is first given, the plotter pen is in the lower lefthand corner of the diagram, and the information being requested is the length of the horizontal line which will form the base of the layout. The system is configured to accept the information in feet and inches separated by a comma. Momentary depression of the Return key after entry of the horizontal dimension causes the processor to accept related signals from the keyboard and store such signals in an array identifying the coordinates of the end points of the line just dimensioned.

Having entered the first horizontal dimension, the CRT is caused to display the following prompt "0=No Draw, 1=Draw, 2=Draw/Terminate". The operator selects one of the functions by typing the respective number thereof, followed by a momentary depression of the Return key. The No Draw instruction causes the plotter to reposition the pen at the end of the line whose dimension had been input without marking the paper. The Draw command causes a similar function, only with the pen in contact with the paper to make a horizontal line thereon scaled to the dimension just input. The Draw/Terminate command is used after the last dimensional entry, causing the program to advance to the next stage.

Assuming that either the No Draw or Draw commands have been given, the system, in addition to storing the signals described above and moving the pen, responds with the following prompt: "Input Vertical Dimension". Just as in the case of the horizontal entry, the dimension associated with the next line defining the periphery of the given area is entered in feet and inches. Following entry of the number, the system prompts with the "0=No Draw, 1=Draw, 2=Draw/Terminate" prompt.

The system continues to cycle between horizontal and vertical entries until the Draw/Terminate command is received. Any entry which would cause movement of the pen to the right or upwards on the diagram is considered a positive number and can be entered without sign. Any entry which would cause movement of the plotter pen to the left or downward on the diagram is considered a negative entry and must be preceded by a minus sign. As the plotter pen sequentially plots each boundary segment under the direction of the operator, he has the opportunity to roughly check the shape of the plot being generated against his original sketch. Entry of dimensional data related to the given area is then ended by answering the "0=No Draw, 1=Draw, 2=Draw/Terminate" prompt with a terminate command.

The system then sequences to the portion of the cycle which allows the operator to enter the dimensional characteristics of the material to be fit within the given area. The first prompt in this area of the sequence is "Horizontal Pattern Repeat (inches)." The information desired at this time is the horizontal repeat dimension of the material in inches. If the material to be fit in the given area has no pattern, a 0 is entered. If a number other than 0 were entered for the "Horizontal Pattern Repeat (inches)", the system responds by storing appropriate signals and displaying the following prompt: "Vertical Pattern Repeat (inches)". In response, the operator should input the vertical repeat dimension of the material in inches.

Following entry of the repeat dimensions, the system requests the following information: "Print Pattern Repeat (1=Yes, 0=No)." If Repeat dimensions were given, all of the system manipulations regarding fitting of the material into the given space will take account of the pattern. This prompt, however, simply asks whether the plot which is to be generated should have some indicia relating to the repeat pattern for further guidanace of the installer. A yes command will result in the printout of a dot pattern identifying points in the repeat pattern. A no response to this prompt will cause the system to be plotted without dots identifying the repeat pattern, but will still take account of the repeat pattern in fitting and estimating the material.

A further dimensional characteristic required of patterned materials is the information as to whether a drop pattern is involved. If adjacent patterns along the width of the material are aligned, the response to the prompt "Drop Pattern (1=Yes, 0=No)" is No. If, however, a drop pattern is involved, the response is Yes. The system responds by entering the associated information, then follows with the following prompt "Tackless (1=Yes, 0=No)." If the operator desires the system to determine the number of four foot tackless strips which will be required to install the job, he depresses the 1 key for an affirmative response. The final piece of information relating to dimensional characteristics of the material is provided in response to the prompt "Roll Width". The operator types in the roll width in feet which, when accepted by the processor, sequences to the next operation in which the operator is asked to manually manipulate the plotter to establish the first seam position. The prompt displayed to the operator is "Set Seam Position-Push Call."

In responding to this prompt, the operator makes use of the partly produced plot in selecting on the scaled layout a desired seam position. For example, if the base line or some other horizontal line on the plot is defined by a wall in the actual area, the operator might select that wall as the key seam line. Some other physical feature in the actual layout may cause the choice of some other position. At any rate, the operator uses the joystick on the plotter to advance the pen by any desired route to the point on the layout where he desires to set the first horizontal seam. When the pen is positioned in the proper location, the operator momentarily depresses the Call button on the plotter, which causes signals to be sent to the processor identifying the coordinates of the pen position. After the call button is momentarily depressed, the system then prompts "Input Low Left Boundary (Call)". The operator positions the pen in the region designating lower left corner of the area to be calculated, momentarily depresses the call button, which again causes signals to be sent to the processor identifying the coordinates of the pen position. Following this stage, the next prompt "Input High Right Boundary (Call)" appears, causing the operator to position pen to the uppermost right region of the specific area to be graphed with seams and pattern repeat points. This mode is repeated to allow for other seam locations not specified in the first boundaried area, and will advance to the succeeding mode when the call button is depressed three times without moving the plotter pen. The processor uses that information to establish a horizontal seam line at that location, and uses the previously entered roll width information to determine the location of all other seam lines within established boundaries.

Having received that information, the system then prompts as follows: "Enter C=Copy, M=Modify, R=Rotate, S=Scrap", which gives the operator four options. If on the one hand the operator determines from the information entered thus far that the layout is defective for some reason, he can enter an M command, which instructs the system that he desires to modify the layout, but without modifying the dimensions of the given area or the dimensional characteristics of the material. Typically this instruction is used when the operator is dissatisfied with seam positions and wishes to make a new selection. The program sequence, after reinitiating certain data arrays, reverts to the point at which the prompt "Set Seam Position-Push Call" is displayed. The sequence progresses as described above until the "Enter C=Copy, M=Modify, R=Rotate, S=Scrap" prompt is again displayed.

The Rotate command is useful when it is determined that it might be desirable to fit the roll goods not horizontally as the seams were previously drawn, but vertically. Since the system is configured to always "unroll" the goods horizontally, it is necessary to rotate the layout 90.degree.. That is accomplished by the Rotate command.

The Scrap command is useful in irregular layouts where material which might otherwise be discarded can be used to fill certain small areas. Depression of the S key to enter the scrap routine causes the system to display the prompt "Define Destination and Source (Call)". The operator is then afforded the opportunity to utilize the partially completed plot in entering additional information regarding source and destination for scrap use. The operator first identifies a destination area using the joystick and call button on the plotter, by identifying coordinates at opposed corners. The joystick is moved to one corner, the call button depressed to enter the coordinate, following which the opposite corner is identified.

Following the identification of the destination area, it is then necessary to identify the source area from which a piece corresponding in size and shape to the destination area will be taken. It is desirable to identify the largest source area possible, since the seam will only take the portion of the source necessary to fit the identified destination. As in the case of destination identification, the source is identified by manual manipulation of the plotter to identify opposed corners.

After the source is identified, the system will prompt the operator "New Destination (Y or N) (Call)". If there are further destination areas which can be filled from material available in the source, the operator enters Yes. If, on the other hand, the identified source area has been depleted, or if there are no new destination areas to be filled, the operator enters No, following which the system will determine the portion of the source needed to cover the destination, then plot both. Following that, the "Enter C=Copy, M=Modify, R=Rotate, S=Scrap" prompt is displayed, making any of the four options again available to the operator.

Ultimately the operator will be satisfied with the layout, and will indicate his acceptance by depressing the C key to enter the Copy command. The system will respond with the prompt "Select Dimensions Pickout Left (Call) Right (Call)". Again the operator is afforded the opportunity to utilize the partially completed plot to enter additional information, in this case signaling the length of each strip to the processor. That is accomplished by positioning the pen on the plotter using the joystick first at the left then at the right boundary of each strip, each position being signaled to the processor by momentary depression of the Call button. The pick-off exercise is terminated by a second and third depression of the call button after the last coordinate is entered and without moving the plotter pen.

The system has now been provided with all of the information necessary to complete the layout. It responds by completing the plot associating dimensions with each carpet length and by indicating the order in which the carpet lengths should be cut from the roll to minimize inter-length scrap.

Typical plotter drawings are illustrated in FIGS. 3 and 4 for two different floor plans. As there shown, each of the seam lines separating adjacent strips is identified. In FIG. 3, for example, seam 403 separates the large strip 407 from strip 401. The dashes collinear with seam 403 indicate the edge of the strips as cut from the original roll of material. FIG. 3 also shows the dot pattern generally designated 411 identifying pattern repeat points. The zigzag nature of the dots indicates that a drop pattern is involved. The tabulated information generally designated 413 at the right of the diagram illustrates both the total material length 415 and the total square yards 417 utilized. A price quote can be prepared directly from those figures. In addition, the pattern dimensional information including both the repeat dimension 419 and the roll width 421, is included. FIG. 3 also illustrates the use of scrap source and destination, with a source 423 identified on the plotter drawing by the drawn numeral 2. Its orientation is specified by a diagonal line beginning at upper left and running to lower right of the source rectangle 423. The associated destination is identified by destination rectangle 405 with the same drawn numeral 2, and a diagonal line joining the lower left and upper right corners. Thus the slant of the diagonal line discriminates between the source and destination. As best shown in FIG. 4, the drawn numeral adjacent each strip identifies the strip, whereas the length of each strip is indicated in a table generally designated 431 to the right of the strips, the sequence in the table indicating the order in which the strips are to be cut from the roll in order to minimize waste. The pattern of FIG. 3, in contrast, requires just one 37'1" strip cut from a 12' roll. Finally, the number of tackless strips 433 required to install the job is also drawn by the plotter.

Attention will now be directed to the flow charts comprising FIGS. 2a-2e which will be cross-referenced to the program listing in Appendix 1 along with a brief description of the operation being performed.

Turning to FIG. 2a, there are shown a group of steps bracketed at 201 which serve to initialize the system. The corresponding program steps are found in Appendix 1 at addresses beginning at 1 and ending at 101. It is seen that the screen of the CRT is cleared, areas of memory are set aside for storage of arrays of signals, and a group of variables is initialized. The input scale factor instruction 202 of FIG. 2a includes both the display of the prompt, which is accomplished by the step at address 102, as well as the actual input of the signal from the keyboard, which is accomplished at address 130. The succeeding steps at addresses 130 through 150 accomplish the step 203 of the flow chart, namely, calculation of a scale factor for use within the program corresponding to that entered by the operator.

Initialization of the window identified as step 204 in the flowchart (and address 160 in the program) serves to set limits for maximum display area of the CRT to be used. The Textronix graphics terminal automatically scales the data within the defined window area, to fully fill the graphic display. Similarly, the step 205 (accomplished at address 170) serves to set limits determin by the scale factor for travel of the pen on the plotter. The prompting message is cleared from the screen at step 206 (addresses 180 and 190).

The program sets aside a section of memory for storage of an array of signals relating to the coordinates of the dimensions of the given area which are to be input by the operator. Those arrays are initialized at 207 on the flowchart and by the corresponding code beginning at address 200 and encompassing the subroutine beginning at address 880. In effect, an area of memory is set aside which is three entries wide (X, Y and Z) and 200 entries long, and for purposes of convenience the number 201 is initially stored in each element of that array. The first coordinate entry is set to zero by the code beginning at address 230 and ending at address 250. This corresponds to the initial plotter pen position. The plotter starting point is set at step 209 of the flowchart, by the code located at address 260 through 300, which moves the pen to the position previously set into the array at the second coordinate array entry, corresponding to a point a fractional distance in relation to the height and width of the display area from the pen origin at the zero coordinates, in order to establish a margin on the drawing and on the display.

The program progresses to the step identified as 210 in the flowchart which encompasses the display of the prompting message for inputting the horizontal dimension (code address 330), and also the input of that number by the operator (address 340). The operator inputs the address in feet and inches as previously described. The subroutine beginning at address 370 serves to convert that number to decimal feet for further operation. The number so converted is then converted to a coordinate by the code at address 490 which adds that number to the X coordinate in the previous location of the array, such tat reading down the X array one will encounter a succession of X coordinates for each sequential corner of the plotted area. Following the sequence indicated in the listing, the program advances through the step at address 2900 and returns to the address 550 where a Y signal is entered in this level of the array which is the same as the Y signal in the previous location. In the exemplary embodiment, only the entry of horizontal or vertical lines is allowed, such that only the X or Y coordinate will change in any given step. Since the step under consideration had been the entry of the horizontal dimension, it is seen that the horizontal or X coordinate had been altered according to the entered dimension, whereas the Y coordinate remains the same as the previous entry.

The program progresses to the address 560 where the draw decision prompt is displayed on the CRT. The operator performs the step 211 by entering either 0 for No Draw, 1 for Draw or 2 for Terminate. Terminate is only used at the end of the sequence after all of the data has been entered. Accordingly, in the present circumstances either 0 or 1 is input by the operator, which value is entered in that level of the array as the corresponding Z value (address 570). The No Draw action is accomplished on the plotter by the step at address 620, whereas the draw is accomplished by the instructions at addresses 590 and 600.

In either case, the program progresses to the inputting the vertical dimension indicated at 216 in FIG. 2b. The associated code begins at address 330, and operates much like the input of the horizontal dimension just described. The major difference is that the Y value of the associated step in the array is updated whereas the X value is carried through from the previous level. The program again sequences through the display of the Draw decision prompt and input 217, the branching instruction at 218, and either the draw operation 219 or the move operation 220, depending on operator selection. As indicated by the arrow A on FIG. 2b, the program then returns to the step 210 for input of a further horizontal dimension. Those routines continue to cycle until the operator is satisfied that all of the horizontal and vertical dimensions have been input. The operator then responds to the Draw decision input 211 or 217 by entering a terminate command which causes the execution of the step 221 clearing the CRT screen.

At this point, the system has been provided by the operator with all of the raw data which defines the given area to be covered. The array of signals which stores such data is an array of coordinates defining the location of each direction change from horizontal to vertical or vertical to horizontal. The sequence of that information in the array corresponds to the sequence around the perimeter beginning from the starting point, such that not only is the information in any step of the array important, but also the sequence of information through the array.

Following completion of those operations, the system then switches to the mode of operation which causes the input of information related to the dimensional characteristics of the material. A first operation 225 prompts the operator to input the horizontal pattern (code address 1110) and accepts that information and converts it to decimal feet by the steps stored at addresses 1120 through 1150. As shown in FIG. 2b, if a 0 is entered in response to the "Input Horizontal Pattern" prompt, the test at 226 causes a branch to an operation 227 which sets a flag internally and causes the program to advance beyond the remaining input sequence dealing with the dimensional characteristics of the pattern.

Assuming that a dimension was entered for the horizontal pattern, the test 226 yields a negative result causing the program to advance to an operation 228 which prompts the operator to input the vertical pattern dimension. The steps for that prompt as well as the input and succeeding operations begin at address 1180 and follow in sequence. The operator is prompted at operation 229 to inform the system whether the pattern should be printed out on the plot to be made. If the operator provides an affirmative response, the test at 230 is positive, causing an operation at 231 to set a flag which will cause the pattern to be printed. The program sequences to an operation 232 which asks whether a drop pattern is involved, advancing the sequence to a test at 233. If the operator indicates that a drop pattern is involved, a drop flag is set at operation 234, following which the program advances to an operation 235. This is also the point to which the program branches, if the information provided by the operator at operation 225 indicated that no pattern was involved.

In responding to the prompt at step 235, the operator determines whether or not he wants the system to calculate the number of tackless strips required to install the job. If he does, information is input which causes the test at 236 to yield a positive result, setting a flag at operation 237 which will cause the perimeter of the given area to be measured. It is noted that the perimeter dimension is calculated at address 590 during input of the area dimensions. The program advances to an operation 238 which prompts the operator to input the roll width and which accepts that information when typed in.

In summary, the system has now been provided with all of the perimeter information of the given area to be carpeted, and all of the dimensional information relating to the material to fit the given area. In addition, the partial plot produced to this point shows the outline of the area to be covered in the scale selected by the operator.

In practicing the invention, the operator now uses the partially produced plot to input further information to the system for the purpose of generating a final plan. At the step 239, the system displays the prompt "Set Seam Position-Push Call" by means of executing the operation at address 22005. In response, the operator manipulates the joystick to position the plotter pen on the diagram at the location he has selected for a key seam. Upon depression of the call pushbutton, the operation at address 22010 serves to input the coordinates of the pen which had been positioned by the operator. The operations beginning at address 22010 and ending at address 22070, serves based on the dimensional characteristics of the goods, including the roll width and pattern dimensions if any, to determine the vertical location of each seam on the diagram. The first seam position, as detected by step 240, requires calculation of the initial seam and pattern positions via steps 242 and 243. Later seam and pattern positions are calculated from the initial positions, in step 241, using the strip width and pattern horizontal and vertical repeat increments. The horizontal locations of strip seams are manually entered via the call pushbutton in steps 244 and 245, corresponding to operation addresses 22090 and 22130. Since the horizontal and vertical seam and pattern coordinates are now defined, the seam and pattern can be drawn in steps 246 and 247, through operations at addresses 22140 to 32070 which generate horizontal dashed lines to indicate the seams and generate a periodic dot matrix to indicate the pattern.

The program then advances to the step 250 which prompts the operator to determine whether he desires to copy the program, rotate the diagram, go into the scrap routine, or modify the diagram which he had input to that point. The operator response is tested at 251 and the nature of the response indicates the manner in which the program will branch.

If, for example, the operator determines upon inspection of the partially produced plot that a seam is improperly located, he can type an M for "Modify" and revert to that portion of the program for selection of a new seam position. The program enters the modify loop at address 1720 and first performs an operation 252 which resets the scrap array. This is useful if the decision to modify the partial plot occurs after an attempt had been made to define source and destination for scrap. Following that, the operation 253 clears the screen, the operator is prompted to insert a new paper at 254 which, when accomplished, causes the system to display the outline of the area on the CRT by means of step 255 and redraws the diagram on the plotter at step 256. The screen is cleared by the instructions at addresses 1721 and 1722, the prompt is displayed by the instruction at address 1723. The branch for the subroutine which causes replotting of the outline is located at address 1735.

The corresponding point on the flowchart is shown by the designator C leaving the operation 256, and returning to the operation 239.

If on inspection of the partly produced diagram it is determined that it would be preferably to run the carpet length vertically on the diagram as opposed to horizontally, the operator responds to the prompt at step 250 by typing R to select the Rotate subroutine. The test 251 causes a branch to an operation 257 (beginning at address 2930) which, as indicated in the code, after performing some reinitiation, serves to interchange the X and Y coordinates at each level in the array. Thus, vertical coordinates become horizontal and horizontal coordinates become vertical which serves to rotate the diagram 90.degree. . The rotated diagram is then replotted using the operations 253-256 just as in the case of the Modify operation.

The partly produced diagram which exists when the step 250 is first arrived at is useful in identifying areas of carpet which might otherwise be scrapped, which can instead be used to cover small areas not reached by a full roll. More particularly, the room outline is displayed to scale, and the drawing of the seams (and pattern if desired) serves to show how the carpet material would overlie the room area. Any area of roll goods which is not coincident with the room outline is available for use elsewhere and can thus be identified as a scrap source for utilization at defined destination locations. Referring, for example, to FIG. 3, it is seen that the room outline there shown is "U" shaped. The width of the roll goods is insufficient to cover the entire leg of the U, but a large scrap source is located within the U. The manner in which the source area is identified and fit into the destination at the legs of the U will now be described. The program first branches from the test 251 to a step 260 (which begins with the subroutine at address 3400). A message is displayed to the operator instructing him to define the scrap destination and source by means of manipulating the plotter. The operator responds by manipulating the joystick to position the pen at point 400 in FIG. 3, following which he depresses the call button. The operation at address 3420 causes signals to be passed from the plotter to the processor, to store the coordinates of the point 400. The operator then repositions the pen to the point 402 and a similar operation is performed. Those steps serve to define a first destination area which will be covered with material taken from a specified source area now to be defined. Beginning at address 3540, the operator identifies to the processor the coordinates of the points 408, 406, the source area. The eight coordinates so entered are arranged in an array, termed the U array in a predetermined order.

Referring to the listing in the appendix, it is seen that the response to the prompt displayed at address 1660 is detected at address 1680 and causes the program to branch to address 6620. The program then immediately branches to address 3400 to perform the scrap input routine. The instruction at address 3400 causes an appropriae prompt to be displayed, following which two coordinates for the destination location and two coordinates for the source location are entered and stored in the U array. The program then returns to address 6640 which initially establishes a B array having coordinates equal to those in the U array, and a D array having four coordinates equal to the source coordinates in the U array. As will become more apparent, the coordinates in the D and B arrays are modified as the sequence progresses to indicate unused source or unfilled destination areas.

Upon reaching address 6700, the program branches to the subroutine at address 4470 which calculates a set of offsets relating the source and destination coordinates to reference points in the pattern. This is the area of the sequence which assures that the destination will be fit with an area taken from the source which matches the pattern at the destination. It is seen that the program branches to a subroutine beginning at address 4360 which calculates a vertical offset dimension at address 4380 and a horizontal offset dimension at address 4415. The sequence beginning at address 4510 takes account of a drop pattern if that is present.

The offset dimensions generated are used in the following manner. At address 4650 the calculated horizontal offset is added to the leftmost source coordinate to create a coordinate within the source defining the lefthand edge of the destination and which will match the pattern at the destination. The operation at address 4670 thereupon calculates the coordinate of the righthand edge of the source portion which will fit the destination. A similar operation for the vertical coordinates to be cut from the source is carried out beginning at address 4730.

The program then branches to address 6702 which matches coordinates to assure that there is adequate source to fit the desired destination. If there is not, the program defaults to address 1650 which it again displays the "C=copy, R=Rotates S=Scrap M=Modify" message allowing the operator to again attempt to identify a compatible source and destination. However, assuming the fit is proper, the program branches to the operation at address 10000 which serves to print corresponding numeric identifiers in the center of the source and destination which have been identified. The program then branches to a routine beginning at address 4849 which sets up an array of coordinates defining the corners of the identified destination and source portion. As can be seen from the code, the coordinates are stored in the XYZ array at previously unused locations just beyond those in which the original area coordinates had been stored. It is seen that twelve coordinates are set up in such a way that if they were drawn in sequence, a pair of rectangles with diagonal lines would be produced. The source diagonal runs from upper left to lower right and the destination diagonal from lower left to upper right in order to distinguish the two. After setting up the coordinates, at address 5290 the program is instructed to branch to the subroutine address 3190 which serves to draw the source and destination rectangles with opposed diagonals on the hard copy.

Following that, the program branches to address 4800 where the coordinates for the D array are updated to account for the partial use of the source. The numbers remaining in the D array represent the coordinates of the horizontal strip adjacent that taken from the source which remains after the source portion is taken.

The program is then caused to branch to address 7000 which allows the operator to input a second destination set of coordinates if there is sufficient scrap left within the source. It will be apparent from Appendix 1 that the operation is very similar to that just described. More particularly, the program branches to addess 9200 which prompts the operator to enter a new destination, then processes the entered information as generally described above.

Assuming that no new destination is required, the program thereupon branches to address 1650 which displays the familiar "C=Copy M=Modify R=Rotate S=Scrap" message. Even though the operator is this far into the program, he still has the option of selecting any of the four functions, including identification of a new source and destination for scrap.

When the operator is finally satisfied with the plot being produced, he selects the Copy option by depressing the C key on the keyboard, which causes the program to branch to address 2220, then to address 5600.

A message is displayed to the operator asking to pick off left-right dimensions of the respective lengths. The program advances to address 5650 which causes the zeroing of a set of arrays whose functions are as follows: The K element stores the left horizontal component for each strip, the L element stores the right horizontal coordinate for each strip, the P element stores the vertical coordinate (at which will be printed a strip identifying number), the R element stores the left offset into the pattern, the S element stores the right offset into the pattern, the G element is used to sequentially number the strips and the J element to store a waste factor created by the offsets. The branch to address 17,000 serves to enter sequential numbers in the G element of the array from 1 through 30.

The CRT is then used to display the prompt "Pick Off Left, Right (Call)". As described previously, the operator then manipulates the pen to define the left and right coordinate for each strip. The numbers are sequentially entered into the array by the subroutine extending from address 5690 through 5823. When all of the strips are defined, the program branches via address 5826 to the subroutine beginning at address 11,200 which serves to smooth the numbers so entered. Following return to address 5827, a routine is executed which determines the left and right offsets, and stores that information in the array. The instructions at addresses 5930-5945 serve to print the strip identification number to the right of the strip. The operation proceeds for each strip which had been identified by the operator.

When all strips have been identified and all offsets calculated, the address 5965 causes a branch to the subroutine beginning at address 13,000.

When an installation has a number of adjacent carpet lengths (as, for example, in FIG. 4) and it is necessary to match the pattern between lengths, there is often waste generated between the end of one strip and the beginning of the next in order to bring the patters into register. The sequence of steps beginning at address 13,000 is intended to determine the optimum manner of taking the strips from the roll in order to minimize this inter-strip waste. It is seen that the step at address 13,100 compares the righthand offset of a first strip to the lefthand step of the next adjacent strip in order to determine how much waste would be created if those strips were cut from the roll in sequence. The base strip is compared to each of the other strips in that manner, with the partial results being stored at Q5 and Q7. When the minimum waste combination is determined, the program advances to address 15,000 which serves to rotate the order of the strips in the array memory, leaving them in an order which minimizes inter-strip waste.

After the sequence has been performed which determines the order of cutting of the strips to minimize inter-strip waste, the program reverts to address 5970, which directs the sequence to address 6240 for printout of supplemental information. As can be seen from the code beginning at address 6240, supplemental information can include blanks for entry of the store number, sales person name, and customer identification, as well as the printout of numerical data such as material length, material width and pattern repeat dimensions, total number of square yards and the number of tackless strips required. The program ultimately advances to the address 6510, which reverts to the start, leaving the machine in condition for producing the next plot.

It will be seen that what has been provided is a method and apparatus for estimating carpet or floor covering material installations which not only serves to minimize material waste, but also accomplishes that in a fullproof manner, virtually eliminating the possibility of sending insufficient carpet to an installation. There is no need to add a percentage of carpet to the estimate "for insurance". If the installation works on the plotter, the installer can be assured that if he cuts and installs the carpet according to the plan, the job will go in as designed. The ability of the operator to interact with the plot as it is being produced allows great flexibility in tailoring the layout as well as lending him assurance that while he is tailoring the layout he is not introducing errors. ##SPC1## ##SPC2## ##SPC3##