JP2000347651A - Picture drawing processing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a load on a CPU concerning coordinate transformation process and make high speed coordinate transformation possible by constituting the device by providing a coordinate transformation part in a picture drawing processing part. SOLUTION: In a picture drawing processing part 0101, a picture drawing control part 0103 performs monitoring of pipe line control of a series of picture drawing process, decoding of the command of a straight line or a rectangle picture drawing, pretreatment for picture drawing slant of a straight line or the like. An image data holding part 0108 stores image data for picture drawing sent from the outside, a coordinate transformation part 0102 transforms coordinate such as rotation or conversion to a bird's-eye view. A picture drawing part 0104 performs actual drawing such as drawing of a straight line or paint- out process of a rectangle for outputting to an outer display device 0111, an image plane information holding part 0107 stores data for generated display, and a display control part 0105 performs a process displaying the display data to a display device 0111. The coordinate transformation process executed by a CPU 0109 is transferred into pipe line operation of the picture drawing process.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a configuration of a drawing processing device in a car navigation system and other image information processing systems, and high-speed coordinate conversion.

[0002]

2. Description of the Related Art FIG. 6 shows an example of a conventional drawing processing system. FIG. 7 shows a drawing processing device in the conventional drawing processing system. As shown in FIG. 7, the configuration of the conventional drawing processing apparatus is such that an image data holding unit for storing drawing data sent from the outside and decoding commands such as straight line drawing and rectangular drawing are provided. A drawing control unit that performs pre-processing of drawing such as the inclination of a straight line, a drawing unit that performs actual drawing in response to a drawing command decoded by the drawing control unit, and a screen that holds data drawn by the drawing unit The information storage unit includes a display control unit that controls display of data drawn on the screen information storage unit on a display device such as an external CRT. Next, in the drawing processing system shown in FIG. 6 including such a drawing processing device 0701 as shown in FIG. 7, a drawing process when coordinate conversion is included will be described. First, in response to a command from the CPU 0601, the CPU 0601 transfers the image data of the corresponding address portion in the image data holding unit necessary for drawing the screen of the image data holding unit 0606 to the CPU memory 0607.
Next, the CPU 0601 calculates parameters required for the coordinate conversion. Using the obtained parameters, the image data previously transferred to the CPU memory 0607 is
U0601 performs a coordinate conversion operation. The CPU 0601 transfers the coordinate-converted image data to the drawing processing unit 0602, and stores the image data in the image data holding unit 0705. Based on the stored data, the drawing control unit 0703 performs pre-drawing processing such as calculation of the inclination of a straight line, transfer of a drawing command, decoding, and the like, and sequentially transfers information necessary for drawing to the drawing unit 0702. With respect to the transferred drawing information, the drawing unit 0702 performs drawing on the screen display data, and the screen information holding units 0608 and 070
Transfer to 6. Finally, the screen information holding units 0608 and 070
The display control unit 0704 displays the screen information transferred to the CRT 6 on the CRT.
Is displayed on the external display device 0604, and a series of operations is completed.

[0003]

However, in such a conventional configuration, the CPU, which increases the load due to a multifunctional and sophisticated system, performs coordinate conversion such as image rotation and perspective projection. By further adding a process, for example, when considering a high-speed scrolling in a three-dimensional, bird's-eye view display state of the screen, the CPU performs coordinate conversion to perform smooth scrolling in order to realize smooth scrolling.
Processing for coordinate conversion, such as generation of parameters for coordinate conversion, coordinate conversion calculation, transfer of drawing data, and drawing is continuously performed, and the CPU is occupied by the task for coordinate conversion and drawing processing. Frequent transfer of image data also causes traffic congestion on the main bus, which lowers the performance of the entire system.

In addition, when the screen is scrolling as compared to when the screen is in a stationary state, coordinate conversion must be performed one after another. In particular, when performing coordinate conversion including division that requires the number of cycles, the screen must be converted. There is a problem that hinders smooth scrolling. In addition, the CPU must create new coordinate conversion parameters one after another, for example, when the screen is rotating, and the coordinate conversion parameters are always used. It is necessary to perform parameter generation and coordinate conversion calculation, which also causes a considerable load on the CPU, occupies the main bus at the same time, and causes a problem that the performance of the entire system is deteriorated.

SUMMARY OF THE INVENTION Accordingly, the present invention has been made in view of the above problems, and has as its object to provide a drawing processing apparatus for realizing high-speed coordinate conversion in a drawing processing system, and to provide a drawing processing apparatus for reducing the load on a CPU in the system. Is to do.

[0006]

SUMMARY OF THE INVENTION According to the present invention, in a drawing processing system, the function of performing coordinate conversion processing conventionally performed by a CPU is transferred to a drawing processing apparatus to reduce the load on the CPU and realize high-speed coordinate conversion. is there.

More specifically, according to the present invention, a coordinate conversion unit, a pre-drawing process for calculating a slope of a straight line, and a screen operation control unit are set in a drawing processing apparatus directly or via a CPU. For the mode of whether or not coordinate conversion is necessary, a series of processing flow of coordinate conversion processing, pre-drawing processing, drawing processing, and display processing is set when it is set as necessary. A new drawing control unit for performing pipeline control of a series of processing flows excluding conversion is provided.
This is a drawing processing apparatus having a configuration capable of shifting the coordinate conversion processing performed in the above to the pipeline operation of the drawing processing.

According to the present invention, the division accuracy required for coordinate transformation (particularly, perspective projection transformation, etc.) can be set with respect to the operation state of the screen sent from the outside of the drawing processing device. A setting register, comprising a division control unit capable of switching the accuracy of division according to the accuracy set in the division accuracy setting register, wherein high-speed coordinate conversion is possible even when the screen is moving such as scrolling. This is a drawing processing device.

According to a third aspect of the present invention, there is provided a coordinate conversion unit further including a trigonometric function value generating device, wherein a coordinate conversion parameter (affine) using a trigonometric function value required for coordinate conversion such as rotation. Parameters) are not created outside a drawing processing device such as a CPU, but information such as a screen rotation angle and a parallel movement distance are set from the outside, and a parameter generation control unit in the coordinate conversion unit is set based on the information. Is a drawing processing device that can be self-generated by the coordinate conversion unit.

[0010]

(Embodiment) FIG. 1 is a configuration diagram of a drawing processing system including a drawing processing apparatus of the present invention.
The drawing processing unit in FIG. 1 shows the configuration of the drawing processing apparatus according to the present invention. FIG. 2 is a diagram more specifically showing the configuration inside the coordinate conversion unit. First, the configuration of the embodiment of the present invention will be described with reference to FIGS.

In FIG. 1, reference numeral 0101 denotes a drawing processing apparatus according to the present invention. The inside of the drawing processing apparatus is used for monitoring pipeline control of a series of drawing processing, decoding drawing commands such as drawing a straight line or a rectangle, and drawing a gradient of a straight line. Control unit 0103 for performing pre-processing and the like of image processing, an image data holding unit 0108 for storing image data for drawing sent from the outside, and conversion of image data sent from the outside to rotation and bird's-eye view Coordinate conversion unit 0102 that performs coordinate conversion processing such as
And a drawing unit 01 that performs actual drawing such as straight line drawing and rectangle filling processing for output to an external display device.
04, a screen information storage unit 0107 for storing display data generated by the drawing unit, and a display device 0 such as an external CRT for storing the display data stored in the screen information storage unit.
And a display control unit 0105 that performs display processing on the display unit 111.

An embodiment of the present invention according to claims 2 and 3 will be described with reference to FIG. In the coordinate conversion unit, a multiplier 0208 and an adder 020 for performing coordinate conversion
9 and an arithmetic control unit 02 that controls addition (including subtraction) and multiplication-based operations (including multiplication, addition, and subtraction).
05, a trigonometric function value generator 0210 for generating a trigonometric function value necessary for coordinate transformation from information on a change in angle such as a rotation angle of a screen input from the outside of the drawing processing apparatus; Input from outside the drawing processing device,
A parameter generation control unit 0207 for generating coordinate conversion parameters from the screen displacement information, image data to be subjected to coordinate conversion, displacement and angle information necessary for generating the coordinate conversion parameters, and information on these displacements. , A data temporary holding unit 0212 for storing coordinate transformation parameters and the like created by the parameter generation unit, and a reciprocal generation device 021 for generating an approximate value of a reciprocal of a denominator required for performing division.
1 and a division accuracy setting register 0216 that can set the operation state of a plurality of screens such as a static state or a high-speed scroll state set from outside the drawing processing apparatus.
And a division control unit 0206 capable of switching the accuracy of division during coordinate conversion operation according to the operation mode of the screen set in the division accuracy setting register.

FIG. 3 is a flowchart of a drawing process according to the first embodiment.

The drawing process according to the present invention will be described below with reference to FIGS. 1, 2 and 3.

In S0301 of FIG. 3, CPU010
9 designates a drawing target address in the image data holding unit 0112. Here, the real designation address may be a unit indicating a region to be drawn, such as coordinates, or information such as the division number when divided.

In S0302, the image data of the area designated in S0301 is transferred to the image data holding unit 0108 in the drawing processing unit 0101.

In step S0303, the screen operation control unit 01
Whether or not the coordinate conversion is necessary is set in an internal register in the drawing control unit 0103 directly or via the CPU 0109 according to the input from 10. If it is determined in step S0303 that coordinate conversion is required, in step S0304, the screen operation control unit transmits values such as displacement and rotation angle required for generating coordinate conversion parameters to the CPU 0109.
The data is transferred to the data holding unit 0115. Next, in S0305, based on the value transferred to the CPU data holding unit 0115 in S0304, parameters necessary for coordinate conversion are determined by the CPU.
It is generated in 0109 and transferred to the temporary data storage unit 0212 in the coordinate conversion unit 0102. The coordinate transformation parameters are, for example, affine transformation parameters which are two-dimensional and three-dimensional coordinate transformation parameters shown in Chapters 4 and 5 of "Introductory Graphics" by Yoshio Sato, ASCII Publishing Co., Ltd. .

In S0306, the CPU 0109 executes S
Using the parameters generated in 0305, the image data (coordinate point data) of the area specified in S0301 is
The coordinate conversion unit 0102 performs a coordinate conversion operation.

If it is set in step S0303 that coordinate conversion is not required, or in step S0305, the image data to be drawn is stored in the image data holding unit 0108 in the drawing processing unit 0101 in step S0306. Is transferred after executing the desired coordinate transformation.

In step S0307, the drawing control unit 0103 performs a pre-drawing process, such as a calculation of the inclination of a straight line necessary for the drawing process and, if necessary, a clipping process of cutting out a portion protruding from the drawing area.

If it is determined in step S0308 that coordinate conversion is not required in step S0303, the image data transferred to the image data holding unit 0108 is directly used in step S03.
If it is determined in step 03 that coordinate conversion is necessary, the drawing process is performed on the image data that has been coordinate-converted in steps S0304 and S0305 and transferred to the image data holding unit 0108 again. Specifically, for example, "Introductory Graphics" by Yoshio Sato, described above, straight line drawing by the DDA method described in Chapter 3 of ASCII Publishing Co., Ltd. Draw contour lines based on the straight line drawing and fill the inside Processing such as polygon drawing. Then, the drawn data is transferred to the screen information holding unit.

In step S0309, the data drawn in step S0308 is displayed on the CRT using the display control unit 0105.
And the like on the display device 0111.

As described above, by newly providing the coordinate conversion processing in the drawing processing unit, it is possible to reduce the load on the CPU in the drawing processing, and to realize multifunction and high functionality of the entire system. In addition, it becomes possible to eliminate the traffic of the main bus which becomes extremely congested during the coordinate conversion.

FIG. 4 in addition to FIGS. 1, 2 and 3 is a diagram showing an operation flow when division is executed in S0305 and S0306 of FIG.

Here, the coordinate conversion processing will be described in accordance with the present invention as set forth in claim 1 in which a coordinate conversion section is provided in a drawing processing section.
In the case where the coordinate conversion process is performed by using, the same operation can be performed.

In step S0401, the coordinate transformation unit 010
When it is determined that the signal No. 2 is not executing (due to the setting of the flag register, etc.), in step S0402, the operation mode of a plurality of screens such as a stationary state and a high-speed scroll state is changed to the screen operation mode. It is set in the screen operation mode register of a certain assigned area in the external setting register 0204 in the coordinate conversion unit 0102 directly from the control unit 0110 or via the CPU 0109.

Here, it is assumed that modes such as stationary, scrolling, and high-speed scrolling can be set as three types of modes.

If it is determined in step S0401 that the coordinate conversion has been performed, the setting is performed again after the coordinate conversion end flag from the coordinate conversion unit is turned ON.

In step S0403, when division occurs during the coordinate conversion processing, the process enters division processing S0404. Here, the division operation is a division by a convergence operation such as the Newton-Raphson method using the multiplier 0208 in the coordinate conversion unit 0102, the reciprocal value generation unit 0211 of the denominator, and the division control unit 0206. It is assumed that the division with the highest precision is performed in Expression 5.

If the screen operation modes 1, 2, and 3 are defined as high-speed scroll, scroll, and still mode, respectively, in the high-speed scroll mode (screen operation mode 1), even if the coordinate conversion is performed with the accuracy of division lowered, the highest is obtained. It is difficult to recognize the difference from the one calculated with accuracy. Therefore, in order to execute a division with a small number of processes, that is, a small number of processing steps, that is, a division with the lowest accuracy, in the division S0404, refer to the screen operation mode set in a certain assigned register in the external setting register 0204 in S0402. Then, the necessary processing in all the processing steps of the division with the highest accuracy is selected and executed. Here, the processing 1 and the processing 5 are selected and the division is performed.

If the scroll mode (screen operation mode 2) is set in step S0402, the scroll operation is performed, but the screen moves at a lower speed than the screen operation mode 1 and the calculation is performed with the highest accuracy. The difference is easier to recognize than in screen operation mode 1. Therefore, referring to the screen operation mode register in the external register 0204, the processes 1, 2, 3, and 5 are selected here in the same manner as in the screen operation mode 1 in the division process S0404. A highly accurate division is performed, and the speed is reduced to some extent to perform a coordinate transformation with an accuracy that is not visually strange.

In the case where the screen operation mode 3 is set in S0402, since the screen is in a stationary state, even a slight shift of the drawn image can be recognized. Therefore, in this case, the division with the highest precision is executed to perform the coordinate conversion. As described above, the time-consuming division is used for each of the multiple screen operation modes in the coordinate transformation operation, and the division is used for each accuracy. In this case, it is possible to satisfy the performance such as performing the calculation at a high speed and performing the calculation with higher accuracy when the vehicle is stationary. Here, a multiplier is used for division, but it is also possible to use a dedicated divider in a similar manner.

The flow of the third embodiment of the present invention will be described with reference to FIG. 5 in addition to FIGS.

Unlike the first embodiment, the coordinate conversion unit 0102 includes a parameter generation control unit 0207 and a trigonometric function value generation unit 0 in the coordinate conversion unit as shown in FIG.
This is a drawing processing device provided with the image processing device 210.

In step S0501, a drawing target area in the image data holding unit 0112 is specified in the same manner as in the first embodiment.

In S0502, the image data of the area designated in S0501 is transferred to the image data holding unit 0108.

In step S0503, if the value indicating whether or not to perform the coordinate conversion set in the area designated by the screen operation control unit in the external register 0204 is set to a state in which no coordinate conversion is performed, the process proceeds to step S0506. S05
In step 01, the image data of the designated area in the image data holding unit 0112 is transferred to the image data holding unit 0108.

On the other hand, if it is determined in step S0503 that the coordinate conversion is required, then in step S0504 the rotation angle with respect to the reference coordinate axis of the screen input from the screen operation control unit 0110 and the parallel movement of the screen are determined. The resulting shifted value is transferred directly or via the CPU to the data temporary holding unit 0212 in the coordinate transformation unit 0102 (for these parameters, "Introductory Graphics" by Yoshio Sato ASCII Publishing Co., Ltd. (See Chapters 4 and 5).

In step S0505, a coordinate transformation parameter (affine parameter) is generated using the trigonometric function value generation unit and the parameter generation control unit based on the angle and the displacement value set in step S0504, and the data is temporarily stored in the data storage unit 0212.
To memorize.

If it is determined in step S0503 that coordinate conversion is necessary, step S0506 is executed in parallel with step S0505 to transfer image data.

In step S0507, the coordinate conversion unit 0102 performs a coordinate conversion process on the image data transferred in step S0506 using the parameters generated in step S0505.

Thereafter, in the same manner as the flow of the first embodiment, in S0508, the drawing control unit 0103 performs pre-drawing processing such as calculation of the inclination of a straight line, and in S0509, the drawing unit 0104 performs DDA processing based on the DDA processing. In step S0510, the display control unit 0105 executes the CR process.
Display on a display device such as T is performed.

As described above, by adding the function of generating the coordinate conversion parameters in the coordinate conversion unit transferred to the drawing processing unit, the coordinate conversion parameters can be continuously converted especially during high-speed scrolling involving coordinate conversion such as rotation. Generation is required, but even in such a case, without occupying the CPU,
At the same time, the necessity of successively transferring coordinate conversion parameters through the main bus is reduced, so that congestion of the main bus can be eliminated.

FIG. 8 shows a more specific embodiment in which the drawing processing apparatus of the present invention is incorporated in a car navigation system. 1, a DVD-ROM 0812 in which map data, area information data, and other data such as telephone numbers and landscape photos are stored as an image data holding unit, and a remote controller as a screen operation control unit shown in FIG. The controller 0810, the vehicle speed detection sensor 0817, and an information receiving unit 0818 as a device unique to the car navigation system for performing the recognition of the position of the vehicle, the acquisition of traffic information, and other communication such as the Internet.
A voice recognition unit 0816 for a driver to control the system by voice, a liquid crystal monitor 0811 as a display device, a drawing processing device including at least the components of the drawing processing device according to the present invention, and a car navigation system. CPU 0809 for controlling the whole and peripheral circuits 0
813 and a data navigation system 0815 for the CPU.

The basic flow of the drawing process is stored in the DVD-ROM corresponding to the area around the position moved from the current position by the current position information from the own vehicle position information detecting unit or the remote controller input from that position. The CPU transfers the map data to the image data holding unit 0808 in the drawing processing device. Next, the user moves the map screen using high-speed scrolling controlled by the remote controller 0810, switches to a bird's-eye view display that displays a map in three dimensions, and scrolls the screen relatively slowly during driving (this is Own vehicle position information receiving unit 0
818 to generate displacement information using data such as how the user is moving on the map).
The coordinate conversion unit creates necessary coordinate conversion parameters. Here, the input related to coordinate transformation from the remote controller is, for example, when the display position is moved up and down and left and right to check what is around it, etc., when scrolling the map freely using the cross button etc. And so on. Coordinate conversion is similarly performed by the coordinate conversion unit using the created coordinate conversion parameters, and stored again in the image data holding unit. Next, the drawing control unit 0803 performs a pre-drawing process such as calculating the inclination of the straight line (there may be a case where a short straight line is not determined) and decoding a drawing command.
In 804, data for display is created, and the screen information holding unit 08 is created.
07. Finally, the map data stored in the screen information holding unit is displayed on the liquid crystal monitor 0811. In this embodiment, the coordinate conversion processing is based on the flow of the above embodiment. That is, the necessary division accuracy is set in the division accuracy setting register in the coordinate conversion unit shown in FIG. 2 from the movement signal on the map screen from the remote controller and the movement information during driving, and is also set by the division control unit shown in FIG. The division during coordinate conversion is performed by switching the operation flow of division according to the information, and the parameters of coordinate conversion such as rotation of the map are the rotation angles obtained by the movement information sent from the vehicle position information receiving unit. It is obtained from the information by using the trigonometric function generator and the parameter generation controller shown in FIG. Therefore, by moving the processing conventionally performed by the CPU to the inside of the drawing processing apparatus, and by further switching the accuracy of division, in high-speed coordinate conversion, CPU overload is prevented,
In addition, a smooth scroll can be realized.

[0046]

As described above, according to the first aspect of the present invention, the load on the CPU related to the coordinate conversion processing can be reduced by newly providing the drawing processing section with the coordinate conversion section. Is obtained.

Further, according to the second aspect of the present invention, the division accuracy can be switched for a plurality of assumed operation modes of the screen, thereby achieving the division satisfying the performance suitable for the screen operation mode. Is obtained.

According to the third aspect of the present invention, by adding the trigonometric function value generation section and the parameter generation control section to the coordinate conversion section moved to the rendering processing section, the coordinate processing which is the pre-processing of the coordinate conversion processing is performed. The effect of reducing the generation of the conversion parameters from the load on the CPU, and in particular, reducing the inconvenience such as the occupation of the CPU and the congestion of the main bus that occurs when the generation of the coordinate conversion parameters must be performed continuously, such as high-speed scrolling involving coordinate conversion. Is obtained.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a drawing processing system according to a first embodiment of the present invention;

FIG. 2 is a configuration diagram of a coordinate conversion unit including both Embodiments 2 and 3 of the present invention.

FIG. 3 is a flowchart of a drawing process according to the first embodiment of the present invention;

FIG. 4 is a flowchart for selecting and executing division processing according to Embodiment 2 of the present invention;

FIG. 5 is a drawing processing flowchart according to Embodiment 3 of the present invention;

FIG. 6 is a configuration diagram of a conventional drawing processing system.

FIG. 7 is a configuration diagram of a conventional drawing processing apparatus.

FIG. 8 is a configuration diagram of a car navigation system using the drawing processing device according to the present invention.

[Explanation of symbols]

0101, 0602, 0801 Drawing processing unit 0102, 0201, 0802 Coordinate transformation unit 0103, 0803 Drawing control unit 0104, 0804 Drawing unit 0105, 0805 Display control unit 0106, 0806 Drawing processing unit local bus 0107, 0807 Display screen information holding unit 0108, 0808 Image data holding unit for drawing processing (0
For the VRAM 608, 0107 and 0108 are shown together for simplicity.) 0109, 0601 and 0809 Central Processing Unit (C
PU) 0110 Screen operation control unit 0111, 0604 Image display device 0112, 0606 Image data holding unit (database) 0113, 0603, 0813 CPU peripheral unit 0114, 0605, 0814 System main bus 0115, 0607, 0815 CPU data holding unit 0202 Coordinate conversion unit data path unit 0203 Coordinate conversion unit control unit 0204 Coordinate conversion unit external register for each operation mode setting 0205 Coordinate conversion operation control unit 0206 Division control unit 0207 Coordinate conversion parameter generation control unit 0208 Multiplier 0209 Adder 0210 Trigonometric function Value generation unit 0211 Reciprocal approximation value generation unit for the number of denominators 0212 Coordinate conversion unit data temporary storage unit 0213 Arithmetic unit input selection unit 0214 Arithmetic unit output selection unit 0215 Input for coordinate conversion unit data temporary storage unit Selection unit 0216 Division accuracy setting register 0810 Remote controller 0811 LCD monitor 0812 DVD-ROM 0816 Voice recognition unit 0817 Vehicle speed detection sensor 0818 Own vehicle position information, WEB information reception unit 0819 Operation signal reception unit

Claims (3)

[Claims] 1. A drawing unit that performs a drawing process of a straight line, a rectangular figure, or the like, and coordinate point information necessary to perform drawing on the drawing unit, and pre-processing of drawing such as transfer of inclination information of a straight line.
A drawing control unit that controls the operation of the drawing processing apparatus in a pipeline manner, a display control unit that performs display processing of data drawn by the drawing unit on an external display device such as a CRT, and the like. And an image data holding unit for temporarily storing display data drawn by the drawing unit, and additionally performs rotation, bird's-eye view display, three-dimensional display, and the like. And a coordinate conversion unit for performing a coordinate conversion process necessary for the image processing. 2. In the drawing processing device, a screen operation mode (for example, a mode indicating a screen state such as a stationary state or a scroll state) sent from outside the present drawing processing device to the coordinate conversion unit. A division accuracy setting register for receiving and holding a signal, and an accuracy mode externally set in the division accuracy setting register are executed during a perspective projection transformation, which is a typical three-dimensional coordinate transformation, and the execution is multiplied. And a division control unit capable of switching control of division having a longer execution cycle than other operations such as addition. 3. A drawing processing device, wherein: a trigonometric function value generating unit for generating a trigonometric function value from information representing an angle in the coordinate conversion unit;
Receiving information such as parallel movement, and receiving information such as the rotation angle at the time of rotation of the screen, the moving width of parallel movement, and the scaling factor sent to the drawing control unit, and creating a transformation matrix parameter for coordinate transformation. And a parameter generation control unit for performing the control of (1), and capable of generating coordinate transformation parameters by itself within the drawing apparatus.