JPH05210748A - Shading plotting system - Google Patents

Abstract

PURPOSE:To speed up shading plotting in a bit-mapped display memory. CONSTITUTION:A CPU 1 generates data and a plotting instruction for executing shading. A DDA 2 finds out the delta value of a color necessary for shading from color information applied from the CPU 1. A memory control part 3 controls a display memory 4. The memory 4 has a shading writing function. A delta value storing part 5 stores the delta value of the color information found out by the DDA 2. An integration part 6 multiplies the delta value stored in the storing part 5 by an integer. An addition part 7 adds the value obtained by multiplying each delta value by an integer which is outputted from the integration part 6 to the starting point color information obtained from the CPU 1. A memory cell 8 stores data corresponding to a color to be plotted. A D/A converter 9 converts a digital signal outputted from the memory 4 into a displaying analog signal and displays the converted contents on a CRT 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a graphic processing apparatus having a bit-mapped display memory, and more particularly to a method of drawing a shading graphic.

[0002]

2. Description of the Related Art Conventionally, in this type of drawing method, shading of color information and the like are all calculated by one pixel in one cycle by an adder outside the display memory, and each pixel is written in one display memory. Are doing.

[0003]

In the conventional drawing method,
At the time of shading drawing, only the number of pixels corresponding to the data bus width of the display memory can be drawn at a time, and the data bus width of the memory is restricted by the device configuration and cannot be made too large. However, there is a drawback that it cannot be drawn. In addition, there is a block write function in the memory that draws several pixels at the same time for high-speed drawing, but it can not be used to draw a shaded figure with different brightness values for each pixel because it can write multiple pixels at the same time. There are drawbacks.

[0004]

The shading drawing method of the present invention is applied to a bit map display memory.
Means for storing a delta value indicating the amount of change in color information between pixels for drawing a shading figure, multiplication means for multiplying the delta values of two or more equations by an integer, and integers of two or more equations corresponding to the multiplication means An addition means for adding the multiplied delta value to the given color information, and the addition of the integer-multiplied delta value to the color information by the addition means at the same time causes the luminance of a plurality of pixels in the display memory. A feature is that a shading figure is drawn by simultaneously calculating and writing a value.

[0005]

The present invention will be described below with reference to the drawings. 1 is a block diagram of the first embodiment of the present invention. C
The PU (control circuit) 1 generates data for shading, drawing commands, and the like. DDA (digital
l differential analyzer) 2
Calculates the delta value of the color required for shading from the color information (start point color information and end point color information of the straight line) given from the CPU 1. The memory control unit 3 controls the display memory 4. The display memory 4 has the function of a shading light (delta value storage unit 5, integrating unit 6, adding unit 7) in addition to the function of the conventional display memory. Delta value storage unit 5
Stores the delta value of the color information obtained by DDA2. The integration unit 6 multiplies the delta value stored in the delta value storage unit 5 by an integer. The addition unit 7 adds a value that is an integral multiple of each delta value from the integration unit 6 to the starting point color information from the CPU 1. The memory cell 8 stores data corresponding to the drawn color. The D / A converter 9 converts the digital signal from the display memory 4 into an analog signal for display. The CRT 10 is a display for display. FIG. 2 shows a drawing image of an embodiment of the present invention.

In the configuration of FIG. 1 described above, the CPU
When the address, the starting point color information and the ending point color information are given from 1, the DDA 2 obtains a delta value [(ending point color information-starting point color information) / (ending point X coordinate-starting point X coordinate)] and sets it in the delta value storage unit 5. To do. The value set in the delta value storage unit 5 is multiplied by 1 times, 2 times, 3 times, ... J times by the integration unit 6, and then, by the shading drawing command of the CPU 1, the addition unit 7 causes the starting point color information from the DDA 2 to be added. 2 is added at once to each memory cell 8 and written to the memory cell 8. As a result, as shown in FIG. 2, from the designated coordinates to the j-th pixel are shaded and drawn at one time.

FIG. 3 is a block diagram showing a second embodiment of the present invention, showing an embodiment in which shading writing is performed by the block writing function of the memory. In the configuration of FIG.
A multiplication value calculation unit 11 for obtaining a multiplication factor for the delta value from the number of write signals from the memory control unit 3 is added, and while the RAS (row address strobe) signal from the memory control unit 3 is falling, the CAS (column address strobe) )
When the counter of the multiple value calculation unit 11 counts the number of falling edges of the data (initial value C = 0) and the number of pixels that can be written at one time is j, each multiple (1, 2, 3, ...
By adding C × j to j) at the fall of CAS, shading block writing can be performed at high speed every fall of CAS. The effect is the same even if WE (write enable) is used for write control or the count is set to the rising edge of the write control signal.

FIG. 4 is a block diagram showing a third embodiment of the present invention, showing an embodiment when an n.times.m memory boundary structure is adopted.

A multi-value calculation storage unit 14 is added to the configuration of FIG. 1 to determine the number of pixels in the horizontal configuration from the CPU 1 when the apparatus starts up (n), and the number of memory from the left of each memory (i). By giving a value, a multiple value for each pixel can be calculated and stored, and a shading light of n × j (one memory is each pixel at a time) pixels can be performed at a time.

FIG. 5 is a block diagram of the fourth embodiment of the present invention, showing an embodiment in which a plurality of memories are provided in the depth.
A carry input / output unit 16 is added to the configuration of FIG.
The carry data generated by adding the start point color data and the delta value by the adder 7 is sent to the memory in the depth direction. If there is a carry, the data is added to the integrating unit 12 and the adding unit. By adding in 7,
Even when the depth has a plurality of memories, it is possible to perform shading lights of n × j (one memory has each pixel number at a time) pixels at a time.

[0011]

As described above, according to the present invention, in the bit-mapped display memory, means for storing the delta value indicating the amount of change between pixels of the color information for drawing the shading figure, and two or more equations. Using a memory element having multiplication means for multiplying the delta value by an integer and addition means for adding an integer-multiplied delta value of two or more equations corresponding to the multiplication means to given color information. By simultaneously adding the delta value multiplied by an integer by the means to the color information to simultaneously calculate and write the brightness values of a plurality of pixels in the memory element, it is possible to draw a shaded figure at high speed. .. * Having a means for counting the number of times of writing and a means for calculating a multiple of the delta value according to the value of the counting means, and automatically generating a multiple of the delta value in the memory element according to the write, By simultaneously calculating and writing the brightness values of a plurality of pixels in the inside, it is possible to draw a shading figure at high speed. * Has a means to arbitrarily set a value that is an integral multiple of the delta value depending on the memory configuration, and simultaneously calculates and writes the brightness values of multiple pixels in an arbitrary memory configuration (n × m) to draw a shading figure at high speed. There is an effect that can be done. * A means for passing carry information generated when an integer multiple of a delta value or when an integer multiple delta value is added to color information is provided between each memory element, and a plurality of memory elements are combined. This has an effect that a brightness value larger than the data bit width of one memory element can be calculated.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a first embodiment of the present invention.

FIG. 2 is a diagram showing a drawing image according to an embodiment of the present invention.

FIG. 3 is a configuration diagram of a second embodiment of the present invention.

FIG. 4 is a configuration diagram of a third embodiment of the present invention.

FIG. 5 is a configuration diagram of a fourth embodiment of the present invention.

[Explanation of symbols]

 1 CPU 2 DDA 3 Memory control unit 4, 13, 15 Display memory 5 Delta value storage unit 6 Integration unit 7 Addition unit 8 Memory cell 9 D / A converter 10 CRT 11 Multiple value calculation unit 12 Integration unit 14 Multiple value calculation storage unit 16-carry input / output section

Claims (4)

[Claims] 1. A means for storing a delta value indicating a change amount between pixels of color information for drawing a shading figure in a bit-mapped display memory, and a multiplication means for multiplying the delta values of two or more integers by an integer. And adding means for adding the delta value multiplied by an integer of two or more corresponding to the multiplying means to the given color information, and the delta value multiplied by the integer by the adding means is added to the color information at the same time. A shading drawing method characterized in that a shading figure is drawn by simultaneously calculating and writing the brightness values of a plurality of pixels in the display memory by adding them. 2. A means for counting the number of times of writing, and a means for calculating a multiple of the delta value according to the value of the counting means, and automatically generating a multiple of the delta value in the display memory according to the write. The shading drawing method according to claim 1, wherein 3. Means for arbitrarily setting a value that is an integer multiple of a delta value according to a memory configuration, and an arbitrary memory configuration (n
2. The shading drawing method according to claim 1, wherein the brightness values of a plurality of pixels are simultaneously calculated and written in xm). 4. A means for passing carry information, which is generated when a delta value is multiplied by an integer or when an integer multiplied delta value is added to color information, between the respective display memories, and a plurality of displays are provided. 4. The shading drawing method according to claim 3, wherein a brightness value larger than a data bit width of one display memory can be calculated by combining the memories.