JPS6213673B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an image display control device, and in particular, when displaying an object in front as viewed from the viewer, the object in the foreground is made translucent so that objects behind the object in the overlapping area can also be seen slightly. The present invention relates to an image display control device for displaying images.

For example, in an image display device such as a graphic terminal used as a terminal device of a data processing device, when image data to be displayed is stored in the image memory 1, the image data to be displayed is displayed in red. The signal is stored as three digital signals of (R), green (G), and blue (B) in 1-bit screen memory areas 2, 3, and 4, respectively. Here, screen memory area 2 is for red lights, screen memory area 3 is for green lights, and screen memory area 4 is for green lights. When displaying these on the display monitor 8, the values of each component for the same pixel are read out simultaneously, and each is converted into an analog signal by digital-to-analog converters (hereinafter referred to as D/A converters) 5, 6, and 7. The image is then displayed on a display monitor 8 such as a color CRT.

Currently, red, green, and blue screen memory areas 2 to 4
, the shaded areas 2-0 and 3- are shown in Figure 2 A to C, respectively.
When images such as those shown as 0 and 4-0 are stored (the shaded portions are "1" and the others are "0"), the display monitor 8 displays an image as shown in FIG. 2D. In this case, a portion where two or more color components overlap is displayed as a mixed color. Therefore, red and blue overlapping areas will be displayed in magenta, red and green overlapping areas in yellow, blue and green overlapping areas in cyan, and areas where all three colors overlap will be displayed in white. .
So from the perspective of the observer, from the front to the back, red,
If objects are arranged in the order of green and blue, when the colors of the objects are mixed and displayed as shown in FIG. 2D, it is not possible to determine their context.

Therefore, conventionally, when writing to image memory, the front and back of each object was fixed in advance (for example, a red object was placed at the front, a blue object at the back), and the front and back relationships were set using hardware or software. Eventually, images such as those shown in Fig. 3 A to C were written to the respective screen memory areas. According to this, as shown in Figure 4A, only the object in the foreground is displayed in the overlapping part, so
It is easy to understand their context. However, with this method, information about objects behind objects that are hidden by objects in the foreground is not recorded in memory, so for example, when the red object in the foreground is erased, the objects behind it do not appear, as shown in Figure 4 (b). The disadvantage is that the image becomes

In contrast to such conventional devices, the present inventors suppressed the display signal of the object behind by the display signal of the object in the front, as shown in FIG. 5, so that the object in the front calmed the object behind. In addition to obtaining a display image as shown in Figure 4A, he invented and applied for a display device that, when an object in the foreground, for example a red object, is erased, an object behind it appears and a display image as shown in Figure 6 can be obtained. .

That is, in FIG. 5, the image signal in the screen memory area 2 is converted into an analog signal by the D/A converter 5 and transmitted to the display monitor 8 as it is, but "1" indicating the presence of an image is output from the screen memory area 2. When this is done, it is directly transmitted to the inverter 12 via the inverter 11 or the OR circuit 13, the inverters 11 and 12 output "0", the AND gates 9 and 10 are turned off, and the screen memory area 3, The output signal of 4 is suppressed. Further, when "1" is output from the screen memory area 3, the AND gate 10 is similarly turned off and the output signal from the screen memory area 4 is suppressed. However, with this method, the suppression signal for the rear object is either "1" or "0", and the part of the rear object with no object in front can be seen, but the part that is softened by the object in the front cannot be seen. Become.

However, in some cases, it may be required to see through objects in the foreground to see objects in the back.

By the way, as shown in FIG. 7, when two objects in front (distance) and behind (distance) are displayed in monochrome with n bits each, the image memory 1' is simply When the image signals written in the screen areas 2' and 3' are added by the adder 14, the overlapping portion becomes the sum of the signals output from the screen areas 2' and 3', This is D/A converter 1
5, it is converted into analog data and displayed on the display monitor 16 even brighter. Therefore, the seventh
With the configuration shown in the figure, the object in the foreground does not have a sense of transparency; rather, the bright part appears to be a third object (or area).

Let us now consider what it means to be able to see through objects in general using Figure 8. In Fig. 8, the brightness of an object at a distance from the observer M _{is 1} , the light transmittance is T ₁ (0T ₁ <1),
The brightness of an object at a distance (distance < distance)
₂ , and let E be the intensity of light measured by the observer for the overlapping part, then E=I ₁ +T ₁ I ₂ ...(1). If the object is completely opaque, T ₁ =0, and the greater the transparency, the closer T ₁ is to 1.
Therefore, if it is possible to obtain a display device in which the overlapping portion outputs the relationship as shown in equation (1) above,
It can be seen that objects in the rear can be seen in a translucent state from objects in front, which is an object of the present invention.

Therefore, it is an object of the present invention to provide an image display control device that makes this possible. For this purpose, in the image display control device of the present invention, when a plurality of objects to be displayed are located in front and behind each other, a storage means for storing image information of each of these objects, and a composite image of these objects are displayed. In an image display device having a display means, an image signal reduction means receives the output of the storage means and reduces a brightness value of an image of an object located in the rear by comparing it with a brightness value of an image of an object located in the front, and a data selector. means for transmitting a transparency signal based on the output of the image signal reduction means to one of the input signals of the data selection means, and inputting the transparency signal from the data selection means to the display means in accordance with image information of the object; It is characterized by the following.

An embodiment of the present invention will be described based on FIG. 9.

In the figure, 20 is an image memory, 21 and 22 are screen memory areas, and the screen memory area 21
An image signal 21-0 of an object at a distance is stored in the screen memory area 22, and an image signal 22-0 of an object at a distance is stored in the screen memory area 22. Here distance<distance. 23 is a data selector to which the output signal I ₂ from the screen memory area 22 and the output signal from the multiplier 24 are transmitted.
This multiplier 24 multiplies the output signal I ₂ from the screen memory area 22 by a constant T ₁ , where the constant T ₁ is the transmittance of the object and T ₁ <1.
Now, if the brightness of the object is I ₁ and the brightness of the object is I ₂ , the output of the multiplier 24 will be T ₁ ×I ₂ . 25 is an OR circuit which outputs "1" when at least one bit of the n-bit output signal outputted from the screen memory area 21 is "1", and the data selector 23 is transmitted from the multiplier 24. Acts to output the input signal. 26 is an adder, 27 is a D/A converter, and 28 is a display monitor.

Therefore, from the screen memory area 21, n of the object
When the bit image signal is not output, the OR circuit 25 outputs "0", so the data selector 2
3 outputs the n-bit output signal from the screen memory area 22 to the adder 26 as is. However, when the image signal of the object is output from the screen memory area 21, the OR circuit 25 outputs "1", the data selector 23 outputs T ₁ ×I ₂ transmitted from the multiplier 24, and the adder 26 to communicate. As a result, the adder 26 outputs I ₁ +T ₁ ×I ₂ (see equation (1) above), which is the sum of this T ₁ ×I ₂ and I ₁ output from the screen memory area 21, and this is the D/ The signal is converted into an analog signal by the A converter 27 and displayed on the display monitor 28. Therefore, the portion of the object behind the object is displayed on the display monitor 28 in a transparent manner.

Another embodiment of the present invention will be described based on FIG.

FIG. 10 shows an example where the transmittance T of the object in front varies depending on the location. Therefore, the image memory 29 has a screen memory area 3 for the object.
In addition to the screen memory area 32 for 0 and objects, a screen memory area 31 is provided in which the transmittance of the object is stored. In this screen memory area 31, the transmittance of each pixel of the object is written in n' bits. Therefore, the display monitor 28
When displaying an object in screen memory area 3
1 is also read out at the same time, and its transmittance T is added to the multiplier 24.
By outputting to , the object can be displayed transparently even if the transmittance of the object changes depending on the location.

A third embodiment of the present invention will be described based on FIG. 11.

This figure 11 shows the case where these are arranged in the order of object, object, object from the front.
The object has a transmittance T ₁ and the object has a transmittance T ₂ (0<T ₁ , T ₂ <1). In this case, the object (distance) is the same as in the previous embodiment.
For objects (distance, distance<distance), there are 4 parts: a part with no other object in front, a part with an object, a part with an object, and a part with an object.
There are two cases. Therefore, the configuration is such that these four states can be selected for the object by the second data selector 42.

In FIG. 11, a screen memory area 33 stores image information for an object having a brightness I ₁ , a screen memory area 34 stores image information for the object, and a screen memory area 35 stores image information for the object. has been done. Multiplier 36
is the product T ₁ × of the input transmittance T 1 of the object and the brightness _{I 2} of the object output from the screen memory area 34
I ₂ is output. and the first data selector 4
1, T ₁ ×I ₂ transmitted from this multiplier 36 and image information of the object transmitted from the screen memory area 34 are transmitted. And screen memory area 3
“1” indicating the presence of an object from 3 is an OR circuit 43
When applied to the first data selector 41
outputs T ₁ ×I ₂ transmitted from the multiplier 36,
When "0" is applied, the image information transmitted from the screen memory area 34 is output as is.

The transmittance T ₁ of the object is input to the multiplier 37, and the product T ₁ ×I ₃ with the brightness I ₃ of the object output from the screen memory area 35 is output.

The transmittance T ₂ of the object is input to the multiplier 38, and the product T ₂ ×I ₃ with the brightness I ₃ of the object output from the screen memory area 35 is output.

The transmittances T ₁ and T ₂ are input to the multiplier 39, and the product T ₁ ×T ₂ is input to the multiplier 40, which outputs T ₁ ×T ₂ ×I ₃ .

The second data selector 42 includes the multiplier 3
T ₁ ×I ₃ , T ₂ ×I ₃ outputted from 7, 38, 40,
T ₁ ×T ₂ ×I ₃ and image information of the object output from the screen memory area 35 are transmitted. Then, "1" is output from the OR circuit 43 indicating the presence of an object.
is applied, the signal transmitted from the multiplier 37 is
OR circuit 4 outputs T ₁ × I ₃ and indicates the existence of an object
When "1" is applied from the multiplier 40, the multiplier 40 outputs T ₂ ×I ₃ transmitted from the multiplier 38, and when "1" is applied from each of the OR circuits 43 and 44 indicating the presence of an object, the multiplier 40 T ₁ ×T ₂ × transmitted from
I ₃ is output, and when "0" is applied from both OR circuits 43 and 44, the image information transmitted from the screen memory area 35 is output as is. Then, the output of the screen memory area 33, the output of the first data selector 41, and the output of the second data selector 42 are added by the adder 45, and the D/A converter 27
The signals are converted into analog signals, and the objects are displayed on the display monitor 28 in a semi-transparent state.

Generally, when m objects (m≧1) are lined up one after the other, the intensity of the light that reaches the observer's eyes is E, the brightness of the i-th object from the front (1≦i≦m) is Ii, and the transmitted light is If the rate is Tj, It is. However, T ₀ =1 0≦Ti<1: Portion where object i is present Ti=1: Portion where object i is not present. In this way, even when there are a large number of objects, the structure can be configured in the same way. Note that although the above explanation has been given using a monochrome example, it can of course also be applied to a color display.

As described above, according to the present invention, when objects exist in front and back, it is possible to display a rear object by making a part of the front object semi-transparent. Therefore, for example, in the case of designing a laminated printed board, it is possible to display the positional relationship of patterns in each layer, making it possible to design through-hole positions with great accuracy, and so on. This provides a meaningful display device that can be used.

[Brief explanation of the drawing]

Fig. 1 is a conventional display device, Figs. 2 to 4 are illustrations of its operating state, and Figs. 5 and 6 are a display device that displays a state in which it is calmed by an object in front, and its operating state. 7 is a display device in which two images are superimposed, FIG. 8 is an explanatory diagram of a transparent state, FIG. 9 is a configuration diagram of an embodiment of the present invention, FIG.
FIG. 1 is a diagram showing the configuration of different embodiments of the present invention. In the figure, 20 is an image memory, 21 and 22 are screen memory areas, 23 is a data selector, 24 is a multiplier, 25 is an OR circuit, 26 is an adder, and 27 is a D/
A converter, 28 is a display monitor, 29 is an image memory, 30 to 32 are screen memory areas, 33 to 35 are screen memory areas, 36 to 40 are multipliers, 41 is a first data selector, 42 is a second data -Selector, 43 and 44 are OR circuits, and 45 is an adder.

Claims (1)

[Claims] 1. When a plurality of objects to be displayed are located in front and behind each other, an image display device having a storage means for storing image information of each of these objects and a display means for synthesizing and displaying images of these objects, wherein the storage means image signal reduction means and data selection means are provided for reducing the brightness value of an image of an object located at the rear by comparing it with the brightness value of an image of an object located at the front. An image display control device characterized in that the transparency signal based on the output of the image signal reduction means is transmitted to the object, and the transparency signal is inputted from the data selection means to the display means in accordance with image information of the object. .