JP2577267B2 - Image processing device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a raster scan type three-dimensional image processing apparatus having a graphic processing function.

[Conventional technology]

In a three-dimensional image processing apparatus, depth skew processing is used to represent the depth direction of display. In this processing, luminance conversion is performed on a device coordinate system that is a final coordinate system of display.

[Problems to be solved by the invention]

With the above technology, when a plurality of independent figures are displayed at the same time, the luminance is determined by the position of the independent figures in the device coordinate system. Was lacking.

[Means for solving the problem]

SUMMARY OF THE INVENTION In view of the above, the present invention provides a pre-processing unit that generates commands and data for a graphic to be displayed, an address selection circuit that selects a process based on the graphic command, and a depth control unit that controls a part of the address selection circuit. A queue control circuit, a memory for storing a microprogram, a microprogram control circuit for controlling the memory, and a depth skew processing circuit for performing a depth skew process by an output of the microprogram control circuit, and having a depth skew control circuit. Thus, it is possible to select to perform the depth skew processing for each independent figure or for all the displayed figures.

[Action]

According to the configuration described above, it is possible to selectively use the application to perform the depth skew processing for each independent graphic or for all the graphics on the display screen.

〔Example〕

 Hereinafter, embodiments of the present invention will be described with reference to the drawings.

In FIG. 1, reference numeral 1 denotes a pre-processing unit for generating the type of line segment to be displayed and its coordinate value, and the output format is composed of a plurality of bits of command and data.

Reference numeral 2 denotes an address selection circuit that selects an execution address of the microprogram storage memory 4 based on an output of the preprocessing unit 1, and is configured by a memory, a selector, a register, and the like.

Reference numeral 3 denotes a depth skew control circuit which takes in the value output from the pre-processing unit 1 at the timing of the output signal of the microprogram control circuit 5 and determines the presence or absence of a depth skew and the depth skew processing mode based on the value. It is connected to the address selection circuit 2 and switches the execution address of the microprogram.

Reference numeral 4 denotes a microprogram storage memory for determining the operation of the depth skew processing circuit 6, which outputs the output of the address selection circuit 2 to the microprogram control circuit 5 as an address.

Reference numeral 5 denotes a register for storing output data of the microprogram storage memory 4, which is sequentially read in accordance with a control clock, and the output of which is used as a microprogram instruction to control the depth skew processing circuit 6 and the depth skew control circuit 3.

Reference numeral 6 denotes a circuit for performing a depth skew process in accordance with the output of the microprogram control circuit 5, which converts the coordinate values in the depth direction of the display into luminance.

FIG. 2 is a layout diagram of a memory of the address selection circuit 2.

The memory addresses are mapped as shown in the figure by the depth skew processing method.

As a processing method, whether depth skew is performed (depth skew ON) or not (depth skew processing FF), normalized coordinate system (NDC) or device coordinate system (DC)
Whether to perform depth skew processing on the above.

That is, when depth skew processing is performed on all display graphics as in the past, depth skew processing is performed in DC, and when depth skew processing is performed for each independent graphic, depth skew processing is performed in NDC. .

FIG. 2 is a reference diagram, and it is also possible to add a depth skew correction mode and the like. This layout is largely mapped to the four by the depth skew control circuit 3. FIG. 3 is a preferred explanatory diagram of the depth skew process.

In this figure, the figure 1 and the figure 2 show the depth direction (Z-axis coordinate) when defined in the world coordinate system (hereinafter WC), and the right side with respect to the W axis is closer to the viewpoint. By performing coordinate conversion from WC to NDC, the coordinate values of the figure are normalized. This coordinate value normalization process is necessary to cut out a three-dimensional display area desired by the user from the three-dimensional world coordinate system and display only that area. FIG. 3 shows only the Z-axis of the NDC relating to the present invention. Further, when converted into DC corresponding to the display screen, FIG. 1 becomes a position close to the viewpoint with respect to FIG.
The present invention selects the case where the normalization processing is performed for each figure and the depth skew processing is performed in the NDC, or the case where the normalization processing is performed for the entire figure to be displayed and the depth skew processing is performed in the DC. It is configured to be able to.
Here, when depth skew processing is performed in DC as in the processing mapped in the fourth place in FIG. 2, the Z value of each figure is subjected to luminance conversion as shown in B in the figure.

That is, Z1 and Z2 of FIG. 1 are respectively set to I1 and I2, and Z1 and Z2 of FIG.
3 and Z4 are converted to I3 and I4 respectively, so Figure 1 and Figure 2
Then, the brightness, that is, the brightness is different even in the same front surface.

In other words, on the Z axis, the luminance of the graphic located far from the viewpoint has a lower value than the luminance of the graphic located near the viewpoint. This is a depth skew process performed on all conventionally used display graphics.

On the other hand, when the depth skew process is performed in the NDC as in the process mapped in the third place in FIG. 2, each figure is +1 to −1 on the Z axis of the NDC as shown in FIG. Is normalized to fall within the range of
Since the luminance is converted as indicated by A in the figure, the front surfaces (Z1, Z3 in terms of coordinate values) of FIG. 1 and FIG. 2 have the same luminance. That is, depth skew is applied to each figure.

In other words, on the Z axis, the same luminance can be given to a figure located far from the viewpoint as a figure located near the viewpoint.

This is because all figures are normalized from -1 to +1 in NDC, and luminance conversion is performed on the value.

〔The invention's effect〕

As is apparent from the above description, the present invention has the depth skew control circuit, so that the depth skew processing can be switched, and the optimum depth skew processing can be performed according to the application.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIG.
FIG. 3 is a layout diagram of a memory of the address selection circuit 2, and FIG. DESCRIPTION OF SYMBOLS 1 ... Pre-processing part 2 ... Address selection circuit 3 ... Depth skew control circuit 4 ... Microprogram storage memory 5 ... Microprogram control circuit 6 ... Depth skew processing circuit

Claims (1)

(57) [Claims] A preprocessing unit for generating a command and data of a graphic to be displayed; an address selection circuit for selecting a process according to the command of the graphic; and a depth cue control circuit for controlling a part of the address selection circuit. A memory for storing a microprogram, a microprogram control circuit for controlling the memory, and a depth skew processing circuit for performing a depth skew process based on an output of the microprogram control circuit. Based on the command output from the unit, whether to perform depth skew processing in the device coordinate system or to perform depth skew processing in the normalized coordinate system, and perform depth skew processing in the device coordinate system Normalize the whole figure to be displayed, When performing depth queuing in a normalized coordinate system to normalize each figure,
An image processing apparatus, wherein an execution address of the microprogram storage memory is switched via the address selection circuit.