Image processing device, image processing method and storage medium for storing image processing programs

An image processing device for generating image data by conducting rendering processing, for a plurality of polygons, said image processing device comprising:

• a polygon data generating section for generating polygon data containing, at the least, two-dimensional co-ordinates in a display screen, a Z value (depth value) indicating a depth in the display screen, texture co-ordinates and attribute data indicating the type of polygon, for polygons positioned in a display screen, said attribute data including a semi-transparent polygon, an opaque polygon, a polygon containing transparency portion, and a polygon not containing transparency portion;
• a polygon buffer memory for storing said polygon data for a frame, said polygon data to be stored separately according to said attribute data;
• a frame buffer memory for storing said image data;
• a Z value buffer memory for storing said Z values for pixels corresponding to the image data stored in said frame buffer memory;
• a texture map memory for storing texture data for said polygons in a region corresponding to said texture co-ordinates;
• and a rendering section, which is supplied within said polygon data in a prescribed order of priority of said attribute data, and which determines a Z value for a pixel in said polygons form said polygon data, compares the Z value with a Z value stored in said Z value buffer memory, and reads out texture data corresponding to the texture co-ordinates for said pixel and generates image data containing colour data from said texture data, if the Z value for said pixel is the smaller,
• wherein said prescribed order is set such that the generation of the image date for pixels in the polygons is carried for the semi-transparent polygon after the opaque polygon, and is carried out for the polygon containing transparency portion after the polygon not containing transparency portion.

An image processing method for generating image data by conducting rendering processing for a plurality of polygons, said image processing method comprising the steps of:

• generating polygon data containing, at the least, two-dimensional co-ordinates in a display screen, a Z value (depth value) indicating a depth in the display screen, and attribute data indicating the type of polygon, for polygons positioned in a display screen, said attribute data including a semi-transparent polygon, an opaque polygon, a polygon containing transparency portion, and a polygon not containing transparency portion;
• storing said polygon data for a frame in a polygon buffer memory separately according to said attribute data;
• and
• generating said image data for pixels in said polygons from said polygon data, in a prescribed order of priority relating to said attribute data in said polygon data,
• wherein said prescribed order is set such that the generation of the image data for pixels in the polygons is carried out for the semi-transparent polygon after the opaque polygon, and is carried out for the polygon containing transparency portion after the polygon not containing transparency portion.

A computer-readable storage medium for storing an image processing program for generating image data by conducting rendering processing for a plurality of polygons, said image processing program being configured to operate a computer to:

• generate polygon data containing, at the least, two-dimensional co-ordinates in a display screen, a Z value (depth value) indicating a depth in the display screen, and attribute data indicating the type of polygon, for polygons positioned in a display screen, said attribute data including a semi-transparent polygon, an opaque polygon, a polygon containing transparency portion, and a polygon not containing transparency portion;
• store said polygon data for a frame in a polygon buffer memory separately according to said attribute data;
• and
• generate said image data for pixels in said polygons from said polygon data, in a prescribed order of priority relating to said attribute data in said polygon data, wherein said prescribed order is set such that the generation of the image data for pixels in the polygons is carried out or the semi-transparent polygon after the opaque polygon, and is carried out for the polygon containing transparency portion after the polygon not containing transparency portion.

An image processing device, comprising:

• a polygon data generating portion for generating polygon data containing attribute data indicating the type of said polygons, said attribute data including an opaque polygon, an opaque polygon containing transparency portion, a semi-transparent polygon, and a semi-transparent polygon containing transparency portion;
• a polygon buffer memory for storing said polygon data, said polygon data to be stored separately, according to said attribute data;
• a rendering section for reading out said polygon data from said polygon buffer memory in an order of priority determined on the basis of said attribute data;
• and
• a frame buffer for receiving image data from said rendering section, wherein said order of priority is set in the order of an opaque polygon, an opaque polygon containing transparency portion, a semi-transparent polygon, then a semi-transparent polygon containing transparency portion.

An image processing method, said method comprising:

• generating polygon data for a plurality, of polygons, said polygon data containing attribute data indicating the type of said polygons, said attribute data including an opaque polygon, an opaque polygon containing transparency portion, a semi-transparent polygon, and a semi-transparent polygon containing transparency portion;
• storing said polygon data in a polygon buffer memory;
• reading out said polygon data from said polygon buffer memory in an order of priority determined on the basis of attribute data;
• and
• writing image data based on said polygon data to a frame buffer in the order that said polygon data is read out, wherein said order of priority is set in the order of an opaque polygon, an opaque polygon containing transparency portion, a semi-transparent polygon, then a semi-transparent polygon containing transparency portion.

A computer-readable storage medium for storing an image processing program, said image processing program being configured to operate a computer to:

• generate polygon data containing attribute data, said attribute data indicating for a plurality of polygons, the type of said polygons, said attribute data including an opaque polygon, an opaque polygon containing transparency portion, a semi-transparent polygon, and a semi-transparent polygon containing transparency portion;
• store said polygon data in a polygon buffer memory;
• read out said polygon data from said polygon buffer memory in an order of priority determined on the basis of said attribute data;
• and
• write image data based on said polygon data to a frame buffer in the order that said polygon data is read out, wherein said order of priority is set in the order of an opaque polygon, an opaque polygon containing transparency portion, a semi-transparent polygon, then a semi-transparent polygon containing transparency portion.