<45/54>VDP1 User's Manual/

★ HARDWARE Manual ★ VDP1 User's Manual ★ Chapter 7 Command

▲ Back ｜ Forward ▼

VDP1 User's Manual/Chapter 7 Commands

■7.4 Standard sprite drawing commands

The fixed sprite drawing commands draw character patterns into the frame buffer. When drawing, you can draw the character pattern upside down or horizontally at the specified coordinates.
When the end bit is 0B and the command selection bit is 0000B, it is a fixed sprite drawing command. Fixed sprites cannot be rotated 90 degrees. If you want to rotate the sprite by 90 degrees, specify it using the transform sprite drawing command.
The contents of the command table are as follows:

bit 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 CMDCTRL +00 0 JP 0 0 0 0 0 0 Dir 0 0 0 0 CMDLINK +02 LINK specification/8H 0 0 CMDPMOD +04 M.O. 0 0 0 PC Cl Cm Me E.C. SP Color mode color calculation CMDCOLR +06 Color bank, color lookup table/8H (LSB fixed at 00) CMDSRCA +08 Character address/8H CMDSIZE +0A 0 0 Character size X/8 Character size Y/8 CMDXA +0C sign extension Vertex (A), X coordinate (XA) CMDYA +0E sign extension Vertex (A), Y coordinate (YA) +10 +12 +14 +16 +18 +1A CMDGRDA +1C Gouraud shading table/8H 【note】 is ignored (don't care)

The fixed sprite drawing command is defined as follows.

Setting the end bit to 0B and the command selection bit to 0000B makes it a fixed sprite drawing command. Specify the jump format. When the jump format is Assign or Call, divide the address of the next command table to be processed by 8H and set it to CMDLINK. Set the character pattern read direction. By specifying the reading direction, you can reverse the image vertically or horizontally. Set pre-clipping. Specify whether to enable or disable it, considering the clipping area and the drawing position of the part. Specify the user clipping enable bit and clipping mode. Specifies whether user clipping is outside or inside in clipping mode. Set mesh enabled, end code disabled, transparent pixels disabled. Set MSB on for shade or window processing in VDP2. Set the color mode that defines the character pattern. Specifies the color bank when the color mode is color bank mode. When in lookup table mode, divide the color lookup table address by 8H to define. Specify color operation. Color calculation is valid in RGB mode. If you do not want to perform color calculations, specify Replace. When performing Gouraud shading processing, divide the address of the Gouraud shading table by 8H and specify it. Gouraud shading processing is valid in RGB mode. Divide the character pattern table address by 8H and define it in CMDSRCA. Define the width and height of the character size defined in the character pattern table in CMDSIZE. The horizontal size is defined as the value divided by 8. Define the upper left coordinates of the area to be drawn as vertex (A) (CMDXA, CMDYA).

▲ Back ｜ Forward ▼

★ HARDWARE Manual ★ VDP1 User's Manual ★ Chapter 7 Command