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

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VDP1 User's Manual / Chapter 7 Commands

■ 7.5 Rectangle sprite drawing command

The Rectangle Sprite Draw command draws a character pattern in the framebuffer. When drawing, you can flip the character pattern upside down, flip it horizontally, zoom in / out, or stretch it to the specified coordinates.
This is a rectangular sprite drawing command when the end bit is 0B and the command selection bit is 0001B. When the zoom point is 0000B, it is defined by specifying two coordinates. When the value is other than 0000B, the fixed point is specified.
Rectangular sprites cannot be rotated 90 °. If you want to rotate it 90 °, specify it with the transform sprite drawing command.

● Specify two coordinates (rectangular sprite drawing command)

The contents of the command table for specifying two coordinates are as follows.

bit 15 14 13 12 11 Ten 9 8 7 6 5 4 3 2 1 0 CMDCTRL +00 0 JP 0 0 0 0 0 0 Dir 0 0 0 1 CMDLINK +02 LINK designation / 8H 0 0 CMDPMOD +04 MO 0 0 0 Pc Cl Cm Me EC SP Color mode Color calculation CMDCOLR +06 Color bank, color look-up table / 8H (LSB fixed to 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 CMDXC +14 Sign extension Vertex (C), X coordinate (XC) CMDYC +16 Sign extension Vertex (C), Y coordinate (YC) +18 + 1A CMDGRDA + 1C Gouraud shading table / 8H 【note】 Is ignored (don't care)

The two-point coordinate specification of the rectangular sprite drawing command is defined as follows.

Setting the end bit to 0B and the command selection bit to 0001B results in a rectangular sprite drawing command. Specify the jump format. When the jump format is assign or call, divide the address of the command table to be processed next by 8H and set it to CMDLINK. Set the zoom point to 0000B. Two coordinates are specified. Set the reading direction of the character pattern. You can draw by flipping vertically or horizontally by specifying the reading direction. If the inversion is specified twice by specifying the read direction and specifying the vertices (A) (CMDXA, CMDYA) and vertices (C) (CMDXC, CMDYC), the inversions are canceled and the orientation returns to the original. .. Set high speed shrink. Specify precision priority or speed priority. Set pre-clipping. Consider the clipping area and the drawing position of the part, and specify whether it is enabled or disabled. Specifies the user clipping enabled bit and the clipping mode. Specifies whether user clipping is outside or inside in clipping mode. Set mesh enabled, end code disabled, and transparent pixel disabled. Sets the MSB on for shading or windowing in VDP2. Sets the color mode that defines the character pattern. Specify the color bank when the color mode is color bank mode. In lookup table mode, define the color lookup table address by dividing it by 8H. Specifies the color operation. Color calculation is valid in RGB mode. If you do not want to perform color calculation, specify replacement. When performing Gouraud shading processing, specify the address of the Gouraud shading table by dividing it by 8H. Gouraud shading processing is effective when using RGB mode. Divide the address of the character pattern table by 8H and define it in CMDSRCA. Define the horizontal and vertical of the character size defined in the character pattern table in CMDSIZE. The horizontal size defines the value divided by 8. Define the upper left coordinates of the area to be drawn at the vertices (A) (CMDXA, CMDYA) and the lower right coordinates at the vertices (C) (CMDXC, CMDYC). You can enlarge / reduce, expand / contract, and draw by specifying the vertex (A) and vertex (C). Also, if (XA of vertex (A))> (XC of vertex (C)), the shape will be flipped horizontally. If (YA of vertex (A))> (YC of vertex (C)), the shape will be upside down. Note: If vertex A and vertex C are set to the same coordinates, they will be drawn in 1 pixel.

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