GraphicsV 27 (changes)
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GraphicsV
» GraphicsV 27
Graphics Vector (42)
| Entry | |
|---|---|
| R0 | Left edge of clipping rectangle (inclusive) |
| R1 | Top edge of clipping rectangle (inclusive) |
| R2 | Right edge of clipping rectangle (exclusive) |
| R3 | Bottom edge of clipping rectangle (exclusive) |
| R4 | Bits 0-15: 27 (reason code) |
| Bits 16-23: Overlay number | |
| Bits 24-31: Driver number | |
| R5 | Scaled width |
| R6 | Scaled height |
| R7 | Aspect ratio to use if image size needs adjusting |
| Top 16 bits = width | |
| Bottom 16 bits = height |
| Exit | |
|---|---|
| R0 | Actual left edge of clipping rectangle |
| R1 | Actual top edge of clipping rectangle |
| R2 | Actual right edge of clipping rectangle |
| R3 | Actual bottom edge of clipping rectangle |
| R4 | 0 |
| R5 | Actual scaled width |
| R6 | Actual scaled height |
| - | All other registers preserved |
Use
Adjusts the scale and clipping rectangle for an overlay. R5 and R6 specify the size the overlay should be scaled to (in screen pixels). Then, the clipping rectangle defined by R0-R3 will be used to crop the displayed area. This is also specified in units of screen pixels. For rotated overlays, the values correspond to the rotated form, i.e. as it will appear on screen. Rounding errors or other hardware limits may prevent the chosen values from being used, in which case the driver will make the necessary adjustments (while maintaining the indicated aspect ratio) and return the actual values used.
See also
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