Difference between revisions of "Sprite Attribute Upload"
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(Core 2.00.22 changes.) |
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{{Port | {{Port | ||
|Number=$xx57 | |Number=$xx57 | ||
| − | |ShortDesc=Uploads sprite positions, visibility and effect flags. | + | |ShortDesc=Uploads sprite positions, visibility, colour type and effect flags. |
|PortMask=%---- ---- 0101 0111 | |PortMask=%---- ---- 0101 0111 | ||
|Readable=No | |Readable=No | ||
| Line 7: | Line 7: | ||
|Subsystem=Sprites | |Subsystem=Sprites | ||
}} | }} | ||
| − | Uploads attributes of the sprite slot selected by {{PortNo|$303B}}. Attributes are in 4 byte blocks sent in the following order; after sending 4 bytes the address auto-increments to the next sprite. This auto-increment is independent of other sprite ports. The 4 bytes are as follows: | + | Uploads attributes of the sprite slot selected by {{PortNo|$303B}}. Attributes are in 4-5 byte blocks sent in the following order; after sending 4 or 5 bytes the address auto-increments to the next sprite. This auto-increment is independent of other sprite ports. The 4-5 bytes are as follows: |
Byte 1 is the low bits of the X position. Legal X positions are 0-319 if sprites are allowed over the border or 32-287 if not. The MSB is in byte 3. | Byte 1 is the low bits of the X position. Legal X positions are 0-319 if sprites are allowed over the border or 32-287 if not. The MSB is in byte 3. | ||
| − | Byte 2 is the Y position. Legal Y positions are 0-255 if sprites are allowed over the border or 32-223 if not. | + | Byte 2 is the Y position. Legal Y positions are 0-255 if sprites are allowed over the border or 32-223 if not (with "core 2.00.22" there's now Y8 bit in b0 of byte 5, allowing for positions 0-511, but I'm not sure at this moment what are legal values). |
Byte 3 is bitmapped: | Byte 3 is bitmapped: | ||
| Line 28: | Line 28: | ||
|} | |} | ||
| − | Byte 4 is | + | Byte 4 is bitmapped: |
{|class="wikitable" | {|class="wikitable" | ||
! Bit !! Description | ! Bit !! Description | ||
| Line 34: | Line 34: | ||
| 7 || Enable visibility | | 7 || Enable visibility | ||
|- | |- | ||
| − | | 6 || | + | | 6 || If 1, the optional 5th attribute byte should follow. If 0, only four attribute bytes are expected. |
|- | |- | ||
| 5-0 || Pattern index ("Name") | | 5-0 || Pattern index ("Name") | ||
| + | |} | ||
| + | |||
| + | Optional (when bit 6 is set in byte 4) byte 5 is bitmapped: | ||
| + | {|class="wikitable" | ||
| + | ! Bit !! Description | ||
| + | |- | ||
| + | | 7 || If 1, the pattern will be treated as 4-bit colour one (128 bytes), 0 is for 8-bit colour patterns (256 bytes) | ||
| + | |- | ||
| + | | 6 || Chooses top/bottom part of pattern slot (for 4-bit colour patterns) | ||
| + | |- | ||
| + | | 5 || Reserved, use always 0 | ||
| + | |- | ||
| + | | 4-3 || x-axis scale factor: %00 = 1x (16 pixels), %01 = 2x, %10 = 4x, %11 = 8x (128 pixels) | ||
| + | |- | ||
| + | | 2-1 || y-axis scale factor: %00 = 1x (16 pixels), %01 = 2x, %10 = 4x, %11 = 8x (128 pixels) | ||
| + | |- | ||
| + | | 0 || MSB of Y coordinate | ||
|} | |} | ||
Revision as of 03:49, 20 December 2018
| Number | $xx57 |
|---|---|
| Decimal | |
| Short desc. | Uploads sprite positions, visibility, colour type and effect flags. |
| Bit Mask | %---- ---- 0101 0111 |
| Readable | No |
| Writable | Yes |
| Subsystem | Sprites |
Uploads attributes of the sprite slot selected by Sprite Status/Slot Select ($303B / 12347). Attributes are in 4-5 byte blocks sent in the following order; after sending 4 or 5 bytes the address auto-increments to the next sprite. This auto-increment is independent of other sprite ports. The 4-5 bytes are as follows:
Byte 1 is the low bits of the X position. Legal X positions are 0-319 if sprites are allowed over the border or 32-287 if not. The MSB is in byte 3.
Byte 2 is the Y position. Legal Y positions are 0-255 if sprites are allowed over the border or 32-223 if not (with "core 2.00.22" there's now Y8 bit in b0 of byte 5, allowing for positions 0-511, but I'm not sure at this moment what are legal values).
Byte 3 is bitmapped:
| Bit | Description |
|---|---|
| 4-7 | Palette offset, added to each palette index from pattern before drawing |
| 3 | Enable X mirror |
| 2 | Enable Y mirror |
| 1 | Enable rotation |
| 0 | MSB of X coordinate |
Byte 4 is bitmapped:
| Bit | Description |
|---|---|
| 7 | Enable visibility |
| 6 | If 1, the optional 5th attribute byte should follow. If 0, only four attribute bytes are expected. |
| 5-0 | Pattern index ("Name") |
Optional (when bit 6 is set in byte 4) byte 5 is bitmapped:
| Bit | Description |
|---|---|
| 7 | If 1, the pattern will be treated as 4-bit colour one (128 bytes), 0 is for 8-bit colour patterns (256 bytes) |
| 6 | Chooses top/bottom part of pattern slot (for 4-bit colour patterns) |
| 5 | Reserved, use always 0 |
| 4-3 | x-axis scale factor: %00 = 1x (16 pixels), %01 = 2x, %10 = 4x, %11 = 8x (128 pixels) |
| 2-1 | y-axis scale factor: %00 = 1x (16 pixels), %01 = 2x, %10 = 4x, %11 = 8x (128 pixels) |
| 0 | MSB of Y coordinate |