sejo
/
compudanzas
2
3
Fork 3
Code Issues Pull Requests Projects Releases Wiki Activity

screen device and minor formatting

This commit is contained in:
sejo 2024-03-14 20:37:34 +01:00
parent 1c3ed6c366
commit f4c8f22e31
3 changed files with 16 additions and 11 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
src/roadmap.gmo
View File

@ -42,6 +42,7 @@ implement the following concepts as {coloring computers}:
* make a folder of examples
* whenever we mention the theme loading, link to the suggested palette.
* replace intro to colors with a table.
* include uxn5 in the web tutorial so that code can be run from there
=> https://git.sr.ht/~rabbits/uxn5 uxn5

2
src/uxn_tutorial_day_1.gmo
View File

@ -276,7 +276,7 @@ we're talking about a device address, 18, but what does it mean?
looking at the devices table from the varvara reference, we can see that the device with address 1 in the high nibble is the console (standard input and output), and that the column with address 8 in the low nibble corresponds to the "write" port.
=> https://wiki.xxiivv.com/site/varvara.html#console varvara: console device
=> https://wiki.xxiivv.com/site/varvara.html#console XXIIVV — varvara console device
so, device address 18 corresponds to "console write", or standard output.

24
src/uxn_tutorial_day_2.gmo
View File

@ -165,6 +165,8 @@ in uxntal examples we can see its labels defined as follows:
|00 @System &vector $2 &pad $6 &r $2 &g $2 &b $2
```
=> https://wiki.xxiivv.com/site/varvara.html#system XXIIVV — varvara system device
we will ignore the first elements for the moment, and focus on the color components.
## system colors
@ -197,10 +199,10 @@ how would we read what those literal shorts mean?
we can read each of the colors vertically, from left to right. therefore:
* color0 would have: red: 2, green: 1, blue: 1 ( #221111 in hex color notation, brown)
* color1 would be red: e, green: e, blue: e ( #eeeeee in hex color notation, white )
* color2 would be red: e, green: b, blue: 2 ( #eebb22 in hex color notation, amber )
* color3 would be red: f, green: 8, blue: e ( #ff88ee in hex color notation, pink )
* color0 would have: red: 2, green: 1, blue: 1 (#221111 in hex color notation, brown)
* color1 would be red: e, green: e, blue: e (#eeeeee in hex color notation, white)
* color2 would be red: e, green: b, blue: 2 (#eebb22 in hex color notation, amber)
* color3 would be red: f, green: 8, blue: e (#ff88ee in hex color notation, pink)
if we run the program now we'll see a brown screen, instead of black as what we had before.
@ -208,7 +210,7 @@ try changing the values of color0, i.e. the first column, and see what happens :
# the screen device
as a recap: we mentioned that the screen device can only show four different colors at a given time, and that these colors are numbered from 0 to 3. we set these colors using the corresponding ports in the system device.
the screen device can only show four different colors at a given time, and these colors are numbered from 0 to 3. we set these colors using the corresponding ports in the system device.
now let's discuss the screen device and start using it!
@ -217,15 +219,17 @@ now let's discuss the screen device and start using it!
in uxntal programs for the varvara computer you will be able to find the labels corresponding to this device ports as follows:
```
|20 @Screen [ &vector $2 &width $2 &height $2 &auto $1 &pad $1 &x $2 &y $2 &addr $2 &pixel $1 &sprite $1 ]
|20 @Screen &vector $2 &width $2 &height $2 &auto $1 &pad $1 &x $2 &y $2 &addr $2 &pixel $1 &sprite $1
```
=> https://wiki.xxiivv.com/site/varvara.html#screen XXIIVV — varvara screen device
these are the ports in list format:
* vector (2 bytes)
* width of the screen (2 bytes)
* height of the screen (2 bytes)
* auto (1 byte)
* auto byte (1 byte)
* x coordinate (2 bytes)
* y coordinate (2 bytes)
* memory address (2 bytes)
@ -238,11 +242,11 @@ we will cover the rest of the ports today!
## foreground and background
the screen device has two overlayed layers of the same size, the foreground and the background.
the screen device has two overlaid layers of the same size, the foreground and the background.
whatever is drawn over the foreground layer will cover anything that is drawn in the same position in the background layer.
whatever is drawn in the foreground layer will cover anything that is drawn in the same position in the background layer.
in the beginning the foreground layer is completey transparent: a process of alpha blending makes sure that we can see the background layer.
in the beginning, the foreground layer is completey transparent: a process of alpha blending makes sure that we can see the background layer.
# drawing a pixel