Howto:Creating a Font Browser using Nasal and Canvas: Difference between revisions
Jump to navigation
Jump to search
m (https://forum.flightgear.org/viewtopic.php?f=37&t=36946&p=362269#p362150) |
m (https://forum.flightgear.org/viewtopic.php?f=37&t=36946&p=362269#p362269) |
||
Line 18: | Line 18: | ||
Alternatively, it would be possible to render the menubar completely using the Canvas system: [[Howto:Making_a_Canvas_Menubar]] | Alternatively, it would be possible to render the menubar completely using the Canvas system: [[Howto:Making_a_Canvas_Menubar]] | ||
== Proof of Concept == | |||
<syntaxhighlight lang="nasal"> | |||
var (width,height) = (320,160); | |||
var title = 'Font Browser (by downpilot)'; | |||
# create a new window, dimensions are WIDTH x HEIGHT, using the dialog decoration (i.e. titlebar) | |||
var window = canvas.Window.new([width,height],"dialog") | |||
.set('title',title); | |||
## | |||
# the del() function is the destructor of the Window | |||
# which will be called upon termination (dialog closing) | |||
# you can use this to do resource management (clean up timers, listeners or background threads) | |||
#window.del = func() | |||
#{ | |||
# print("Cleaning up window:",title,"\n"); | |||
# explanation for the call() technique at: http://wiki.flightgear.org/Object_oriented_programming_in_Nasal#Making_safer_base-class_calls | |||
# call(canvas.Window.del, [], me); | |||
#}; | |||
# adding a canvas to the new window and setting up background colors/transparency | |||
var myCanvas = window.createCanvas().set("background", canvas.style.getColor("bg_color")); | |||
# Using specific css colors would also be possible: | |||
# myCanvas.set("background", "#ffaac0"); | |||
# creating the top-level/root group which will contain all other elements/group | |||
var root = myCanvas.createGroup(); | |||
# path is relative to $FG_ROOT (base package) | |||
var path = "Fonts/Helvetica.png"; | |||
# create an image child for the texture | |||
var child = root.createChild("image") | |||
.setFile(path) | |||
.setTranslation(100, 10) | |||
.setSize(130, 130); | |||
</syntaxhighlight> |
Revision as of 11:03, 24 February 2020
This article is a stub. You can help the wiki by expanding it. |
Background
No easy way to browse a list of available fonts in the base package
Idea
Implement a simple font browser using Nasal and Canvas
Approach
since FlightGear uses OpenSceneGraph, and since OSG supports TXF , we might use Nasal/Canvas to display a list of fonts and even preview them inside fgfs (?)
To see for yourself, modify the Canvas image example to point to a font file:
If this works, this can be trivially extended to show a list of all fonts including a preview, by adapting this snippet: Canvas_Snippets#Canvas_ScrollArea
Alternatively, it would be possible to render the menubar completely using the Canvas system: Howto:Making_a_Canvas_Menubar
Proof of Concept
var (width,height) = (320,160);
var title = 'Font Browser (by downpilot)';
# create a new window, dimensions are WIDTH x HEIGHT, using the dialog decoration (i.e. titlebar)
var window = canvas.Window.new([width,height],"dialog")
.set('title',title);
##
# the del() function is the destructor of the Window
# which will be called upon termination (dialog closing)
# you can use this to do resource management (clean up timers, listeners or background threads)
#window.del = func()
#{
# print("Cleaning up window:",title,"\n");
# explanation for the call() technique at: http://wiki.flightgear.org/Object_oriented_programming_in_Nasal#Making_safer_base-class_calls
# call(canvas.Window.del, [], me);
#};
# adding a canvas to the new window and setting up background colors/transparency
var myCanvas = window.createCanvas().set("background", canvas.style.getColor("bg_color"));
# Using specific css colors would also be possible:
# myCanvas.set("background", "#ffaac0");
# creating the top-level/root group which will contain all other elements/group
var root = myCanvas.createGroup();
# path is relative to $FG_ROOT (base package)
var path = "Fonts/Helvetica.png";
# create an image child for the texture
var child = root.createChild("image")
.setFile(path)
.setTranslation(100, 10)
.setSize(130, 130);