The GtkGears widget is a bit too chatty, especially when used inside
demos like the fishbowl. Let's use g_debug() instead of g_print() for
the GL debugging message.
This adds a bunch of snazz to the gltransitions demo. It is perhaps
a bit overloaded now, but it demos everything that we can do.
Changes:
* The fire shader is now not a bin, it just renders an animating
background with no textures involved.
* The stacks don't all start on the same page.
* The shaderbin passes the mouse coordinate to the shader.
* The shaderbin allows specifying a "border" so that you can
cause effects outside the bin child (something that is new to gtk4).
* All the buttons and the stacks are now in shader-bins that runs
a wobbly-widget effect based on the mouse position that
wobbles outside the child allocation.
Add adds a demo showing off GskGLShaderNode in various ways.
It has a transistion widget, using some examples from
gl-transitions.com, with child widgets being both images, a GL area
and real widgets (that let you edit the transition shaders
themselves.
It also has a fancy fire effect on hove on the buttons.
Redo the tag insertion function to avoid quadratic
behavior, and at the same time, fix handling of
alpha for color attributes.
Update the copy of this function in gtk4-demo
as well.
Add the names of the main widgets as keywords to
our demos, but also things like "game". This helps
finding relevant demos in our growing list. You
can now for example type "label", and find the
"error states" and "links" demos showing GtkLabel
features.
Filter the sidebar on keywords that can be provided
by the demos. We extract keywords from the doc comment
at the top of each demo source by looking for words that
look like class names. We also allow to specify keywords
explicitly.
In the video player demo, we have a button to make
the window fullscreen, but no easy way back. Add
the usual F11 keybinding, to make things at least
somewhat recoverable.
This adds a small demo of using OpenGL shaders, it renders a quad
over the entire widget with a custom fragment shader. The coordinates
and the uniform names are compatible with the ones on shadertoy.com
(although some features, like texture inputs are missing currently).
The default shader in the demo is
https://www.shadertoy.com/view/wsjBD3 which is CC0, so it is
redistributable by Gtk+ (most other shaders are CC-BY-NC-SA which
isn't obviously compatible). I also added a set of buttons loading
a few other CC0 shaders I found.
