[clutter-docs] Update the animation tutorial

The Alpha API and usage has been changed by the recent overhaul
of the ClutterAlpha class; hence, we need to update the relative
documentation in the animation tutorial.
This commit is contained in:
Emmanuele Bassi 2009-01-28 16:44:22 +00:00
parent b09ee495a5
commit 0530405899

View File

@ -290,67 +290,14 @@ main (int argc, char *argv[])
</para> </para>
<para> <para>
A ClutterAlpha is simply a 'function of time' (not a pixel alpha!). It A ClutterAlpha is simply a 'function of time' (not a pixel alpha channel!).
is created by referencing a source timeline and a function which It is created by referencing a source timeline and an "easing mode" which
produces a value between 0 and %CLUTTER_ALPHA_MAX dependant on the produces a value between -1 and 2 depending on the progress of the
timeline position. Various prebuilt alpha functions are included timeline. Clutter provides various easing modes, as described by
with Clutter these include the #ClutterAnimationMode enumeration. It is also possible to register
a new animation mode using clutter_alpha_register_func() or to provide
a custom #ClutterAlphaFunc for a specific #ClutterAlpha instance.
</para>
<para>
<variablelist>
<varlistentry>
<term>%CLUTTER_ALPHA_RAMP_INC</term>
<listitem><simpara>Increasing ramp function</simpara></listitem>
</varlistentry>
<varlistentry>
<term>%CLUTTER_ALPHA_RAMP_DEC</term>
<listitem><simpara>Decreasing ramp function</simpara></listitem>
</varlistentry>
<varlistentry>
<term>%CLUTTER_ALPHA_RAMP</term>
<listitem><simpara>Full ramp function</simpara></listitem>
</varlistentry>
<varlistentry>
<term>%CLUTTER_ALPHA_SINE_INC</term>
<listitem><simpara>Increasing sine function</simpara></listitem>
</varlistentry>
<varlistentry>
<term>%CLUTTER_ALPHA_SINE_DEC</term>
<listitem><simpara>Decreasing sine function</simpara></listitem>
</varlistentry>
<varlistentry>
<term>%CLUTTER_ALPHA_SINE_HALF</term>
<listitem><simpara>Half sine function</simpara></listitem>
</varlistentry>
<varlistentry>
<term>%CLUTTER_ALPHA_SINE</term>
<listitem><simpara>Full sine function</simpara></listitem>
</varlistentry>
<varlistentry>
<term>%CLUTTER_ALPHA_SQUARE</term>
<listitem><simpara>Square waveform ("step") function</simpara></listitem>
</varlistentry>
<varlistentry>
<term>%CLUTTER_ALPHA_SMOOTHSTEP_INC</term>
<listitem><simpara>Increasing smooth transition step
function</simpara></listitem>
</varlistentry>
<varlistentry>
<term>%CLUTTER_ALPHA_SMOOTHSTEP_DEC</term>
<listitem><simpara>Decreasing smooth transition step
function</simpara></listitem>
</varlistentry>
<varlistentry>
<term>%CLUTTER_ALPHA_EXP_INC</term>
<listitem><simpara>Increasing exponential function</simpara></listitem>
</varlistentry>
<varlistentry>
<term>%CLUTTER_ALPHA_EXP_DEC</term>
<listitem><simpara>Decreasing exponential function</simpara></listitem>
</varlistentry>
</variablelist>
</para> </para>
<para> <para>
@ -369,10 +316,7 @@ main (int argc, char *argv[])
feature of the actor dependant on the Alpha's value. For example a feature of the actor dependant on the Alpha's value. For example a
path based behaviour applied to an actor will alter its position path based behaviour applied to an actor will alter its position
along the path dependant on the current alpha value over time. The along the path dependant on the current alpha value over time. The
actual motion will depend on the chosen #ClutterAlphaFunc - a actual motion will depend on the chosen "easing mode".
#CLUTTER_ALPHA_RAMP_INC making it to move at constant speed along the
path, a #CLUTTER_ALPHA_SINE making it alternate from one end of the
path to the other with non constant speed.
</para> </para>
<para> <para>
@ -393,9 +337,9 @@ main (int argc, char *argv[])
<blockquote> <blockquote>
The actors position between the path's end points directly correlates The actors position between the path's end points directly correlates
to the #ClutterAlpha's current alpha value driving the behaviour. With to the #ClutterAlpha's current alpha value driving the behaviour. With
the #ClutterAlpha's function set to %CLUTTER_ALPHA_RAMP_INC the actor the #ClutterAlpha's animation mode set to %CLUTTER_LINEAR the actor
will follow the path at a constant velocity, but when changing to will follow the path at a constant velocity, but when changing to
%CLUTTER_ALPHA_SINE_INC the actor initially accelerates before quickly %CLUTTER_EASE_SINE_IN_OUT the actor initially accelerates before quickly
decelerating. decelerating.
</blockquote> </blockquote>
</figure> </figure>
@ -468,9 +412,7 @@ main (int argc, char *argv[])
clutter_timeline_set_loop (timeline, TRUE); clutter_timeline_set_loop (timeline, TRUE);
/* Set an alpha func to power the behaviour */ /* Set an alpha func to power the behaviour */
alpha = clutter_alpha_new_full (timeline, alpha = clutter_alpha_new_full (timeline, CLUTTER_EASE_SINE_IN_OUT);
CLUTTER_ALPHA_SINE,
NULL, NULL);
behave = clutter_behaviour_ellipse_new (alpha, behave = clutter_behaviour_ellipse_new (alpha,
200, /* center x */ 200, /* center x */
@ -576,7 +518,7 @@ main (int argc, char *argv[])
ClutterButtonEvent *event, ClutterButtonEvent *event,
gpointer user_data) gpointer user_data)
{ {
clutter_actor_animate (actor, CLUTTER_SINE_IN_OUT, 500, clutter_actor_animate (actor, CLUTTER_EASE_SINE_OUT, 500,
"x", event-&gt;x, "x", event-&gt;x,
"y", event-&gt;y, "y", event-&gt;y,
NULL); NULL);