godotengine
/
godot
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Merge pull request #93149 from Malcolmnixon/smoothstep-degenerate-case 

Handle the smoothstep degenerate case of empty range
This commit is contained in:
Rémi Verschelde 2024-08-16 10:33:58 +02:00
parent 12eb1436f4 23fc704cbc
commit 27f3dd8d01
No known key found for this signature in database
GPG Key ID: C3336907360768E1
2 changed files with 14 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
core/math/math_funcs.h
View File

@ -447,14 +447,22 @@ public:
static _ALWAYS_INLINE_ double smoothstep(double p_from, double p_to, double p_s) {
if (is_equal_approx(p_from, p_to)) {
return p_from;
if (likely(p_from <= p_to)) {
return p_s <= p_from ? 0.0 : 1.0;
} else {
return p_s <= p_to ? 1.0 : 0.0;
}
}
double s = CLAMP((p_s - p_from) / (p_to - p_from), 0.0, 1.0);
return s * s * (3.0 - 2.0 * s);
}
static _ALWAYS_INLINE_ float smoothstep(float p_from, float p_to, float p_s) {
if (is_equal_approx(p_from, p_to)) {
return p_from;
if (likely(p_from <= p_to)) {
return p_s <= p_from ? 0.0f : 1.0f;
} else {
return p_s <= p_to ? 1.0f : 0.0f;
}
}
float s = CLAMP((p_s - p_from) / (p_to - p_from), 0.0f, 1.0f);
return s * s * (3.0f - 2.0f * s);

6
doc/classes/@GlobalScope.xml
View File

@ -1248,8 +1248,9 @@
<param index="1" name="to" type="float" />
<param index="2" name="x" type="float" />
<description>
Returns the result of smoothly interpolating the value of [param x] between [code]0[/code] and [code]1[/code], based on the where [param x] lies with respect to the edges [param from] and [param to].
The return value is [code]0[/code] if [code]x &lt;= from[/code], and [code]1[/code] if [code]x &gt;= to[/code]. If [param x] lies between [param from] and [param to], the returned value follows an S-shaped curve that maps [param x] between [code]0[/code] and [code]1[/code].
Returns a smooth cubic Hermite interpolation between [code]0[/code] and [code]1[/code].
For positive ranges (when [code]from &lt;= to[/code]) the return value is [code]0[/code] when [code]x &lt;= from[/code], and [code]1[/code] when [code]x &gt;= to[/code]. If [param x] lies between [param from] and [param to], the return value follows an S-shaped curve that smoothly transitions from [code]0[/code] to [code]1[/code].
For negative ranges (when [code]from &gt; to[/code]) the function is mirrored and returns [code]1[/code] when [code]x &lt;= to[/code] and [code]0[/code] when [code]x &gt;= from[/code].
This S-shaped curve is the cubic Hermite interpolator, given by [code]f(y) = 3*y^2 - 2*y^3[/code] where [code]y = (x-from) / (to-from)[/code].
[codeblock]
smoothstep(0, 2, -5.0) # Returns 0.0
@ -1259,6 +1260,7 @@
[/codeblock]
Compared to [method ease] with a curve value of [code]-1.6521[/code], [method smoothstep] returns the smoothest possible curve with no sudden changes in the derivative. If you need to perform more advanced transitions, use [Tween] or [AnimationPlayer].
[url=https://raw.githubusercontent.com/godotengine/godot-docs/master/img/smoothstep_ease_comparison.png]Comparison between smoothstep() and ease(x, -1.6521) return values[/url]
[url=https://raw.githubusercontent.com/godotengine/godot-docs/master/img/smoothstep_range.webp]Smoothstep() return values with positive, zero, and negative ranges[/url]
</description>
</method>
<method name="snapped">