paweld/lazarus
1
0
Fork 0
mirror of https://gitlab.com/freepascal.org/lazarus/lazarus.git synced 2025-04-07 22:58:14 +02:00
Code Issues Packages Projects Releases Wiki Activity

Docs: LCL/graphics. Updates TRasterImage.RequestTransparentColor topic to clarify content.

Browse Source 
* Discussion: https://forum.lazarus.freepascal.org/index.php/topic,67483.msg519648

(cherry picked from commit 431a3980e1)
This commit is contained in:
dsiders 2024-12-30 03:32:49 +00:00
parent f582b606db
commit f3c47a1f6a
1 changed files with 19 additions and 10 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

29
docs/xml/lcl/graphics.xml
View File

@ -12216,21 +12216,31 @@ Gets the color used to represent transparent pixels in the image.
<descr>
<p>
<var>RequestTransparentColor</var> is a <var>TColor</var> function used to
get the color for transparent pixels in the image. It is called when the
value <var>tmFixed</var> is assigned to the <var>TransparentMode</var>
property.
resolve the color value for transparent pixels in the image. It is used to
translate the value clDefault in the TransparentColor property to an actual
color value.
</p>
<p>
RequestTransparentColor examines pixels in the raw image data to get the
return value for the method. It gets the color for the pixel located at the
bottom-left corner of the image (x = 0, y - Height-1).
When TransparentColor is set to clDefault, the return value for the method is
used as the color for transparent pixels. The return value is the pixel color
stored at the bottom-left corner of the image (x = 0, y = Height-1).
</p>
<p>
When <var>Empty</var> returns <b>True</b> (raw image data is not available),
the return value is <var>clNone</var>.
If TransparentColor contains a different TColor value, it is used in its
unmodified form.
</p>
<p>
When <var>Empty</var> returns <b>True</b>, raw image data is not available and
the return value is set to <var>clNone</var>.
</p>
<p>
RequestTransparentColor is also called when the value in TransparentMode is
changed to tmAuto. If TransparentMode is set to tmFixed, the TransparentColor
is used as specified.
</p>
</descr>
<seealso>
<link id="TRasterImage.TransparentColor"/>
<link id="TRasterImage.TransparentMode"/>
<link id="TGraphic.Empty"/>
<link id="TTransparentMode"/>
@ -13051,8 +13061,7 @@ platforms or widgetsets.
<p>
<var>TransparentColor</var> is a <var>TColor</var> property which indicates
the color used for transparent pixels in the raw image data. The default
value for the property is
<var>clDefault</var>.
value for the property is <var>clDefault</var>.
</p>
<p>
TransparentColor is used along with <var>TransparentMode</var> to determine