Making a mock-up slanting images and logo's

Discuss the drawing application

Making a mock-up slanting images and logo's

Postby SvenAERTS228 » Sun Apr 14, 2019 4:35 pm

Hi,
I have to make a mock-up of a stand for a fair.
They give me a photo of previous stand they want me to update with new photos and logo's.
You know how a circular logo becomes slanted to an oval when it is sticked on a wall and you look at it from an angle?
I can create that effect using Format - Positioning - Slant; then a pop-up window allows to set the degrees etc. But can't we make that stay on top so I can experiment till I find the right slant angle ?
And then I need to distort it - is there a function for that? So the now oval logo follows the perspective lines when you look from the side to the wall.
As usual thy very much :)
Attachments
Open Office Slant Screen Shot 2019-04-14 at 16.29.44.jpg
Open Office Slant Screen Shot 2019-04-14 at 16.29.00.jpg
Open Office Slant
OpenOffice 3.3.0.
OS: Mac OSX
SvenAERTS228
 
Posts: 1
Joined: Fri Jan 06, 2012 6:04 pm

Re: Making a mock-up slanting images and logo's

Postby Lupp » Mon Apr 15, 2019 4:33 pm

Let sh be the variable for accessing the shape. You need to use the properties sh.Size (There is no property for the aspect ratio afaik.), sh.ShearAngle and sh.RotateAngle via dialog Position and Size which you can open from the context menu of the shape (UI). How this all is related is mathematics.

If you want to use custom code:
There is also the property sh.Transformation which is a 3x3 matrix (in a specific naming of/access to the elements) which describes the affine transformation that was applied to the underlying shape in homogenous coordinates. (See https://en.wikipedia.org/wiki/Homogeneous_coordinates e.g.) If you are familiar with homogenous coordinates and want to go this way, you need to use LibreOffice. There sh.RotateAngle and sh.ShearAngle are still supported though deprecated. An sh.Transformation matrix on the other hand can be assigned while this property is read-only in Apache OpenOffice.
On Windows 10: LibreOffice 6.2 and older versions, PortableOpenOffice 4.1.5 and older, StarOffice 5.2
---
Lupp from München
User avatar
Lupp
Volunteer
 
Posts: 2490
Joined: Sat May 31, 2014 7:05 pm
Location: München, Germany

Re: Making a mock-up slanting images and logo's

Postby keme » Tue Apr 16, 2019 10:17 am

You can do it "by hand"/visually if you convert your object to 3D first. See this rough video guide.
Click on selected object to toggle between resize and rotate handles.
When you convert an object from 2D to 3D, the side rotate handles change from "slant distortion" to perspective adjustment (perceived rotation around axes parallel to the plane defined by the screen. Corner handles still rotate around the axis normal to that plane.
Note that Draw's "3D" is just an emulation for visual purposes. You cannot handle true 3d objects, only 2D objects with some (in some cases extensive) 3D artifacts.

Please note
I haven't verified that this procedure works for all kinds of object, nor have I tested with older versions of the suite.
Also, object conversion in Draw sometimes does unexpected things to graphical components/properties. Pay attention to detail!

Most likely, you are better off using proper tools for graphics design.
Adobe Photoshop and the GIMP both have tools for perspective adjustment, and I believe Inkscape can do it reasonably well too.
User avatar
keme
Volunteer
 
Posts: 3159
Joined: Wed Nov 28, 2007 10:27 am
Location: Egersund, Norway


Return to Draw

Who is online

Users browsing this forum: Google [Bot] and 3 guests