Why change header logo width and height?

I have successfully replaced the zen cart logo with my logo in the header by changing the following line in includes/languages/english/custom/header.php:

define('HEADER_LOGO_IMAGE', 'mylogo.jpg'

I wanted to modify the width and height of my logo by modifying the following two lines:

define('HEADER_LOGO_WIDTH', '192px');
define('HEADER_LOGO_HEIGHT', '64px');

I didn´t work. If I change the 192px and 64px to different numbers, it has no effect on how the image is displayed.

Am I doing something wrong? If not, what is the point of those two lines?

Also, how can I modify the displayed dimensions of the logo if I don´t want to change the actual logo file?

Thanks in advance for some help. :D

Are you trying to change the position of the logo?

Thank for the quick response.

No, I am not trying to change the position of the logo. For now I am leaving it left justified.

The problem is, if I change the following two lines in the file includes/languages/english/custom/header.php

define('HEADER_LOGO_WIDTH', '192px');
define('HEADER_LOGO_HEIGHT', '64px');

to something like

define('HEADER_LOGO_WIDTH', '10px');
define('HEADER_LOGO_HEIGHT', '5px');

it doesn´t seem to change the way the logo is displayed.

Therefore I don´t understand what those two lines do. I was hoping to be able to adjust the width and height of the logo by changing those two lines.

If I use the firebug addon in Firefox browser, I can scroll over the logo and find similar lines of code that, when changed, subsequently change the size of the logo that is displayed by the browser, independent of the actual size of the file.

Am I making any sense? :shocking:

it doesn´t seem to change the way the logo is displayed.

They won't, but they will affect the way other elements in the header are positioned in certain browsers.