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<p>Hi Patrick,</p>
<p>This uses some memory (~ canvas width pixels * canvas height
pixels * 8 preview images * 32 bit RGBA), so let's assume 50 MB to
100 MB.</p>
<p>This consumption is independent from the number or type of
layers.</p>
<p>Matthias<br>
</p>
<br>
<div class="moz-cite-prefix">On 11/16/2017 08:02 AM, Patrick Dunford
wrote:<br>
</div>
<blockquote type="cite"
cite="mid:b03982ea-9ee2-afda-1028-1c7b15e4b259@gmail.com">
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<p>So to put it another way this is the reason why Qgis wants to
use a huge amount of memory (40 GB) when I have a lot of raster
images loaded in the background. <br>
</p>
<br>
<div class="moz-cite-prefix">On 16/11/17 18:56, Tim Sutton wrote:<br>
</div>
<blockquote type="cite"
cite="mid:240D3348-E0F6-43AC-8AAF-41371976ED71@kartoza.com">
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charset=utf-8">
Hi<br class="">
<div><br class="">
<blockquote type="cite" class="">
<div class="">On 16 Nov 2017, at 04:35, Patrick Dunford <<a
href="mailto:enzedrailmaps@gmail.com" class=""
moz-do-not-send="true">enzedrailmaps@gmail.com</a>>
wrote:</div>
<br class="Apple-interchange-newline">
<div class="">
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<div>Its application logic to prefetch / pre-render offscreen
content in anticipation of user panning the map.</div>
<div><br class="">
</div>
<div>Regards</div>
<div><br class="">
</div>
<div>Tim</div>
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