Opened 15 years ago
Closed 15 years ago
#1974 closed patch (fixed)
Enable render caching where possible
| Reported by: | timlinux | Owned by: | timlinux |
|---|---|---|---|
| Priority: | minor: annoyance | Milestone: | Version 1.4.0 |
| Component: | MapCanvas | Version: | Trunk |
| Keywords: | cache performance | Cc: | |
| Must Fix for Release: | No | Platform: | All |
| Platform Version: | Awaiting user input: | no |
Description
User story 1:
Joe is reordering layers, each of which points back to a postgis database with thousands of records. Each time he drops a layer to a new position, he waits a long time while each layer redraws, even though the content of the layers is the same, just being rendered in a different order.
User story 2:
Jane is changing symbology in a layer. When she clicks apply, she waits a long time while all other layers redraw too.
User story 3:
Pete is hiding and showing layers. Each time he hides or shows a layer, he waits a long time while the layers redraw.
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The solution to this is to provide some kind of caching mechanism. The attached patch is my first draft that addresses the above scenarios and makes QGIS much more responsive when engaged in the activities described.
Please note the patch is a work in progress and there are some edge cases where it does not yet behave well. In order to activate caching, tick the checkbox for this in the rendering tab of the options panel (its disabled by default).
Attachments (6)
Change History (10)
by , 15 years ago
| Attachment: | qgis_render_cache_v3.diff added |
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by , 15 years ago
| Attachment: | qgis_rendercachepatch_v4_21Oct2009.diff.gz added |
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Updated patch which fixes some rendering issues
comment:1 by , 15 years ago
Version 5 offers dramatically better performance now that I have changed it to use QImage rather than QPixmap. The last remaining task is to clear the cache images of non-visible layers when the extents change to prevent rendering anomalies when enabling display of a layer after a zoom operation.
comment:2 by , 15 years ago
| Status: | new → assigned |
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by , 15 years ago
| Attachment: | qgis_rendercachepatch_v6_23Oct2009.diff added |
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Fixes for some cases where caching resulted in unexpected renders
comment:3 by , 15 years ago
Version 6 of the patch is now quite usable and deals well with most issues I think. I will propose this patch for inclusion into trunk.
by , 15 years ago
| Attachment: | qgis_rendercachepatch_v7_23Oct2009.diff added |
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Added missing sip / python bindings
by , 15 years ago
| Attachment: | qgis_rendercachepatch_v824Oct2009.diff added |
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Fixes refresh isssues with raster layer when symbology changed
comment:4 by , 15 years ago
| Resolution: | → fixed |
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| Status: | assigned → closed |
This patch is applied to trunk as of r11831.
Version 3 of my caching implementation