Improving QGIS source code efficiency?
I have noticed in the QGIS source code that the map layers gets added in two
different places, in the Canvas and in the registry as follow:
QgsMapLayerRegistry::instance()->addMapLayers(theMapLayers, TRUE);
//! Create the Map Canvas
m_pMapCanvas = new QgsMapCanvas(0, 0);
// Set the Map Canvas Layer Set
m_pMapCanvas->setLayerSet(myRList);
It seems like two separate copies of the map layers is being added to two different places, is there is away to make this more efficient?
qgis c++
add a comment |
I have noticed in the QGIS source code that the map layers gets added in two
different places, in the Canvas and in the registry as follow:
QgsMapLayerRegistry::instance()->addMapLayers(theMapLayers, TRUE);
//! Create the Map Canvas
m_pMapCanvas = new QgsMapCanvas(0, 0);
// Set the Map Canvas Layer Set
m_pMapCanvas->setLayerSet(myRList);
It seems like two separate copies of the map layers is being added to two different places, is there is away to make this more efficient?
qgis c++
add a comment |
I have noticed in the QGIS source code that the map layers gets added in two
different places, in the Canvas and in the registry as follow:
QgsMapLayerRegistry::instance()->addMapLayers(theMapLayers, TRUE);
//! Create the Map Canvas
m_pMapCanvas = new QgsMapCanvas(0, 0);
// Set the Map Canvas Layer Set
m_pMapCanvas->setLayerSet(myRList);
It seems like two separate copies of the map layers is being added to two different places, is there is away to make this more efficient?
qgis c++
I have noticed in the QGIS source code that the map layers gets added in two
different places, in the Canvas and in the registry as follow:
QgsMapLayerRegistry::instance()->addMapLayers(theMapLayers, TRUE);
//! Create the Map Canvas
m_pMapCanvas = new QgsMapCanvas(0, 0);
// Set the Map Canvas Layer Set
m_pMapCanvas->setLayerSet(myRList);
It seems like two separate copies of the map layers is being added to two different places, is there is away to make this more efficient?
qgis c++
qgis c++
edited Nov 11 at 16:37
Vince
14.4k32647
14.4k32647
asked Nov 11 at 5:39
user9995
473
473
add a comment |
add a comment |
1 Answer
1
active
oldest
votes
There's no inefficiency here. They are only c++ pointers to the same layer instance -- it's not two instances in separate memory of the same map layer.
add a comment |
Your Answer
StackExchange.ready(function()
var channelOptions =
tags: "".split(" "),
id: "79"
;
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function()
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled)
StackExchange.using("snippets", function()
createEditor();
);
else
createEditor();
);
function createEditor()
StackExchange.prepareEditor(
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: false,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: null,
bindNavPrevention: true,
postfix: "",
imageUploader:
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
,
onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
);
);
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function ()
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fgis.stackexchange.com%2fquestions%2f302168%2fimproving-qgis-source-code-efficiency%23new-answer', 'question_page');
);
Post as a guest
Required, but never shown
1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
There's no inefficiency here. They are only c++ pointers to the same layer instance -- it's not two instances in separate memory of the same map layer.
add a comment |
There's no inefficiency here. They are only c++ pointers to the same layer instance -- it's not two instances in separate memory of the same map layer.
add a comment |
There's no inefficiency here. They are only c++ pointers to the same layer instance -- it's not two instances in separate memory of the same map layer.
There's no inefficiency here. They are only c++ pointers to the same layer instance -- it's not two instances in separate memory of the same map layer.
answered Nov 11 at 8:56
ndawson
18k22640
18k22640
add a comment |
add a comment |
Thanks for contributing an answer to Geographic Information Systems Stack Exchange!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
To learn more, see our tips on writing great answers.
Some of your past answers have not been well-received, and you're in danger of being blocked from answering.
Please pay close attention to the following guidance:
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
To learn more, see our tips on writing great answers.
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function ()
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fgis.stackexchange.com%2fquestions%2f302168%2fimproving-qgis-source-code-efficiency%23new-answer', 'question_page');
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown