Symbol exp var #61471

roya0045 · 2025-04-14T21:24:00Z

Description

Here is an updated version of the previously proposed changes, this new version includes a few needed changes that are detailed below.

QgsLayerTReeModelLegendNode

changes in QgsSymbolLegendNode::evaluateLabel

Minor change in evaluation
changes in QgsSymbolLegendNode::createSymbolScope

Added some safety, retreival of stored layer style in cases where the style if the layer in the map is not the same as in the app and must be retreived.

Added the "legend_item_expression" variable that returns a string that represent the rendering condition.

QgsSymbolLayerUtils

These changes were needed as overriding temporarily the symbology of the vector layer in order to retreive the symbol was more expensive than to simply parse the string stored.

Addition of QgsSymbolLayerUtils::getStyleNodeMinMax

Utility class to transform scale limitation into text, as done in QgsRuleBasedRenderer::legendKeyToExpression
Addition of QgsSymbolLayerUtils::ruleNodeExpression

Recursive function to collect all relevant rules to properly translate the rendering condition into a standalone expression, as done in QgsRuleBasedRenderer::legendKeyToExpression
Addition of QgsSymbolLayerUtils::legendKeyToExpression

Utility class that takes a style string and parse it to obtain an expression for the provided symbol key. Supports existing vector renderer as of writing this.

QgsExpressionFunction

changes in fcnAggregateGeneric

Currently the aggregate results are cached using attributes from the expression, the layer used and the feature evaluate. In the case of the layout the feature of the context can be the atlas feature, but when it comes to symbols, the current key do not help to evaluate the result using the elements present in the layout. Additionnaly in expressions some variable can be used ( map_extent, legend_item_expression, symbol_label). Those variable name will be used to create the cache, regardless if their content changed. The proposed changes evaluate all variable into a string to help distinguish between the results.

When using in a vector layer this is not a problem as the feature id will change, but in the case where the layer id will not change and the feature id ( being the atlas feature) will not change, which caused the first evaluated result to be the same for each symbol instead of evaluating it once per symbol.

This approach might seem heavy handed with expanding geometry as wkt, but this seemed to be the best way to avoid fetching the wrong cached results

Adds: - Expression variable to represent rendering rule of a symbol - Parsin of style string to retreive rendering rule of a symbol - Use evaluated expression variable in aggregate caching to avoid unwanted retreival

for more information, see https://pre-commit.ci

github-actions · 2025-04-14T22:38:57Z

🪟 Windows builds

Download Windows builds of this PR for testing.
Debug symbols for this build are available here.
(Built from commit e92d77c)

🪟 Windows Qt6 builds

Download Windows Qt6 builds of this PR for testing.
(Built from commit e92d77c)

github-actions · 2025-04-19T23:06:09Z

Tests failed for Qt 5

One or more tests failed using the build from commit 0645c1c

composer_legend_theme_expression_scope

Test failed at testLegendExpressionWithStyles at tests/src/python/test_qgslayoutlegend.py:1316

Rendered image did not match tests/testdata/control_images/composer_legend/expected_composer_legend_theme_expression_scope/expected_composer_legend_theme_expression_scope.png (found 2636 pixels different)

The full test report (included comparison of rendered vs expected images) can be found here.

Further documentation on the QGIS test infrastructure can be found in the Developer's Guide.

github-actions · 2025-04-20T16:12:36Z

Tests failed for Qt 6

One or more tests failed using the build from commit b99f766

composer_legend_theme_expression_scope

Test failed at testLegendExpressionWithStyles at tests/src/python/test_qgslayoutlegend.py:1316

Rendered image did not match tests/testdata/control_images/composer_legend/expected_composer_legend_theme_expression_scope/expected_composer_legend_theme_expression_scope.png (found 58383 pixels different)

The full test report (included comparison of rendered vs expected images) can be found here.

Further documentation on the QGIS test infrastructure can be found in the Developer's Guide.

for more information, see https://pre-commit.ci

roya0045 · 2025-04-21T00:24:43Z

Unsure why tests are erroring with "too msny arguments" on the new sip function.

for more information, see https://pre-commit.ci

github-actions · 2025-05-06T02:59:21Z