QGIS API Documentation  3.23.0-Master (eb871beae0)
Public Member Functions | Static Public Member Functions | Protected Attributes | List of all members
QgsRenderChecker Class Reference

This is a helper class for unit tests that need to write an image and compare it to an expected result or render time. More...

#include <qgsrenderchecker.h>

Public Member Functions

 QgsRenderChecker ()
 Constructor for QgsRenderChecker. More...
 
bool compareImages (const QString &testName, const QString &referenceImageFile, const QString &renderedImageFile, unsigned int mismatchCount=0)
 Test using two arbitrary images at the specified paths for equality. More...
 
bool compareImages (const QString &testName, unsigned int mismatchCount=0, const QString &renderedImageFile=QString())
 Test using two arbitrary images (map renderer will not be used) More...
 
QString controlImagePath () const
 Returns the base path containing the reference images. More...
 
QVector< QgsDartMeasurementdartMeasurements () const
 Gets access to buffered dash messages. More...
 
int elapsedTime ()
 Returns the total elapsed time for the rendering test. More...
 
void enableDashBuffering (bool enable)
 Call this to enable internal buffering of dash messages. More...
 
QString expectedImageFile () const
 Returns the path to the expected image file. More...
 
QString imageToHash (const QString &imageFile)
 Gets an md5 hash that uniquely identifies an image. More...
 
bool isKnownAnomaly (const QString &diffImageFile)
 Gets a list of all the anomalies. More...
 
float matchPercent () const
 Returns the percent of pixels which matched the control image. More...
 
unsigned int matchTarget () const
 Returns the total number of pixels in the control image. More...
 
unsigned int mismatchCount () const
 Returns the number of pixels which did not match the control image. More...
 
QString renderedImage () const
 Returns the path of the rendered image generated by the test. More...
 
QString report ()
 Returns the HTML report describing the results of the test run. More...
 
bool runTest (const QString &testName, unsigned int mismatchCount=0)
 Test using renderer to generate the image to be compared. More...
 
void setColorTolerance (unsigned int colorTolerance)
 Set tolerance for color components used by runTest() and compareImages(). More...
 
void setControlExtension (const QString &extension)
 Sets file extension for the control image. More...
 
void setControlImagePath (const QString &path)
 Sets the base path containing the reference images. More...
 
void setControlName (const QString &name)
 Sets the base directory name for the control image (with control image path suffixed). More...
 
void setControlPathPrefix (const QString &name)
 Sets the path prefix where the control images are kept. More...
 
void setControlPathSuffix (const QString &name)
 
void setElapsedTimeTarget (int target)
 
void setMapSettings (const QgsMapSettings &mapSettings)
 
void setRenderedImage (const QString &imageFileName)
 Sets the file name of the rendered image generated by the test. More...
 
void setSizeTolerance (int xTolerance, int yTolerance)
 Sets the largest allowable difference in size between the rendered and the expected image. More...
 

Static Public Member Functions

static void drawBackground (QImage *image)
 Draws a checkboard pattern for image backgrounds, so that opacity is visible without requiring a transparent background for the image. More...
 

Protected Attributes

int mElapsedTime = 0
 
QString mExpectedImageFile
 
unsigned int mMatchTarget = 0
 
QString mRenderedImageFile
 
QString mReport
 

Detailed Description

This is a helper class for unit tests that need to write an image and compare it to an expected result or render time.

Definition at line 39 of file qgsrenderchecker.h.

Constructor & Destructor Documentation

◆ QgsRenderChecker()

QgsRenderChecker::QgsRenderChecker ( )

Constructor for QgsRenderChecker.

Definition at line 31 of file qgsrenderchecker.cpp.

Member Function Documentation

◆ compareImages() [1/2]

bool QgsRenderChecker::compareImages ( const QString &  testName,
const QString &  referenceImageFile,
const QString &  renderedImageFile,
unsigned int  mismatchCount = 0 
)

Test using two arbitrary images at the specified paths for equality.

Since
QGIS 3.18

Definition at line 258 of file qgsrenderchecker.cpp.

◆ compareImages() [2/2]

bool QgsRenderChecker::compareImages ( const QString &  testName,
unsigned int  mismatchCount = 0,
const QString &  renderedImageFile = QString() 
)

Test using two arbitrary images (map renderer will not be used)

Parameters
testName- to be used as the basis for writing a file to e.g. /tmp/theTestName.png
mismatchCount- defaults to 0 - the number of pixels that are allowed to be different from the control image. In some cases rendering may be non-deterministic. This parameter allows you to account for that by providing a tolerance.
renderedImageFileto optionally override the output filename
Note
: make sure to call setExpectedImage and setRenderedImage first.

Definition at line 241 of file qgsrenderchecker.cpp.

◆ controlImagePath()

QString QgsRenderChecker::controlImagePath ( ) const

Returns the base path containing the reference images.

This defaults to an internal QGIS test data path, but can be changed via setControlImagePath().

See also
setControlImagePath()

Definition at line 36 of file qgsrenderchecker.cpp.

◆ dartMeasurements()

QVector<QgsDartMeasurement> QgsRenderChecker::dartMeasurements ( ) const
inline

Gets access to buffered dash messages.

Only will return something if you call enableDashBuffering( true ); before.

Returns
buffered dash messages

Definition at line 225 of file qgsrenderchecker.h.

◆ drawBackground()

void QgsRenderChecker::drawBackground ( QImage *  image)
static

Draws a checkboard pattern for image backgrounds, so that opacity is visible without requiring a transparent background for the image.

Definition at line 78 of file qgsrenderchecker.cpp.

◆ elapsedTime()

int QgsRenderChecker::elapsedTime ( )
inline

Returns the total elapsed time for the rendering test.

Note
this only records time for actual render part.

Definition at line 94 of file qgsrenderchecker.h.

◆ enableDashBuffering()

void QgsRenderChecker::enableDashBuffering ( bool  enable)
inline

Call this to enable internal buffering of dash messages.

You may later call dashMessages() to get access to the buffered messages. If disabled (default) dash messages will be sent immediately.

Parameters
enableEnable or disable buffering

Definition at line 217 of file qgsrenderchecker.h.

◆ expectedImageFile()

QString QgsRenderChecker::expectedImageFile ( ) const
inline

Returns the path to the expected image file.

Returns
Path to the expected image file

Definition at line 208 of file qgsrenderchecker.h.

◆ imageToHash()

QString QgsRenderChecker::imageToHash ( const QString &  imageFile)

Gets an md5 hash that uniquely identifies an image.

Definition at line 60 of file qgsrenderchecker.cpp.

◆ isKnownAnomaly()

bool QgsRenderChecker::isKnownAnomaly ( const QString &  diffImageFile)

Gets a list of all the anomalies.

An anomaly is a rendered difference file where there is some red pixel content (indicating a render check mismatch), but where the output was still acceptable. If the render diff matches one of these anomalies we will still consider it to be acceptable.

Returns
a bool indicating if the diff matched one of the anomaly files

Definition at line 99 of file qgsrenderchecker.cpp.

◆ matchPercent()

float QgsRenderChecker::matchPercent ( ) const
inline

Returns the percent of pixels which matched the control image.

Definition at line 73 of file qgsrenderchecker.h.

◆ matchTarget()

unsigned int QgsRenderChecker::matchTarget ( ) const
inline

Returns the total number of pixels in the control image.

Definition at line 87 of file qgsrenderchecker.h.

◆ mismatchCount()

unsigned int QgsRenderChecker::mismatchCount ( ) const
inline

Returns the number of pixels which did not match the control image.

Definition at line 82 of file qgsrenderchecker.h.

◆ renderedImage()

QString QgsRenderChecker::renderedImage ( ) const
inline

Returns the path of the rendered image generated by the test.

This method will return either the path set with setRenderedImage() or generated in runTest().

Definition at line 133 of file qgsrenderchecker.h.

◆ report()

QString QgsRenderChecker::report ( )
inline

Returns the HTML report describing the results of the test run.

Definition at line 68 of file qgsrenderchecker.h.

◆ runTest()

bool QgsRenderChecker::runTest ( const QString &  testName,
unsigned int  mismatchCount = 0 
)

Test using renderer to generate the image to be compared.

Parameters
testName- to be used as the basis for writing a file to e.g. /tmp/theTestName.png
mismatchCount- defaults to 0 - the number of pixels that are allowed to be different from the control image. In some cases rendering may be non-deterministic. This parameter allows you to account for that by providing a tolerance.
Note
make sure to call setExpectedImage and setMapRenderer first

Definition at line 159 of file qgsrenderchecker.cpp.

◆ setColorTolerance()

void QgsRenderChecker::setColorTolerance ( unsigned int  colorTolerance)
inline

Set tolerance for color components used by runTest() and compareImages().

Default value is 0.

Parameters
colorToleranceis maximum difference for each color component including alpha to be considered correct.
Since
QGIS 2.1

Definition at line 145 of file qgsrenderchecker.h.

◆ setControlExtension()

void QgsRenderChecker::setControlExtension ( const QString &  extension)
inline

Sets file extension for the control image.

By default it is "png"

Since
QGIS 3.20

Definition at line 110 of file qgsrenderchecker.h.

◆ setControlImagePath()

void QgsRenderChecker::setControlImagePath ( const QString &  path)

Sets the base path containing the reference images.

See also
controlImagePath()
Since
QGIS 3.18

Definition at line 41 of file qgsrenderchecker.cpp.

◆ setControlName()

void QgsRenderChecker::setControlName ( const QString &  name)

Sets the base directory name for the control image (with control image path suffixed).

The path to the image will be constructed like this: controlImagePath() + '/' + control name + '/' + control name + '.' + extension ('png' by default)

Definition at line 46 of file qgsrenderchecker.cpp.

◆ setControlPathPrefix()

void QgsRenderChecker::setControlPathPrefix ( const QString &  name)
inline

Sets the path prefix where the control images are kept.

This will be appended to controlImagePath().

Definition at line 116 of file qgsrenderchecker.h.

◆ setControlPathSuffix()

void QgsRenderChecker::setControlPathSuffix ( const QString &  name)

Definition at line 52 of file qgsrenderchecker.cpp.

◆ setElapsedTimeTarget()

void QgsRenderChecker::setElapsedTimeTarget ( int  target)
inline

Definition at line 95 of file qgsrenderchecker.h.

◆ setMapSettings()

void QgsRenderChecker::setMapSettings ( const QgsMapSettings mapSettings)
Since
QGIS 2.4

Definition at line 73 of file qgsrenderchecker.cpp.

◆ setRenderedImage()

void QgsRenderChecker::setRenderedImage ( const QString &  imageFileName)
inline

Sets the file name of the rendered image generated by the test.

Definition at line 126 of file qgsrenderchecker.h.

◆ setSizeTolerance()

void QgsRenderChecker::setSizeTolerance ( int  xTolerance,
int  yTolerance 
)
inline

Sets the largest allowable difference in size between the rendered and the expected image.

Parameters
xTolerancex tolerance in pixels
yTolerancey tolerance in pixels
Since
QGIS 2.12

Definition at line 153 of file qgsrenderchecker.h.

Member Data Documentation

◆ mElapsedTime

int QgsRenderChecker::mElapsedTime = 0
protected

Definition at line 230 of file qgsrenderchecker.h.

◆ mExpectedImageFile

QString QgsRenderChecker::mExpectedImageFile
protected

Definition at line 232 of file qgsrenderchecker.h.

◆ mMatchTarget

unsigned int QgsRenderChecker::mMatchTarget = 0
protected

Definition at line 229 of file qgsrenderchecker.h.

◆ mRenderedImageFile

QString QgsRenderChecker::mRenderedImageFile
protected

Definition at line 231 of file qgsrenderchecker.h.

◆ mReport

QString QgsRenderChecker::mReport
protected

Definition at line 228 of file qgsrenderchecker.h.


The documentation for this class was generated from the following files: