Fixed issue #532. Unexpected error occurs when zoom out image.

--HG--
branch : feature
This commit is contained in:
Valentina Zhuravska 2016-08-10 03:40:19 +03:00
parent 08c80f6a3d
commit e985ce26ad

View File

@ -39,6 +39,9 @@
#include <QMouseEvent> #include <QMouseEvent>
#include <qmath.h> #include <qmath.h>
const qreal maxScale = 50.0; // for zoom in
const qreal minScale = 0.004; // for zoom out
//--------------------------------------------------------------------------------------------------------------------- //---------------------------------------------------------------------------------------------------------------------
GraphicsViewZoom::GraphicsViewZoom(QGraphicsView* view) GraphicsViewZoom::GraphicsViewZoom(QGraphicsView* view)
: QObject(view), _view(view), _modifiers(Qt::ControlModifier), _zoom_factor_base(1.0015), : QObject(view), _view(view), _modifiers(Qt::ControlModifier), _zoom_factor_base(1.0015),
@ -55,12 +58,18 @@ GraphicsViewZoom::GraphicsViewZoom(QGraphicsView* view)
//--------------------------------------------------------------------------------------------------------------------- //---------------------------------------------------------------------------------------------------------------------
void GraphicsViewZoom::gentle_zoom(double factor) void GraphicsViewZoom::gentle_zoom(double factor)
{ {
// We need to check current scale factor because in Windows we have an error when we zoom in or zoom out to much.
// See issue #532: Unexpected error occurs when zoom out image.
// factor > 1 for zoomIn and factor < 1 for zoomOut.
if ((_view->transform().m11() < maxScale && factor > 1) ||
(_view->transform().m11() > minScale && factor < 1))
{
_view->scale(factor, factor); _view->scale(factor, factor);
if (factor < 1) if (factor < 1)
{ {
// Because QGraphicsView centers the picture when it's smaller than the view. And QGraphicsView's scrolls // Because QGraphicsView centers the picture when it's smaller than the view. And QGraphicsView's scrolls
// boundaries don't allow to put any picture point at any viewport position we will provide fictive scene size. // boundaries don't allow to put any picture point at any viewport position we will provide fictive scene
// Temporary and bigger than view, scene size will help position an image under cursor. // size. Temporary and bigger than view, scene size will help position an image under cursor.
FictiveSceneRect(_view->scene(), _view); FictiveSceneRect(_view->scene(), _view);
} }
_view->centerOn(target_scene_pos); _view->centerOn(target_scene_pos);
@ -71,6 +80,7 @@ void GraphicsViewZoom::gentle_zoom(double factor)
// In the end we just set correct scene size // In the end we just set correct scene size
VMainGraphicsView::NewSceneRect(_view->scene(), _view); VMainGraphicsView::NewSceneRect(_view->scene(), _view);
emit zoomed(); emit zoomed();
}
} }
//--------------------------------------------------------------------------------------------------------------------- //---------------------------------------------------------------------------------------------------------------------
@ -237,17 +247,27 @@ VMainGraphicsView::VMainGraphicsView(QWidget *parent)
//--------------------------------------------------------------------------------------------------------------------- //---------------------------------------------------------------------------------------------------------------------
void VMainGraphicsView::ZoomIn() void VMainGraphicsView::ZoomIn()
{ {
// We need to check current scale factor because in Windows we have an error when we zoom in or zoom out to much.
// See issue #532: Unexpected error occurs when zoom out image.
if (this->transform().m11() < maxScale)
{
scale(1.1, 1.1); scale(1.1, 1.1);
VMainGraphicsView::NewSceneRect(this->scene(), this); VMainGraphicsView::NewSceneRect(this->scene(), this);
emit NewFactor(1.1); emit NewFactor(1.1);
}
} }
//--------------------------------------------------------------------------------------------------------------------- //---------------------------------------------------------------------------------------------------------------------
void VMainGraphicsView::ZoomOut() void VMainGraphicsView::ZoomOut()
{ {
// We need to check current scale factor because in Windows we have an error when we zoom in or zoom out to much.
// See issue #532: Unexpected error occurs when zoom out image.
if (this->transform().m11() > minScale)
{
scale(1.0/1.1, 1.0/1.1); scale(1.0/1.1, 1.0/1.1);
VMainGraphicsView::NewSceneRect(this->scene(), this); VMainGraphicsView::NewSceneRect(this->scene(), this);
emit NewFactor(1.0/1.1); emit NewFactor(1.0/1.1);
}
} }
//--------------------------------------------------------------------------------------------------------------------- //---------------------------------------------------------------------------------------------------------------------