Assorted fixes

1 files changed, 10 insertions, 4 deletions

diff --git a/underwater/underwater.cpp b/underwater/underwater.cpp
index 3f9eb0f..fda9dcb 100644
--- a/underwater/underwater.cpp
+++ b/underwater/underwater.cpp
@@ -22,15 +22,20 @@
 ****************************************************************************/
 
 #include <QtGui>
+#include <cmath>
+
+#ifndef M_PI
+#define M_PI 3.1415926535897932384626433832795
+#endif
 
 void applyUnderwater(const QImage* img, QImage* result1, QImage *result2, int amp, qreal tick)
 {
     Q_ASSERT(img);
     Q_ASSERT(result1);
     Q_ASSERT(result2);
-    Q_ASSERT(img->size() != result1->size());
-    Q_ASSERT(img->size() != result2->size());
-    Q_ASSERT(img->format() != QImage::Format_ARGB32);
+    Q_ASSERT(img->size() == result1->size());
+    Q_ASSERT(img->size() == result2->size());
+    Q_ASSERT(img->format() == QImage::Format_ARGB32);
 
     int height = img->height();
     int width = img->width();
@@ -201,7 +206,8 @@ void UnderwaterDemo::paintEvent(QPaintEvent*)
 
         int amp = m_amplitudeSlider->value();
         qreal tick = m_timeLine->currentValue();
-        applyUnderwater(&m_image, &m_modifiedImage1, &m_modifiedImage2, amp, tick);
+        if (!m_image.isNull())
+            applyUnderwater(&m_image, &m_modifiedImage1, &m_modifiedImage2, amp, tick);
         painter.drawImage(0, 0, m_modifiedImage2);
     }
 }