添加OpenCv

PublicFunctions/BrushPad.cpp

@@ -0,0 +1,48 @@
+#include "BrushPad.h"
+#include <QPainter>
+#include <QPaintEvent>
+#include <QDebug>
+BrushPad::BrushPad(QWidget *parent)
+    : QGroupBox(parent)
+{
+    setMinimumSize(100, 100);
+    m_canvas = QPixmap(size());
+    m_canvas.fill(Qt::transparent);
+}
+
+void BrushPad::setBrushImage(const QImage &img)
+{
+    m_brush = img.convertToFormat(QImage::Format_ARGB32_Premultiplied);
+}
+
+void BrushPad::moveBrush(const QPoint &globalPos)
+{
+    // 1. 不管笔刷图，直接画一个 20×20 的红色方块到指定坐标
+    QPainter p(&m_canvas);
+    p.setCompositionMode(QPainter::CompositionMode_SourceOver);
+    p.drawImage(globalPos, m_brush);   // 直接叠加，不清屏
+    update();
+}
+
+
+void BrushPad::paintEvent(QPaintEvent *)
+{
+    // 让基类画边框/标题
+    QGroupBox::paintEvent(nullptr);
+
+    // 直接把我们自己的画布贴出来
+    QPainter p(this);
+
+
+    p.drawPixmap(contentsRect().topLeft(), m_canvas);
+    // 这里 **绝对不要再调用 update()/repaint()**
+}
+void BrushPad::resizeEvent(QResizeEvent *)
+{
+    // 画布跟随控件大小
+    QPixmap newPix(contentsRect().size());
+    newPix.fill(Qt::transparent);
+    QPainter p(&newPix);
+    p.drawPixmap(0, 0, m_canvas);
+    m_canvas = newPix;
+}