Make min/max level of VUMeter and LRAMeter adjustable.

diff --git a/lrameter.cpp b/lrameter.cpp
index f4395bec39ceb1094e4a472d67a110e4a05c4515..7b0f69189640096e477f1ead62cb783375cd8042 100644 (file)
--- a/lrameter.cpp
+++ b/lrameter.cpp
@@ -16,17 +16,7 @@ LRAMeter::LRAMeter(QWidget *parent)
 
 void LRAMeter::resizeEvent(QResizeEvent *event)
 {
-       const int margin = 5;
-
-       on_pixmap = QPixmap(width(), height());
-       QPainter on_painter(&on_pixmap);
-       on_painter.fillRect(0, 0, width(), height(), parentWidget()->palette().window());
-       draw_vu_meter(on_painter, width(), height(), margin, true);
-
-       off_pixmap = QPixmap(width(), height());
-       QPainter off_painter(&off_pixmap);
-       off_painter.fillRect(0, 0, width(), height(), parentWidget()->palette().window());
-       draw_vu_meter(off_painter, width(), height(), margin, false);
+       recalculate_pixmaps();
 }
 
 void LRAMeter::paintEvent(QPaintEvent *event)
@@ -101,3 +91,18 @@ void LRAMeter::paintEvent(QPaintEvent *event)
                painter.drawRect(2, y, width() - 5, 1);
        }
 }
+
+void LRAMeter::recalculate_pixmaps()
+{
+       const int margin = 5;
+
+       on_pixmap = QPixmap(width(), height());
+       QPainter on_painter(&on_pixmap);
+       on_painter.fillRect(0, 0, width(), height(), parentWidget()->palette().window());
+       draw_vu_meter(on_painter, width(), height(), margin, true, min_level, max_level);
+
+       off_pixmap = QPixmap(width(), height());
+       QPainter off_painter(&off_pixmap);
+       off_painter.fillRect(0, 0, width(), height(), parentWidget()->palette().window());
+       draw_vu_meter(off_painter, width(), height(), margin, false, min_level, max_level);
+}

diff --git a/lrameter.h b/lrameter.h
index 03d872fdc447b27dd402406190388334fc570dc3..e2e63ad813cb418b0143783ce33ddc2b1287f748 100644 (file)
--- a/lrameter.h
+++ b/lrameter.h
@@ -7,6 +7,8 @@
 #include <QWidget>
 #include <mutex>
 
+#include "vu_common.h"
+
 class LRAMeter : public QWidget
 {
        Q_OBJECT
@@ -22,14 +24,33 @@ public:
                QMetaObject::invokeMethod(this, "update", Qt::AutoConnection);
        }
 
+       double lufs_to_pos(float level_lu, int height)
+       {
+               return ::lufs_to_pos(level_lu, height, min_level, max_level);
+       }
+
+       void set_min_level(float min_level)
+       {
+               this->min_level = min_level;
+               recalculate_pixmaps();
+       }
+
+       void set_max_level(float max_level)
+       {
+               this->max_level = max_level;
+               recalculate_pixmaps();
+       }
+
 private:
        void resizeEvent(QResizeEvent *event) override;
        void paintEvent(QPaintEvent *event) override;
+       void recalculate_pixmaps();
 
        std::mutex level_mutex;
        float level_lufs = -HUGE_VAL;
        float range_low_lufs = -HUGE_VAL;
        float range_high_lufs = -HUGE_VAL;
+       float min_level = -18.0f, max_level = 9.0f;
 
        QPixmap on_pixmap, off_pixmap;
 };

diff --git a/vu_common.cpp b/vu_common.cpp
index f1a0619b642045d63d20f5eeac610b69f6f1fb16..38aba4c736d02945c95db5c34af7d83b46d2e8ab 100644 (file)
--- a/vu_common.cpp
+++ b/vu_common.cpp
@@ -9,23 +9,22 @@
 
 using namespace std;
 
-double lufs_to_pos(float level_lu, int height)
-{       
-       const float min_level = 9.0f;    // y=0 is top of screen, so “min” is the loudest level.
-       const float max_level = -18.0f;
+double lufs_to_pos(float level_lu, int height, float min_level, float max_level)
+{
+       // Note: “max” is the loudest level, but y=0 is top of screen.
 
        // Handle -inf.
-       if (level_lu < max_level) {
+       if (level_lu < min_level) {
                return height - 1;
        }
 
-       double y = height * (level_lu - min_level) / (max_level - min_level);
+       double y = height * (level_lu - max_level) / (min_level - max_level);
        y = max<double>(y, 0);
        y = min<double>(y, height - 1);
 
        // If we are big enough, snap to pixel grid instead of antialiasing
        // the edges; the unevenness will be less noticeable than the blurriness.
-       double height_per_level = height / (min_level - max_level) - 2.0;
+       double height_per_level = height / (max_level - min_level) - 2.0;
        if (height_per_level >= 10.0) {
                y = round(y);
        }
@@ -33,16 +32,16 @@ double lufs_to_pos(float level_lu, int height)
        return y;
 }
 
-void draw_vu_meter(QPainter &painter, int width, int height, int margin, bool is_on)
+void draw_vu_meter(QPainter &painter, int width, int height, int margin, bool is_on, float min_level, float max_level)
 {
        painter.fillRect(margin, 0, width - 2 * margin, height, Qt::black);
 
        for (int y = 0; y < height; ++y) {
                // Find coverage of “on” rectangles in this pixel row.
                double coverage = 0.0;
-               for (int level = -18; level < 9; ++level) {
-                       double min_y = lufs_to_pos(level + 1.0, height) + 1.0;
-                       double max_y = lufs_to_pos(level, height) - 1.0;
+               for (int level = floor(min_level); level <= ceil(max_level); ++level) {
+                       double min_y = lufs_to_pos(level + 1.0, height, min_level, max_level) + 1.0;
+                       double max_y = lufs_to_pos(level, height, min_level, max_level) - 1.0;
                        min_y = std::max<double>(min_y, y);
                        min_y = std::min<double>(min_y, y + 1);
                        max_y = std::max<double>(max_y, y);

diff --git a/vu_common.h b/vu_common.h
index 118eed89468ab3ae6b0fa77db6b404a7ebbb29ba..f065fcfb2b20302cfdb610223ce8c8580bb601c8 100644 (file)
--- a/vu_common.h
+++ b/vu_common.h
@@ -3,8 +3,8 @@
 
 #include <QPainter>
 
-double lufs_to_pos(float level_lu, int height);
+double lufs_to_pos(float level_lu, int height, float min_level, float max_level);
 
-void draw_vu_meter(QPainter &painter, int width, int height, int margin, bool is_on);
+void draw_vu_meter(QPainter &painter, int width, int height, int margin, bool is_on, float min_level, float max_level);
 
 #endif // !defined(_VU_COMMON_H)

diff --git a/vumeter.cpp b/vumeter.cpp
index 15240b4e5b9ac4ff552006d69b236e25b26ebcc6..c08e9dcd3f02ead70b39fd7165657b31c8fa1f63 100644 (file)
--- a/vumeter.cpp
+++ b/vumeter.cpp
@@ -12,13 +12,7 @@ VUMeter::VUMeter(QWidget *parent)
 
 void VUMeter::resizeEvent(QResizeEvent *event)
 {
-       on_pixmap = QPixmap(width(), height());
-       QPainter on_painter(&on_pixmap);
-       draw_vu_meter(on_painter, width(), height(), 0, true);
-
-       off_pixmap = QPixmap(width(), height());
-       QPainter off_painter(&off_pixmap);
-       draw_vu_meter(off_painter, width(), height(), 0, false);
+       recalculate_pixmaps();
 }
 
 void VUMeter::paintEvent(QPaintEvent *event)
@@ -39,3 +33,14 @@ void VUMeter::paintEvent(QPaintEvent *event)
        painter.drawPixmap(off_rect, off_pixmap, off_rect);
        painter.drawPixmap(on_rect, on_pixmap, on_rect);
 }
+
+void VUMeter::recalculate_pixmaps()
+{
+       on_pixmap = QPixmap(width(), height());
+       QPainter on_painter(&on_pixmap);
+       draw_vu_meter(on_painter, width(), height(), 0, true, min_level, max_level);
+
+       off_pixmap = QPixmap(width(), height());
+       QPainter off_painter(&off_pixmap);
+       draw_vu_meter(off_painter, width(), height(), 0, false, min_level, max_level);
+}

diff --git a/vumeter.h b/vumeter.h
index 7015091aa0f1d307f4aee97e5a58f60bfb5a6c79..33f8df149d339ce6cfe77b0fe89c0e53c2e469a8 100644 (file)
--- a/vumeter.h
+++ b/vumeter.h
@@ -7,6 +7,8 @@
 #include <QWidget>
 #include <mutex>
 
+#include "vu_common.h"
+
 class VUMeter : public QWidget
 {
        Q_OBJECT
@@ -20,12 +22,31 @@ public:
                QMetaObject::invokeMethod(this, "update", Qt::AutoConnection);
        }
 
+       double lufs_to_pos(float level_lu, int height)
+       {
+               return ::lufs_to_pos(level_lu, height, min_level, max_level);
+       }
+
+       void set_min_level(float min_level)
+       {
+               this->min_level = min_level;
+               recalculate_pixmaps();
+       }
+
+       void set_max_level(float max_level)
+       {
+               this->max_level = max_level;
+               recalculate_pixmaps();
+       }
+
 private:
        void resizeEvent(QResizeEvent *event) override;
        void paintEvent(QPaintEvent *event) override;
+       void recalculate_pixmaps();
 
        std::mutex level_mutex;
        float level_lufs = -HUGE_VAL;
+       float min_level = -18.0f, max_level = 9.0f;
 
        QPixmap on_pixmap, off_pixmap;
 };