improve palette editor ui

- remove redundant RGB label
- in color picker, instruct user to press SPACE
- add toggle between 15 and 24 bit depth displaying

forms/colorpicker.ui

@@ -6,13 +6,22 @@
    <rect>
     <x>0</x>
     <y>0</y>
-    <width>357</width>
+    <width>383</width>
-    <height>186</height>
+    <height>243</height>
    </rect>
   </property>
   <property name="windowTitle">
    <string>Color Picker</string>
   </property>
+  <layout class="QVBoxLayout" name="verticalLayout_3">
+   <item>
+    <widget class="QFrame" name="frame_2">
+     <property name="frameShape">
+      <enum>QFrame::Box</enum>
+     </property>
+     <property name="frameShadow">
+      <enum>QFrame::Plain</enum>
+     </property>
      <layout class="QHBoxLayout" name="horizontalLayout">
       <item>
        <widget class="QFrame" name="frame_4">
@@ -187,6 +196,24 @@
       </item>
      </layout>
     </widget>
+   </item>
+   <item>
+    <widget class="QLabel" name="label_SPACE">
+     <property name="font">
+      <font>
+       <family>Courier</family>
+      </font>
+     </property>
+     <property name="text">
+      <string>press [SPACE] to capture color</string>
+     </property>
+     <property name="alignment">
+      <set>Qt::AlignCenter</set>
+     </property>
+    </widget>
+   </item>
+  </layout>
+ </widget>
  <resources/>
  <connections/>
 </ui>

include/ui/paletteeditor.h

@@ -36,7 +36,6 @@ private:
     QList<QList<QSlider*>> sliders;
     QList<QList<QSpinBox *>> spinners;
     QList<QFrame*> frames;
-    QList<QLabel*> rgbLabels;
     QList<QToolButton *> pickButtons;
     QList<QLineEdit *> hexEdits;
 
@@ -59,6 +58,9 @@ private:
     void setRgbFromHexEdit(int colorIndex);
     void setRgbFromSpinners(int colorIndex);
 
+    void setBitDepth(int bits);
+    int bitDepth = 24;
+
     class HexCodeValidator : public QValidator {
         virtual QValidator::State validate(QString &input, int &) const override {
             input = input.toUpper();

src/ui/paletteeditor.cpp

@@ -10,6 +10,10 @@
 #include <QMessageBox>
 
 static inline int rgb5(int rgb) { return round(static_cast<double>(rgb * 31) / 255.0); }
+static inline int rgb8(int rgb) { return round(rgb * 255. / 31.); }
+static inline int gbaRed(int rgb) { return rgb & 0x1f; }
+static inline int gbaGreen(int rgb) { return (rgb >> 5) & 0x1f; }
+static inline int gbaBlue(int rgb) { return (rgb >> 10) & 0x1f; }
 
 PaletteEditor::PaletteEditor(Project *project, Tileset *primaryTileset, Tileset *secondaryTileset, int paletteId, QWidget *parent) :
     QMainWindow(parent),
@@ -51,13 +55,7 @@ PaletteEditor::PaletteEditor(Project *project, Tileset *primaryTileset, Tileset
     this->frames.clear();
     for (int i = 0; i < 16; i++) {
         this->frames.append(this->ui->container->findChild<QFrame *>("colorFrame_" + QString::number(i)));
-        this->frames[i]->setFrameStyle(QFrame::Box | QFrame::Plain);
+        this->frames[i]->setFrameStyle(QFrame::NoFrame);
-    }
-
-    this->rgbLabels.clear();
-    for (int i = 0; i < 16; i++) {
-        this->rgbLabels.append(this->ui->container->findChild<QLabel *>("rgb_" + QString::number(i)));
-        this->rgbLabels[i]->setStyleSheet("QLabel { font-family: \"Courier\" }");
     }
 
     this->pickButtons.clear();
@@ -70,8 +68,6 @@ PaletteEditor::PaletteEditor(Project *project, Tileset *primaryTileset, Tileset
     for (int i = 0; i < 16; i++) {
         this->hexEdits.append(this->ui->container->findChild<QLineEdit *>("hex_" + QString::number(i)));
         this->hexEdits[i]->setValidator(hexValidator);
-        this->hexEdits[i]->setInputMask("HHHHHH");
-        this->hexEdits[i]->setMaxLength(6);
     }
 
     // Connect to function that will update color when hex edit is changed
@@ -91,6 +87,12 @@ PaletteEditor::PaletteEditor(Project *project, Tileset *primaryTileset, Tileset
         connect(this->pickButtons[i], &QToolButton::clicked, [this, i](){ this->pickColor(i); });
     }
 
+    setBitDepth(24);
+
+    // Connect bit depth buttons
+    connect(this->ui->bit_depth_15, &QRadioButton::toggled, [this](bool checked){ if (checked) this->setBitDepth(15); });
+    connect(this->ui->bit_depth_24, &QRadioButton::toggled, [this](bool checked){ if (checked) this->setBitDepth(24); });
+
     this->setPaletteId(paletteId);
     this->commitEditHistory(this->ui->spinBox_PaletteId->value());
     this->restoreWindowState();
@@ -109,11 +111,26 @@ void PaletteEditor::updateColorUi(int colorIndex, QRgb rgb) {
     int green = qGreen(rgb);
     int blue = qBlue(rgb);
 
+    if (this->bitDepth == 15) {
         // sliders
         this->sliders[colorIndex][0]->setValue(rgb5(red));
         this->sliders[colorIndex][1]->setValue(rgb5(green));
         this->sliders[colorIndex][2]->setValue(rgb5(blue));
 
+        // hex
+        int hex15 = (rgb5(blue) << 10) | (rgb5(green) << 5) | rgb5(red);
+        QString hexcode = QString::number(hex15, 16).toUpper();
+
+        // spinners
+        this->spinners[colorIndex][0]->setValue(rgb5(red));
+        this->spinners[colorIndex][1]->setValue(rgb5(green));
+        this->spinners[colorIndex][2]->setValue(rgb5(blue));
+    } else {
+        // sliders
+        this->sliders[colorIndex][0]->setValue(red);
+        this->sliders[colorIndex][1]->setValue(green);
+        this->sliders[colorIndex][2]->setValue(blue);
+
         // hex
         QColor color(red, green, blue);
         QString hexcode = color.name().remove(0, 1).toUpper();
@@ -123,17 +140,12 @@ void PaletteEditor::updateColorUi(int colorIndex, QRgb rgb) {
         this->spinners[colorIndex][0]->setValue(red);
         this->spinners[colorIndex][1]->setValue(green);
         this->spinners[colorIndex][2]->setValue(blue);
+    }
 
     // frame
     QString stylesheet = QString("background-color: rgb(%1, %2, %3);").arg(red).arg(green).arg(blue);
     this->frames[colorIndex]->setStyleSheet(stylesheet);
 
-    // rgb label
-    int w = 3;
-    QChar spc = ' ';
-    int base = 10;
-    this->rgbLabels[colorIndex]->setText(QString("  RGB(%1, %2, %3)").arg(red, w, base, spc).arg(green, w, base, spc).arg(blue, w, base, spc));
-
     setSignalsEnabled(true);
 }
 
@@ -156,6 +168,68 @@ void PaletteEditor::setSignalsEnabled(bool enabled) {
     }
 }
 
+void PaletteEditor::setBitDepth(int bits) {
+    setSignalsEnabled(false);
+    switch (bits) {
+    case 15:
+        for (int i = 0; i < 16; i++) {
+            // sliders ranged [0, 31] with 1 single step and 4 page step
+            this->sliders[i][0]->setSingleStep(1);
+            this->sliders[i][1]->setSingleStep(1);
+            this->sliders[i][2]->setSingleStep(1);
+            this->sliders[i][0]->setPageStep(4);
+            this->sliders[i][1]->setPageStep(4);
+            this->sliders[i][2]->setPageStep(4);
+            this->sliders[i][0]->setMaximum(31);
+            this->sliders[i][1]->setMaximum(31);
+            this->sliders[i][2]->setMaximum(31);
+
+            // spinners limited [0, 31] with 1 step
+            this->spinners[i][0]->setSingleStep(1);
+            this->spinners[i][1]->setSingleStep(1);
+            this->spinners[i][2]->setSingleStep(1);
+            this->spinners[i][0]->setMaximum(31);
+            this->spinners[i][1]->setMaximum(31);
+            this->spinners[i][2]->setMaximum(31);
+
+            // hex box now 4 digits
+            this->hexEdits[i]->setInputMask("HHHH");
+            this->hexEdits[i]->setMaxLength(4);
+        }
+        break;
+    case 24:
+    default:
+        for (int i = 0; i < 16; i++) {
+            // sliders ranged [0, 31] with 1 single step and 4 page step
+            this->sliders[i][0]->setSingleStep(8);
+            this->sliders[i][1]->setSingleStep(8);
+            this->sliders[i][2]->setSingleStep(8);
+            this->sliders[i][0]->setPageStep(24);
+            this->sliders[i][1]->setPageStep(24);
+            this->sliders[i][2]->setPageStep(24);
+            this->sliders[i][0]->setMaximum(255);
+            this->sliders[i][1]->setMaximum(255);
+            this->sliders[i][2]->setMaximum(255);
+
+            // spinners limited [0, 31] with 1 step
+            this->spinners[i][0]->setSingleStep(8);
+            this->spinners[i][1]->setSingleStep(8);
+            this->spinners[i][2]->setSingleStep(8);
+            this->spinners[i][0]->setMaximum(255);
+            this->spinners[i][1]->setMaximum(255);
+            this->spinners[i][2]->setMaximum(255);
+
+            // hex box now 4 digits
+            this->hexEdits[i]->setInputMask("HHHHHH");
+            this->hexEdits[i]->setMaxLength(6);
+        }
+        break;
+    }
+    this->bitDepth = bits;
+    refreshColorUis();
+    setSignalsEnabled(true);
+}
+
 void PaletteEditor::setRgb(int colorIndex, QRgb rgb) {
     int paletteNum = this->ui->spinBox_PaletteId->value();
 
@@ -172,24 +246,46 @@ void PaletteEditor::setRgb(int colorIndex, QRgb rgb) {
 }
 
 void PaletteEditor::setRgbFromSliders(int colorIndex) {
-    setRgb(colorIndex, qRgb(round(this->sliders[colorIndex][0]->value() * 255. / 31.),
+    if (this->bitDepth == 15) {
-                            round(this->sliders[colorIndex][1]->value() * 255. / 31.),
+        setRgb(colorIndex, qRgb(rgb8(this->sliders[colorIndex][0]->value()),
-                            round(this->sliders[colorIndex][2]->value() * 255. / 31.)));
+                                rgb8(this->sliders[colorIndex][1]->value()),
+                                rgb8(this->sliders[colorIndex][2]->value())));
+    } else {
+        setRgb(colorIndex, qRgb(this->sliders[colorIndex][0]->value(),
+                                this->sliders[colorIndex][1]->value(),
+                                this->sliders[colorIndex][2]->value()));
+    }
 }
 
 void PaletteEditor::setRgbFromHexEdit(int colorIndex) {
     QString text = this->hexEdits[colorIndex]->text();
     bool ok = false;
+    if (this->bitDepth == 15) {
+        int rgb15 = text.toInt(&ok, 16);
+        int rc = gbaRed(rgb15);
+        int gc = gbaGreen(rgb15);
+        int bc = gbaBlue(rgb15);
+        QRgb rgb = qRgb(rc, gc, bc);
+        if (!ok) rgb = 0xFFFFFFFF;
+        setRgb(colorIndex, rgb);
+    } else {
         QRgb rgb = text.toInt(&ok, 16);
         if (!ok) rgb = 0xFFFFFFFF;
         setRgb(colorIndex, rgb);
     }
+}
 
 void PaletteEditor::setRgbFromSpinners(int colorIndex) {
+    if (this->bitDepth == 15) {
+        setRgb(colorIndex, qRgb(rgb8(this->spinners[colorIndex][0]->value()),
+                                rgb8(this->spinners[colorIndex][1]->value()),
+                                rgb8(this->spinners[colorIndex][2]->value())));
+    } else {
         setRgb(colorIndex, qRgb(this->spinners[colorIndex][0]->value(),
                                 this->spinners[colorIndex][1]->value(),
                                 this->spinners[colorIndex][2]->value()));
     }
+}
 
 void PaletteEditor::refreshColorUis() {
     int paletteNum = this->ui->spinBox_PaletteId->value();