Initial XGA-2 implementation, (same as XGA-1 internally, but able to do 800x600 officially), selection is possible only on QT at the moment.

Refactored the ROP/MIX of the XGA accelerator.
Bus type variable added to make sure the device is an ISA-16 device or MCA in its dedicated register.

src/qt/qt_settingsdisplay.cpp

@@ -24,6 +24,7 @@ extern "C" {
 #include <86box/device.h>
 #include <86box/machine.h>
 #include <86box/video.h>
+#include <86box/vid_xga_device.h>
 }
 
 #include "qt_deviceconfig.hpp"
@@ -102,6 +103,14 @@ void SettingsDisplay::on_pushButtonConfigureVoodoo_clicked() {
     DeviceConfig::ConfigureDevice(&voodoo_device, 0, qobject_cast<Settings*>(Settings::settings));
 }
 
+void SettingsDisplay::on_pushButtonConfigureXga_clicked() {
+    if (machine_has_bus(machineId, MACHINE_BUS_MCA) > 0) {
+        DeviceConfig::ConfigureDevice(&xga_device, 0, qobject_cast<Settings*>(Settings::settings));
+    } else {
+        DeviceConfig::ConfigureDevice(&xga_isa_device, 0, qobject_cast<Settings*>(Settings::settings));
+    }
+}
+
 void SettingsDisplay::on_comboBoxVideo_currentIndexChanged(int index) {
     if (index < 0) {
         return;
@@ -126,8 +135,14 @@ void SettingsDisplay::on_comboBoxVideo_currentIndexChanged(int index) {
     ui->checkBoxXga->setEnabled(hasIsa16 || has_MCA);
     if (hasIsa16 || has_MCA)
         ui->checkBoxXga->setChecked(xga_enabled);
+
+    ui->pushButtonConfigureXga->setEnabled((hasIsa16 || has_MCA) && ui->checkBoxXga->isChecked());
 }
 
 void SettingsDisplay::on_checkBoxVoodoo_stateChanged(int state) {
     ui->pushButtonConfigureVoodoo->setEnabled(state == Qt::Checked);
 }
+
+void SettingsDisplay::on_checkBoxXga_stateChanged(int state) {
+    ui->pushButtonConfigureXga->setEnabled(state == Qt::Checked);
+}

src/qt/qt_settingsdisplay.hpp

@@ -22,8 +22,10 @@ public slots:
 
 private slots:
     void on_checkBoxVoodoo_stateChanged(int state);
+    void on_checkBoxXga_stateChanged(int state);
     void on_comboBoxVideo_currentIndexChanged(int index);
     void on_pushButtonConfigureVoodoo_clicked();
+    void on_pushButtonConfigureXga_clicked();
     void on_pushButtonConfigure_clicked();
 
 private:

src/qt/qt_settingsdisplay.ui

@@ -70,6 +70,13 @@
      </property>
     </widget>
    </item>
+   <item row="3" column="2">
+    <widget class="QPushButton" name="pushButtonConfigureXga">
+     <property name="text">
+      <string>Configure</string>
+     </property>
+    </widget>
+   </item>
    <item row="3" column="0" colspan="2">
     <widget class="QCheckBox" name="checkBoxXga">
      <property name="text">