Qt/Debugger: Don't move entire list if it's not needed

With 4 buffer spaces at the bottom.

rpcs3/rpcs3qt/breakpoint_list.h

@@ -22,7 +22,7 @@ class breakpoint_list : public QListWidget
 	QColor m_text_color_bp;
 	QColor m_color_bp;
 Q_SIGNALS:
-	void RequestShowAddress(u32 addr);
+	void RequestShowAddress(u32 addr, bool force = false);
 public Q_SLOTS:
 	void HandleBreakpointRequest(u32 addr);
 private Q_SLOTS:

rpcs3/rpcs3qt/call_stack_list.h

@@ -16,7 +16,7 @@ class call_stack_list : public QListWidget
 	void UpdateCPUData(std::weak_ptr<cpu_thread> cpu, std::shared_ptr<CPUDisAsm> disasm);
 
 Q_SIGNALS:
-	void RequestShowAddress(u32 addr);
+	void RequestShowAddress(u32 addr, bool force = false);
 public Q_SLOTS:
 	void HandleUpdate(std::vector<u32> call_stack);
 private Q_SLOTS:

rpcs3/rpcs3qt/debugger_list.cpp

@@ -51,29 +51,38 @@ u32 debugger_list::GetCenteredAddress(u32 address) const
 	return address - ((m_item_count / 2) * 4);
 }
 
-void debugger_list::ShowAddress(u32 addr)
+void debugger_list::ShowAddress(u32 addr, bool force)
 {
 	auto IsBreakpoint = [this](u32 pc)
 	{
 		return m_breakpoint_handler->HasBreakpoint(pc);
 	};
 
-	if (xgui_settings->GetValue(gui::d_centerPC).toBool())
-	{
-		m_pc = GetCenteredAddress(addr);
-	}
-	else
+	const bool center_pc = xgui_settings->GetValue(gui::d_centerPC).toBool();
+
+	// How many spaces addr can move down without us needing to move the entire view
+	const u32 addr_margin = (m_item_count / (center_pc ? 2 : 1) - 4); // 4 is just a buffer of 4 spaces at the bottom
+
+	if (force || addr - m_pc > addr_margin * 4) // 4 is the number of bytes in each instruction
 	{
-		m_pc = addr;
+		if (center_pc)
+		{
+			m_pc = GetCenteredAddress(addr);
+		}
+		else
+		{
+			m_pc = addr;
+		}
 	}
 
 	const auto cpu = this->cpu.lock();
 
 	if (!cpu)
 	{
-		for (uint i = 0; i < m_item_count; ++i, m_pc += 4)
+		u32 pc = m_pc;
+		for (uint i = 0; i < m_item_count; ++i, pc += 4)
 		{
-			item(i)->setText(qstr(fmt::format("   [%08x] illegal address", m_pc)));
+			item(i)->setText(qstr(fmt::format("   [%08x] illegal address", pc)));
 		}
 	}
 	else
@@ -83,25 +92,27 @@ void debugger_list::ShowAddress(u32 addr)
 		const u32 address_limits = (is_spu ? 0x3fffc : ~3);
 		m_pc &= address_limits;
 		m_disasm->offset = vm::get_super_ptr(cpu_offset);
-		for (uint i = 0, count = 4; i<m_item_count; ++i, m_pc = (m_pc + count) & address_limits)
+		u32 pc = m_pc;
+
+		for (uint i = 0, count = 4; i<m_item_count; ++i, pc = (pc + count) & address_limits)
 		{
-			if (!vm::check_addr(cpu_offset + m_pc, 4))
+			if (!vm::check_addr(cpu_offset + pc, 4))
 			{
-				item(i)->setText((IsBreakpoint(m_pc) ? ">> " : "   ") + qstr(fmt::format("[%08x] illegal address", m_pc)));
+				item(i)->setText((IsBreakpoint(pc) ? ">> " : "   ") + qstr(fmt::format("[%08x] illegal address", pc)));
 				count = 4;
 				continue;
 			}
 
-			count = m_disasm->disasm(m_disasm->dump_pc = m_pc);
+			count = m_disasm->disasm(m_disasm->dump_pc = pc);
 
-			item(i)->setText((IsBreakpoint(m_pc) ? ">> " : "   ") + qstr(m_disasm->last_opcode));
+			item(i)->setText((IsBreakpoint(pc) ? ">> " : "   ") + qstr(m_disasm->last_opcode));
 
-			if (cpu->is_paused() && m_pc == GetPc())
+			if (cpu->is_paused() && pc == GetPc())
 			{
 				item(i)->setForeground(m_text_color_pc);
 				item(i)->setBackground(m_color_pc);
 			}
-			else if (IsBreakpoint(m_pc))
+			else if (IsBreakpoint(pc))
 			{
 				item(i)->setForeground(m_text_color_bp);
 				item(i)->setBackground(m_color_bp);
@@ -141,24 +152,22 @@ void debugger_list::mouseDoubleClickEvent(QMouseEvent* event)
 		int i = currentRow();
 		if (i < 0) return;
 
-		const u32 start_pc = m_pc - m_item_count * 4;
-		const u32 pc = start_pc + i * 4;
+		const u32 pc = m_pc + i * 4;
 
 		// Let debugger_frame know about breakpoint.
 		// Other option is to add to breakpoint manager directly and have a signal there instead.
 		// Either the flow goes from debugger_list->breakpoint_manager->debugger_frame, or it goes debugger_list->debugger_frame, and I felt this was easier to read for now.
 		Q_EMIT BreakpointRequested(pc);
-
-		ShowAddress(start_pc);
 	}
 }
 
 void debugger_list::wheelEvent(QWheelEvent* event)
 {
-	QPoint numSteps = event->angleDelta() / 8 / 15;	// http://doc.qt.io/qt-5/qwheelevent.html#pixelDelta
+	const QPoint numSteps = event->angleDelta() / 8 / 15;	// http://doc.qt.io/qt-5/qwheelevent.html#pixelDelta
 	const int value = numSteps.y();
+	const auto direction = (event->modifiers() == Qt::ControlModifier);
 
-	ShowAddress(m_pc - (event->modifiers() == Qt::ControlModifier ? m_item_count * (value + 1) : m_item_count + value) * 4);
+	ShowAddress(m_pc + (direction ? value : -value) * 4, true);
 }
 
 void debugger_list::resizeEvent(QResizeEvent* event)
@@ -185,5 +194,5 @@ void debugger_list::resizeEvent(QResizeEvent* event)
 		delete item(m_item_count);
 	}
 
-	ShowAddress(m_pc - m_item_count * 4);
+	ShowAddress(m_pc);
 }

rpcs3/rpcs3qt/debugger_list.h

@@ -28,7 +28,7 @@ class debugger_list : public QListWidget
 	debugger_list(QWidget* parent, std::shared_ptr<gui_settings> settings, breakpoint_handler* handler);
 	void UpdateCPUData(std::weak_ptr<cpu_thread> cpu, std::shared_ptr<CPUDisAsm> disasm);
 public Q_SLOTS:
-	void ShowAddress(u32 addr);
+	void ShowAddress(u32 addr, bool force = false);
 protected:
 	void keyPressEvent(QKeyEvent* event) override;
 	void mouseDoubleClickEvent(QMouseEvent* event) override;