From 8c25712ea6131d19d7bb92a978ce7cda1c309404 Mon Sep 17 00:00:00 2001
From: Daniel Evans <danharibo@gmail.com>
Date: Tue, 11 Feb 2014 15:45:45 +0000
Subject: [PATCH] Viewport movement

---
 rwviewer/ViewerWidget.cpp | 34 ++++++++++++++++++++++++++++++++--
 rwviewer/ViewerWidget.hpp | 12 ++++++++++++
 2 files changed, 44 insertions(+), 2 deletions(-)

diff --git a/rwviewer/ViewerWidget.cpp b/rwviewer/ViewerWidget.cpp
index e244be96..9f2c1443 100644
--- a/rwviewer/ViewerWidget.cpp
+++ b/rwviewer/ViewerWidget.cpp
@@ -1,10 +1,11 @@
 #include "ViewerWidget.hpp"
 #include <render/Model.hpp>
 #include <glm/gtc/type_ptr.hpp>
+#include <QMouseEvent>
 
 ViewerWidget::ViewerWidget(QWidget* parent, const QGLWidget* shareWidget, Qt::WindowFlags f)
 : QGLWidget(parent, shareWidget, f), gworld(nullptr), currentModel(nullptr), 
- viewDistance(1.f), fm(ViewerWidget::UNK)
+ viewDistance(1.f), dragging(false), fm(ViewerWidget::UNK)
 {
 }
 
@@ -42,6 +43,8 @@ void ViewerWidget::paintGL()
 	r.camera.frustum.aspectRatio = width()/(height()*1.f);
 	
 	if(currentModel) {
+		glEnable(GL_DEPTH_TEST);
+		
 		glm::mat4 m;
 		
 		glUseProgram(r.worldProgram);
@@ -56,7 +59,8 @@ void ViewerWidget::paintGL()
 		glUniform1f(r.uniMatAmbient, 0.1f);
 		
 		glm::mat4 proj = r.camera.frustum.projection();
-		glm::mat4 view = glm::lookAt(glm::vec3(0.f, viewDistance, 0.f), glm::vec3(0.f, 0.f, 0.f), glm::vec3(0.f, 0.f, 1.f));
+		glm::vec3 eye(sin(viewAngles.x) * cos(viewAngles.y), cos(viewAngles.x) * cos(viewAngles.y), sin(viewAngles.y));
+		glm::mat4 view = glm::lookAt(eye * viewDistance, glm::vec3(0.f, 0.f, 0.f), glm::vec3(0.f, 0.f, 1.f));
 		glUniformMatrix4fv(r.uniView, 1, GL_FALSE, glm::value_ptr(view));
 		glUniformMatrix4fv(r.uniProj, 1, GL_FALSE, glm::value_ptr(proj));
 		
@@ -110,3 +114,29 @@ void ViewerWidget::showTXD(const QString& file)
 {
 	fm = ViewerWidget::TXD;
 }
+
+void ViewerWidget::mousePressEvent(QMouseEvent* e)
+{
+	dragging = true;
+	dstart = e->localPos();
+	dastart = viewAngles;
+}
+
+void ViewerWidget::mouseReleaseEvent(QMouseEvent*)
+{
+	dragging = false;
+}
+
+void ViewerWidget::mouseMoveEvent(QMouseEvent* e)
+{
+    if(dragging) {
+		auto d = e->localPos() - dstart;
+		viewAngles = dastart + glm::vec2(d.x(), d.y()) * 0.01f;
+	}
+}
+
+void ViewerWidget::wheelEvent(QWheelEvent* e)
+{
+	viewDistance = qMax(viewDistance - e->angleDelta().y() / 240.f, 1.f);
+}
+
diff --git a/rwviewer/ViewerWidget.hpp b/rwviewer/ViewerWidget.hpp
index d75be9ea..b88abf4f 100644
--- a/rwviewer/ViewerWidget.hpp
+++ b/rwviewer/ViewerWidget.hpp
@@ -19,6 +19,11 @@ class ViewerWidget : public QGLWidget
 	Model* currentModel;
 	
 	float viewDistance;
+	glm::vec2 viewAngles;
+	
+	bool dragging;
+	QPointF dstart;
+	glm::vec2 dastart;
 public:
 	
 	enum FileMode {
@@ -45,6 +50,13 @@ signals:
 
 	void fileOpened(const QString& file);
 
+protected:
+	
+	virtual void mousePressEvent(QMouseEvent*);
+	virtual void mouseReleaseEvent(QMouseEvent*);
+    virtual void mouseMoveEvent(QMouseEvent*);
+    virtual void wheelEvent(QWheelEvent*);
+
 private:
 	FileMode fm;
 };