From ea1ce7b0fb7709ae56977480821ac96a231a0686 Mon Sep 17 00:00:00 2001
From: Daniel Karbach <daniel.karbach@localhorst.tv>
Date: Thu, 12 Feb 2015 22:13:25 +0100
Subject: [PATCH] mouse controlled camera pitch/yaw

---
 src/app.cpp    | 10 ++++++++++
 src/app.hpp    |  3 +++
 src/camera.cpp |  8 +++-----
 src/camera.hpp | 18 ++++++++++++------
 src/init.cpp   | 20 ++++++++++++++++++++
 src/init.hpp   |  6 ++++++
 src/model.hpp  |  2 ++
 7 files changed, 56 insertions(+), 11 deletions(-)

diff --git a/src/app.cpp b/src/app.cpp
index 038aa1a..ff5a3be 100644
--- a/src/app.cpp
+++ b/src/app.cpp
@@ -24,6 +24,8 @@ Application::Application()
 , ctx(window.CreateContext())
 , init_glew()
 , program()
+, pitch_sensitivity(-0.0025f)
+, yaw_sensitivity(-0.001f)
 , cam()
 , model()
 , vtx_buf(0)
@@ -63,6 +65,7 @@ Application::Application()
 	glBufferData(GL_ARRAY_BUFFER, sizeof(vtx_coords), vtx_coords, GL_STATIC_DRAW);
 
 	model.Position(glm::vec3(0, 0, -4));
+	cam.Position(glm::vec3(0, 0, 4));
 
 	mvp_handle = program.UniformLocation("MVP");
 
@@ -77,6 +80,7 @@ Application::~Application() {
 void Application::Run() {
 	running = true;
 	Uint32 last = SDL_GetTicks();
+	window.GrabMouse();
 	while (running) {
 		Uint32 now = SDL_GetTicks();
 		int delta = now - last;
@@ -95,6 +99,12 @@ void Application::HandleEvents() {
 	SDL_Event event;
 	while (SDL_PollEvent(&event)) {
 		switch (event.type) {
+			case SDL_MOUSEMOTION:
+				cam.RotateYaw(event.motion.xrel * yaw_sensitivity);
+				cam.RotatePitch(event.motion.yrel * pitch_sensitivity);
+				std::cout << "x: " << event.motion.xrel << ", y: " << event.motion.yrel
+						<< ", pitch: " << cam.Pitch() << ", yaw: " << cam.Yaw() << std::endl;
+				break;
 			case SDL_QUIT:
 				running = false;
 				break;
diff --git a/src/app.hpp b/src/app.hpp
index 4e381a2..8bafb23 100644
--- a/src/app.hpp
+++ b/src/app.hpp
@@ -36,6 +36,9 @@ private:
 	InitGLEW init_glew;
 	Program program;
 
+	float pitch_sensitivity;
+	float yaw_sensitivity;
+
 	Camera cam;
 	Model model;
 
diff --git a/src/camera.cpp b/src/camera.cpp
index 8309fe6..21df874 100644
--- a/src/camera.cpp
+++ b/src/camera.cpp
@@ -11,11 +11,9 @@ Camera::Camera()
 , aspect(1.0f)
 , near_clip(0.1f)
 , far_clip(100.0f)
-, position(0, 0, 0)
-, target(0, 0, -1)
-, up(0, 1, 0)
+, model()
 , projection(glm::perspective(fov, aspect, near_clip, far_clip))
-, view(glm::lookAt(position, target, up))
+, view(model.Transform())
 , vp(projection * view) {
 
 }
@@ -61,7 +59,7 @@ void Camera::UpdateProjection() {
 }
 
 void Camera::UpdateView() {
-	view = glm::lookAt(position, target, up);
+	view = glm::inverse(model.Transform());
 	vp = projection * view;
 }
 
diff --git a/src/camera.hpp b/src/camera.hpp
index 5be71e2..88da8ca 100644
--- a/src/camera.hpp
+++ b/src/camera.hpp
@@ -3,6 +3,8 @@
 
 #include <glm/glm.hpp>
 
+#include "model.hpp"
+
 
 namespace blank {
 
@@ -25,10 +27,16 @@ public:
 	void Aspect(float w, float h);
 	void Clip(float near, float far);
 
-	void Position(glm::vec3 pos) { position = pos; UpdateView(); }
-	void Move(glm::vec3 delta) { position += delta; UpdateView(); }
+	void Position(glm::vec3 pos) { model.Position(pos); UpdateView(); }
+	void Move(glm::vec3 delta) { model.Move(delta); UpdateView(); }
 
-	void LookAt(glm::vec3 tgt) { target = tgt; UpdateView(); }
+	// all angles in radians (full circle = 2π)
+	float Pitch() const { return model.Pitch(); }
+	void Pitch(float p) { model.Pitch(p); UpdateView(); }
+	void RotatePitch(float delta) { model.RotatePitch(delta); UpdateView(); }
+	float Yaw() const { return model.Yaw(); }
+	void Yaw(float y) { model.Yaw(y); UpdateView(); }
+	void RotateYaw(float delta) { model.RotateYaw(delta); UpdateView(); }
 
 private:
 	void UpdateProjection();
@@ -40,9 +48,7 @@ private:
 	float near_clip;
 	float far_clip;
 
-	glm::vec3 position;
-	glm::vec3 target;
-	glm::vec3 up;
+	Model model;
 
 	glm::mat4 projection;
 	glm::mat4 view;
diff --git a/src/init.cpp b/src/init.cpp
index 20f4fe4..4772898 100644
--- a/src/init.cpp
+++ b/src/init.cpp
@@ -83,6 +83,26 @@ Window::~Window() {
 	SDL_DestroyWindow(handle);
 }
 
+void Window::GrabInput() {
+	SDL_SetWindowGrab(handle, SDL_TRUE);
+}
+
+void Window::ReleaseInput() {
+	SDL_SetWindowGrab(handle, SDL_FALSE);
+}
+
+void Window::GrabMouse() {
+	if (SDL_SetRelativeMouseMode(SDL_TRUE) != 0) {
+		sdl_error("SDL_SetRelativeMouseMode");
+	}
+}
+
+void Window::ReleaseMouse() {
+	if (SDL_SetRelativeMouseMode(SDL_FALSE) != 0) {
+		sdl_error("SDL_SetRelativeMouseMode");
+	}
+}
+
 GLContext Window::CreateContext() {
 	return GLContext(handle);
 }
diff --git a/src/init.hpp b/src/init.hpp
index bf6191b..a2f2de7 100644
--- a/src/init.hpp
+++ b/src/init.hpp
@@ -54,6 +54,12 @@ public:
 	Window(const Window &) = delete;
 	Window &operator =(const Window &) = delete;
 
+	void GrabInput();
+	void ReleaseInput();
+
+	void GrabMouse();
+	void ReleaseMouse();
+
 	GLContext CreateContext();
 
 	void Flip();
diff --git a/src/model.hpp b/src/model.hpp
index c0bda41..938fd44 100644
--- a/src/model.hpp
+++ b/src/model.hpp
@@ -18,8 +18,10 @@ public:
 	void Move(glm::vec3 delta) { position += delta; }
 
 	// all angles in radians (full circle = 2π)
+	float Pitch() const { return pitch; }
 	void Pitch(float p) { pitch = p; }
 	void RotatePitch(float delta) { pitch += delta; }
+	float Yaw() const { return yaw; }
 	void Yaw(float y) { yaw = y; }
 	void RotateYaw(float delta) { yaw += delta; }
 
-- 
2.39.2