Calculate an accurate up vector for the camera

2 files changed, 23 insertions, 4 deletions

diff --git a/gfx/gl/camera.cpp b/gfx/gl/camera.cpp
index fadbfd7..69cfe35 100644
--- a/gfx/gl/camera.cpp
+++ b/gfx/gl/camera.cpp
@@ -25,3 +25,10 @@ Camera::updateView()
 	viewProjection = projection * view;
 	inverseViewProjection = glm::inverse(viewProjection);
 }
+
+glm::vec3
+Camera::upFromForward(const glm::vec3 & forward)
+{
+	const auto right = glm::cross(forward, ::down);
+	return glm::cross(forward, right);
+}
diff --git a/gfx/gl/camera.h b/gfx/gl/camera.h
index 3182969..2d937a0 100644
--- a/gfx/gl/camera.h
+++ b/gfx/gl/camera.h
@@ -24,18 +24,28 @@ public:
 	void

 	setForward(const glm::vec3 & f)

 	{

-		forward = f;

-		updateView();

+		setForward(f, upFromForward(f));

 	}

 	void

-	setView(const glm::vec3 & p, const glm::vec3 & f, const glm::vec3 & u = ::up)

+	setForward(const glm::vec3 & f, const glm::vec3 & u)

 	{

-		position = p;

 		forward = f;

 		up = u;

 		updateView();

 	}

 	void

+	setView(const glm::vec3 & p, const glm::vec3 & f)

+	{

+		position = p;

+		setForward(f);

+	}

+	void

+	setView(const glm::vec3 & p, const glm::vec3 & f, const glm::vec3 & u)

+	{

+		position = p;

+		setView(f, u);

+	}

+	void

 	lookAt(const glm::vec3 & target)

 	{

 		setForward(glm::normalize(target - position));

@@ -51,6 +61,8 @@ public:
 		return position;

 	}

 

+	static glm::vec3 upFromForward(const glm::vec3 & forward);

+

 private:

 	void updateView();