ui: Add the gfx::Vector3dF class.

ui: Add the gfx::Vector3dF class.

This class represents a distance along 3 dimensions. It supports operations
such as the cross product and dot product between two such vectors, in addition
to the standard operations also supported by the Vector2dF class.

BUG=147395
R=sky,pkasting


Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=165402

[danakj, 2012-11-01 00:17:50]

+cc-bugs

[Peter Kasting, 2012-11-01 00:24:58]

LGTM

This makes me wonder offhand if we should have functions (in 2 and 3 dimensions)
for the unit vector in the direction of a given vector, as well as the
projection of a vector on another vector.

https://codereview.chromium.org/11367025/diff/1/ui/gfx/vector3d_f.cc
File ui/gfx/vector3d_f.cc (right):

https://codereview.chromium.org/11367025/diff/1/ui/gfx/vector3d_f.cc#newcode69
ui/gfx/vector3d_f.cc:69: float z = x_ * other.y() - y_ * other.x();
Nit: You could write |z_| directly here and omit that from below, if you want. 
I don't care too much about parallel structure...

https://codereview.chromium.org/11367025/diff/1/ui/gfx/vector3d_f.h
File ui/gfx/vector3d_f.h (right):

https://codereview.chromium.org/11367025/diff/1/ui/gfx/vector3d_f.h#newcode96
ui/gfx/vector3d_f.h:96: UI_EXPORT float DotProduct(const Vector3dF& lhs, const
Vector3dF& rhs);
Should we add this for 2D vectors too?

[danakj, 2012-11-01 00:39:53]

We've got a method for projecting a vector onto another vector in cc/math_util.h
right now. Shawn will be moving all that functionality out into ui/gfx at some
point.

https://codereview.chromium.org/11367025/diff/1/ui/gfx/vector3d_f.h
File ui/gfx/vector3d_f.h (right):

https://codereview.chromium.org/11367025/diff/1/ui/gfx/vector3d_f.h#newcode96
ui/gfx/vector3d_f.h:96: UI_EXPORT float DotProduct(const Vector3dF& lhs, const
Vector3dF& rhs);
On 2012/11/01 00:24:58, Peter Kasting wrote:
> Should we add this for 2D vectors too?

We could, but without any call sites?

[Peter Kasting, 2012-11-01 01:33:28]

https://codereview.chromium.org/11367025/diff/1/ui/gfx/vector3d_f.h
File ui/gfx/vector3d_f.h (right):

https://codereview.chromium.org/11367025/diff/1/ui/gfx/vector3d_f.h#newcode96
ui/gfx/vector3d_f.h:96: UI_EXPORT float DotProduct(const Vector3dF& lhs, const
Vector3dF& rhs);
On 2012/11/01 00:39:53, danakj wrote:
> On 2012/11/01 00:24:58, Peter Kasting wrote:
> > Should we add this for 2D vectors too?
> 
> We could, but without any call sites?

Just didn't know if you'd need it.  If not don't worry about it.

[danakj, 2012-11-01 01:36:23]

I added some point math similar to 2d points, with vectors:
Point3F - Point3F
Point3F + Vector3dF
Point3F - Vector3dF

PTAL

https://codereview.chromium.org/11367025/diff/1/ui/gfx/vector3d_f.h
File ui/gfx/vector3d_f.h (right):

https://codereview.chromium.org/11367025/diff/1/ui/gfx/vector3d_f.h#newcode96
ui/gfx/vector3d_f.h:96: UI_EXPORT float DotProduct(const Vector3dF& lhs, const
Vector3dF& rhs);
On 2012/11/01 01:33:28, Peter Kasting wrote:
> On 2012/11/01 00:39:53, danakj wrote:
> > On 2012/11/01 00:24:58, Peter Kasting wrote:
> > > Should we add this for 2D vectors too?
> > 
> > We could, but without any call sites?
> 
> Just didn't know if you'd need it.  If not don't worry about it.

Ya, only code doing dot products for cc/ at the moment is doing it with 3d
points. :)

[Peter Kasting, 2012-11-01 01:38:49]

LGTM.  Note that your classes should only have ToString() methods if you
actually need those (maybe unittests do).

[danakj, 2012-11-01 01:40:50]

sky can you please take a look for OWNERS?

On 2012/11/01 01:38:49, Peter Kasting wrote:
> LGTM.  Note that your classes should only have ToString() methods if you
> actually need those (maybe unittests do).

Yup! I added a point3_unittest that uses it (missed it last upload). Thanks.

[sky, 2012-11-01 15:53:01]

LGTM

[danakj, 2012-11-01 15:54:16]

thanks!

[commit-bot: I haz the power, 2012-11-01 15:54:24]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/danakj@chromium.org/11367025/9009

[commit-bot: I haz the power, 2012-11-01 17:06:58]

Change committed as 165402