Blender Git Loki

Fix stamp missing after multiview merge.

Was not using acquired render result correctly, most likely a copy paste
error.

Stamp cannot be written to file.

Make sure stamp data is avaliable before writing stamp to image - this
still does not fix stamp, looks like issue is availability of the images
themselves for the view, investigating next.

Tracking: Some more code de-duplication

Tracking: Code cleanup, de-duplicate some code in tracking context finish

Cleanup: pep8, spelling

Fix T44470: File Selection sometimes surpresses last Character.

Tweak hack of `file_draw_string()` (there may be better solution, but not worth
spending time on this, the whole filebrowser drawing code is to be rewritten anyway).

Fix T44475: Merge option of Mirror Modifier behavior reversed.

Glitch in rB57d9badc.

Logic Editor: Buttons for moving game properties up/down

D1163 by @panzergame, with minor edits by me (@Severin)

Tracking: Add missing plane track remapping when joining two point tracks

Tracking: Cleanup, move some plane tracks code to utility functions

BGE: scene.pre_draw_setup[] callback

This callback allows the user to change the camera data right before the
rendering calculations.

scene.pre_draw[] is not enough here, because if you want to change the
camera matrices (projection/modelview) the culling test is done before
that (after pre_draw_setup[] though).

Reviewers: moguri, campbellbarton

Differential Revision: https://developer.blender.org/D1251

Python sample code using this. The sample scene would need a default
camera (not used for rendering), a dummy camera ('Camera.VR'), and two
cameras ('Camera.Left', 'Camera.Right') that will be used for the actual
rendering.

```
import bge

def callback():
scene = bge.logic.getCurrentScene()
objects = scene.objects

vr_camera = objects.get('Camera.VR')

if bge.render.getStereoEye() == bge.render.LEFT_EYE:
camera = objects.get('Camera.Left')
else:
camera = objects.get('Camera.Right')

vr_camera.worldOrientation = camera.worldOrientation
vr_camera.worldPosition = camera.worldPosition

def init():
scene = bge.logic.getCurrentScene()
main_camera = scene.active_camera
main_camera.useViewport = True

scene.pre_draw_setup.append(callback)

objects = scene.objects
vr_camera = objects.get('Camera.VR')
vr_camera.useViewport = True
vr_camera.setViewport(
0,
0,
bge.render.getWindowWidth(),
bge.render.getWindowHeight() )
```

Tracking: Fix over-allocation in plane track's point tracks pointers when removing point track

Fix T44474: Rotation manipulator not hidden completely with all axes
locked

Really doesn't look like a bug on a first glance but the line of code
that was there previously seemed to be there to prevent the manipulator
from drawing in this case.

BLI_string: add BLI_snprintf_rlen

use when the length of the destination string is needed.

Math Lib: handling bits handling into own file

Minor edits to metadata commit

No need to calculate height of each line, just use height of font.

Initialize and use the theme for metadata text

Stamp refactoring:

Write those on render result during rendering, so we can cleanly write a
render result image after rendering.

Metadata:

* Theme support for metadata display
* Increase text DPI with scaling.

Metadata display support - patch by Julian and me.

Basically, blender adds a few metadata fields to images when
we render an image. Those metadata can now be viewed in the
image editor.

Also, made sure metadata are available when we write imbufs
to disc with "Save As". There may be more cases here that need
fixing, but this means that loading an image with metadata
will now properly preserve them in blender.