Blender Git Loki

Fix doing too many invalidations of brush image cache. Having separate
flags for mask/image helps here.

Fix issue reported on blenderartists: 2d painting does not respect the
brush strength when masking is off. I hope behaviour will at last be
consistent in every case now.

Add missing notification event for colour flipping

Fix sample color operator sampling brush colour. Temporarily turn brush
display off while the operator is running.

Optimizations for image paint undo stack for drag dot/anchored strokes

* Skip copy of undo tile to temorary buffer when restoring. Gives a nice
speedup.
* When we restore the image from undo tiles, make tiles invalid. On undo
push end, invalid tiles get deleted. This solves saving too many tiles
in the case where user could happilly drag the dot all around the image.

Refactor:
* Draw pressure is handled in stroke level.
* Anchored brush drawing is correctly handled outside sculpt mode too.

Drag dot strokes for image painting.

This was mostly working with undo code.

There is a tradeoff between doing undo traversal for images vs undo
initialiatio time:

The more area the user paints on, the more undo tiles are added to the
system. That makes restoring of the image slower after each step.
A way to optimize this is to completely delete the undo tiles after each
step. This also will make the undo steps use less memory.

However given that for a realistic, non-user-testing use case, the dabs
will be localized, better optimize the initialization case. In
projective texturing, which is the most performance hungry, indeed this
helps with performance, provided the use case is sane. I left the
clearing code ifdefed out just in case.

Also exposed anchored stroke options. They work with texture coordinates
well but not with paint brush size yet.

Merge trunk -r57861 into soc-2013-paint

Sampling for image painting:

Modify the algorithm so that in 3d viewport, it first attempts to sample
the color from the texture assigned to the picked face, if any. This
solves the issue of getting a darker colour than the one requested,
usually due to viewport shading.

Necromancy exercice no #$%^&@!**#$>:3. Resurrect feature from old GSOC
onion branch that applies gravity after each dab in sculpt mode. I am
not very fond of the result, it will need artist feedback and testing.

merge with trunk -r 57777

Fix 2d masking for pressure masking, also change pressure cutoff so that
high luminance areas show up first when pressure increases.

Better exposing of accumulation option according to brush settings.

Change masking of 2d painting to be similar to 3d masking.

This fixes inconsistent behaviour where opacity masking is done using
only the curve and alpha offset when view mask mapping is used in 2d
painting. The key notion here is that masking converges to the maximum
value, which should be texmask*brush_alpha here. This happens already
for projective texturing.

Unfortunately this requires an extra allocation of a maximum mask value
imbuf during a stroke which introduces some performance regression when
using mask inages. This first version of the fix does not yet introduce
partial update of this maximum mask buffer like we do for colour image
buffers, and even though this bug exists in trunk as well, I decided to
only commit in this branch because it is not too obvious and because
there is some performance regression when using mask brushes.

Also, this commit may break pressure masking because I don't have a
tablet right now to test. Don't panic if this breaks it, I will fix it
when I get my hands on it again. However if this is not the case, this
commit should also fix the 2d behaviour of ramp style pressure masking.

Merge trunk -r57697 into soc-2013-paint

Merge trunk -r 57692 into soc-2013-paint

Yet another fix for mask pressure:

Tiled colour texture could activate partial update, make sure to test
separately for mask pressure options and always disable if they are
active.

Yet another small fix for 2d painting with mask pressure: Make sure the
brush texture is recreated always in that case (possibly should check
the actual brush pressure but it will make little difference).

Applying patch by Fredrik Hansson: Extra blend modes.

Actually should be called the blend mode imperialism commit, this commit
adds no more no less about 15 new blend modes.

The catch is that the float versions will probably have to work in
display colour spaces, but seeing how the rest of the blending code is I
think this can go in right now.

Thanks to Fredrik for the original patch and to Campbell for writing
uncrustify. A solid weapon in the war against the non-blender-style-

To painters out there: Test this extensively!

Fix blenderplayer link issue