Blender Git Loki

GPencil: Refactor: Add Swirl FX

The angle is no longer mulitplied by 8. We need to change the UI and patch
old files to preserve an appropriate slider feeling.

The Swirl FX (like others) is now affected by distance of the source object.

Transparent option has not been reimplemented as you can use masking for
that.

GPencil: Refactor: Add Flip FX

GPencil: Refactor: Add Colorize FX

The behavior has been changed quite a bit to work with separated
transparency layer.

- The custom mode now just blend between the original image and the
same image with the color changed and luma kept as is.
- Grayscale & Sepia mode now blend with the original image using the factor.
- The duo tone do not do a sharp separation of colors. It just color the
original in 2 different color using a hard separation threshold.

Cleanup: GPencil: CamelCase for uniform and fix a wrong comparison

GPencil: Refactor: Put blend mode shader code into gpencil_common_lib.glsl

This is because the rim fx needs the same code.

GPencil: Refactor: Add Rim FX

Nothing has changed functionality wise.

GPencil: Set default VFX Shadow color to Gray

Merge branch 'greasepencil-object' into greasepencil-refactor

Merge branch 'master' into greasepencil-object

GPencil: Remove arbitrary limit to only one VFX

GPencil: Change default values for Blur VFX

GPencil: Replace hardcoded factor by definition

Merge branch 'greasepencil-object' into greasepencil-refactor

Merge branch 'master' into greasepencil-object

GPencil: Refactor: Base implementation of VFX for gpencil

This new implementation is clearer and also process the colored alpha
compoment to preserve blending informations.

This is the base implementation containing a placeholder blur.

All the real effect implementation will follow in separate commits.

GPencil: Refactor: Add Glow effect

The glow effect is now additive. You cannot make black "glow" (whatever
that meant).

GPencil: Refactor: FX: make the Blur not dependant on sampling parameter

The sampling parameter was in fact use as iteration step count in previous
implementation. New behavior is much more consistent and predicatble

GPencil: Refactor: Add invert masking

GPencil: Refactor: Add Shadow Effect

All the parameters are now locked in world space following the object
center.

GPencil: Fix Layer UI