Instead, add a gimp_layer_mode_get_format() function, which takes
the layer mode, composite space, and blend space, and returns the
I/O format.
Currently, we always use the composite space format as the I/O
format. This simplifies gimp_composite_blend(), and gives us
composite-space support for the "special" layer mode ops for free.
Replace the 'with-behind' and 'with-replace' properties with a
single 'context' property, and use it to select the included
layer modes, according to their context mask.
Add a dummy GIMP_LAYER_MODE_SEPARATOR value to the GimpLayerMode
enum, and use it to explicitly mark the menu separators in the
layer-mode group arrays; add separators to the layer-mode menu
accordingly.
Update the rest of the code to use 'context' instead of 'with-behind'
and 'with-replace'. In particular, in the layers and layer options
dialogs, select the right context based on whether or not the
selected layer is a group.
A bitmask, specifying in which contexts a layer mode is applicable.
Can be a combination of:
- LAYER: usable as a layer mode for actual layers.
- GROUP: usable as a layer mode for layer groups. Currently, all
modes that specify LAYER also specify GROUP, and vice versa,
but the planned pass-through mode will be GROUP only.
- PAINT: can be used as a paint mode.
- FADE: can be used for fading.
Add a 'context' field to _GimpLayerModeInfo, and provide context
masks to all the modes.
Use the context mask for validation when setting a layer's mode.
The next commit will use the mask when populating the layer mode
menus.
Add a "paint_composite_mode" field to GimpLayerModeInfo and set the
mode of the eraser to SRC_ATOP. Defaulting to SRC_OVER for all
painting didn't quite do it for all modes.
set all legacy modes to completely immutable and the LAB modes'
blend mode to immutable. Change GimpLayer setters and the UI
accordingly. Remove the LAB color spaces from the GUI, they can
only be used with the LAB blend modes anyway and not changed.
They can be affected by the same problem described in
commit 4c3a772cd8, although in the
case of SRC_ATOP, the affected pixels are always fully transparent.
When the source alpha is zero, we don't calculate the blended color,
so `comp[b]` can be infinite or NaN, in which case the expression
`in[ALPHA] * (comp[b] - layer[b])` is NaN, rather than the expected
value of zero.
and to operations/layer-modes/, respectively.
Add gimp_layer_modes_init() which asserts on the correct order of the
GimpLayerModeInfo array, and switch to accessing the array directly in
gimp_layer_mode_info().
Similar to the Photoshop mode of the same name. Assigns
either 0 or 1 to each of the channels, depending on whether the
sum of source and destination channel values is less than, or
greater than (or equals to), one, respectively.
This is equivalent to inverting the source, and using it to perform
per-pixel, per-channel threshold against the destination, which is
useful for various effects.
Stuff like passing "input" directly if "aux"'s opacity is 0, etc.
Used to be partly handled by normal mode, even though it applies
to other modes too.
Adjust the logic for the new compositing modes.
Add a GimpLayerModeAffectMask enum, and a corresponding
get_affect_mask() function to GimpOperationLayerMode, which
specifies which of the op's inputs, if any, are affected by the
mode, apart from the overlapping regions. Most modes affect only
the overlapping regions, but dissolve and replace also affect the
rest of the input. This information is used for determining if
the optimizations are applicable.
Some of the generic files still contain SSE2 code, in particular
gimpoperationlayermode.c. The reason why it often works without is that
native gcc will usually pre-define SSE macros by default.
To check this: gcc -dM -E - < /dev/null | grep SSE
Yet I had a case on a small netbook where the SSE macros were not
pre-defined even though supported. Consequently the build failed.
These variations on darken only and lighten only have the advantage over the
componentvise versions that they always use the full triplet of either original
or new layer - meaning no new colors/hues will be introduced. This is similar
to how these modes operated/operates in picture publisher and photo-paint.
... is fully transparent, instead of just src.
The blend func results only affect the intersection of dest and src.
Run time is currently dominated by the compositing step for most modes,
so the difference in performance is pretty negligible, but it does make
a difference for the more expensive modes, like the HSV ones.
For operations needing to override default behavior sub-classes should still be
used.
This commit also enables pinligh, vividlight and linearlight blend mode modes
