Difference between revisions of "Tiling tool"

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(Implementation: Changes to make more sense from programming POV? (though I may be saying nonsense))
 
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{{DevDiscussion}}
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== Tiling tool ==
 +
The current tiling interface is hard to use. The current interface attempts to make the process more user friendly through the use of a tool that creates a "render frame", which consists of two parts:
 +
* A base tile, where the pattern is supposed to be
 +
* A more general render frame, showing the location of the output
 +
* Both can be edited on-canvas
  
== Symmetry and Tile tool ==
+
The tiling process is simply:
 +
# Create a frame
 +
# Select a pattern and a frame
 +
# Click "Render" from the tiling tool
  
The current tile interface is hard to use. The current proposal for Symmetry and Tiles tool seeks to expand upon its uses while proposing an interface that is easy to use. This proposal proposes 4 modes or sub-tools:
+
* By default the frame becomes invisible after a render, and becomes "implied" in the generated output (a bit like clipping?).
 +
* Undoing the render makes the frame appear again.
 +
* The user can choose to drop a copy of the frame after a render for re-use however, or make a copy before applying.
  
{| class="wikitable"
+
{| class="wikitable"  
! | Tool
+
|+
! | Description
+
! scope="col" width="180"| Type
 +
! scope="col" width="700" | Description
 
|-
 
|-
! Symmetry
+
! Wallpaper tiling
| This tool is destined for users who just want some basic symmetries. Use cases include pattern design and technical drawing.
+
| Allows users to use the 17 wallpaper types.
 
|-
 
|-
! Tiling
+
! Radial tiling
| This tool allows users to use the 17 wallpaper types.
+
|  
 +
* This is for radial designs, and allows both angular clones and radial clones.
 +
* For angular clones, users can choose between simple rotation or symmetry + rotation. (thus covering the Rosetta patterns as well)
 +
* For radial clones, users can choose between same direction and alternating directions.
 
|-
 
|-
! Radial clones
+
! Path tiling
| This is for radial designs, and uses polar coordinates.
+
|  
|-
+
* Clones are generated along a path. This can be used to create a string of decorations, for repeating frills, for page borders etc.
! Clone along path
+
* Users can choose from all 7 Frieze groups.
| Clones are created along a path. This can be used to create a string of decorations, for repeating frill designs, for page borders etc.
+
|}  
|}
+
  
== General behaviour ==
+
[[File:Tiling_Tool_Toolbar.png|UI Proposal for tiling tool]]
 +
<br clear="all"/>
  
Applying any Symmetry or Tile results in the following behaviour:
+
[[Media:WallpaperTransformations.png | Transformation images for wallpaper groups]]
* If the object isn't a group, a group is made out of the selected object. This allows the user to enter the group and add extra elements.
+
* A corresponding guide is generated. This guide can be edited with the Tile and Symmetry tool. All guides can be resized or rotated, but further transformations depend on the guide type.
+
* Copies are generated from the original object.
+
* The original and its copies can be selected and grouped, and a new transformation can be applied to the group. This allows, for example, for a user to create a symmetrical pattern then use it as a tile.
+
  
== Symmetry or tiling options ==
+
== Render modes ==
  
[http://postimage.org/image/9w57ujh1l/ List of Toolbar designs]
+
There are two modes:
 +
* Create clones: This is the current rendering mode
 +
* Fuse: This mode first cuts excess for "inner" sides, then performs a "fuse" operation on the whole output.
  
=== Symmetry or tiling type ===
+
[[File:Tiling_cut_excess.png|Explanation of "Fuse" feature for tiling proposal]]
 +
<br clear="all"/>
  
{| class="wikitable"
+
[[File:Tiling_interface_examples.png|More examples of the possible outputs for the “Fuse Cut” mode]]
|+ Tool comparisons
+
<br clear="all"/>
! Tool
+
 
! Available options
+
== Render frame ==
! Guides
+
 
! Notes
+
The render frame is made up of:
 +
* A central tile, which defines the location of the pattern to copy
 +
* A more general render grid
 +
 
 +
[[File:Tiling_Tool_Render_Frame.png|UI Proposal for the Render frame of the Tiling tool proposal]]
 +
<br clear="all"/>
 +
 
 +
== On-canvas transformation handles ==
 +
 
 +
[[File:Tiling_Tool_Transformation_Handles.png|UI proposal for on-canvas handles for the tiling tool proposal]]
 +
<br clear="all"/>
 +
 
 +
== Guide points ==
 +
 
 +
[[File:Tiling_Tool_Guides.png|UI proposal for guide points feature for Tiling Tool]]
 +
<br clear="all"/>
 +
 
 +
Guide points are there to serve as reference point when creating tile designs.
 +
* When you add a guide point, "counterparts" are generated in all the other tiles
 +
* Ctrl-drag to drag out a segment.
 +
* The idea is that users can snap guide points along tile edges, snap a node of the pattern to that guide and snap the node handle to the end of the guide segment, then repeat with the guide point's counterparts. This should help easily create seamless transitions.
 +
 
 +
== Option for dynamics Symmetry around base tile? ==
 +
 
 +
Proposal: option for all dynamics to be rendered in a symmetry around the base tile. This proposal is because users may want tiles to fade around a central tile. Rendering the frame in just one direction is easy, but achieving the symmetry otherwise is not.
 +
 
 +
The main difficulty is that the current dynamics mechanism is linear, so adjustments would be needed.
 +
 
 +
[[File:Tiling Tool Symmetry.png|Proposal for dynamics to occur in a symmetry around the base tile for the tiling tool]]
 +
<br clear="all"/>
 +
 
 +
== On-canvas dynamics editing ==
 +
 
 +
Currently the two following approaches to on-canvas dynamics editing have been considered:
 +
# Edit a tile of the render frame (rotate and resize for example), all other tiles in the render frame are updated dynamically to give you an idea of the result.
 +
#* Pros: high preview value, as the outline of the tiles by themselves should give an idea as to the output of the whole tiling.
 +
#* Cons: forcing live update of tiles may be slow, and big displacements of tiles are distracting from the editing process. Worse if jitters are also visualized on-canvas.
 +
# Edit only one or two "reference" tiles. None of the other tiles change. Inkscape deduces transformation values from there and converts them into values for the existing tiling mechanism.
 +
#* Pros: less taxing on the interface.
 +
#* Cons: Less preview value.
 +
 
 +
Tom Lechner made a possible mock-up for the second option: [http://www.tomlechner.com/randompics/finishing.png Mock-up for on-canvas tile dynamics editing]
 +
 
 +
It could be possible to combine the best of both worlds with a "Dynamics preview" mode (so it's a preview of the dynamics, not of the pattern getting tiled):
 +
* When preview mode is on, Inkscape generates a preview of the render frame's tiles with dynamics applied, including jitters.
 +
* Editing is not allowed. You have to exit the preview mode to make other adjustments.
 +
* The idea is that some complex tilings will probably take a long time to render. This preview mode gives a quick idea about the outcome without having to do a full render, then undo, adjust and re-render again.
 +
 
 +
[[File:Tiling Tool Dynamics Preview Mode.png|Preview mode for dynamics for the Tiling Tool proposal]]
 +
<br clear="all"/>
 +
 
 +
== Radial tiling ==
 +
 
 +
In theory, radial tiling could use the same mechanism as rows and columns tiling, by converting all input into X, Y input. Although users can also use rows and columns tiling to achieve radial tiling, doing so would not be very intuitive.
 +
 
 +
[[File:Tiling Tool Radial Tiling.png|UI proposal for radial tiling in the tiling tool]]
 +
<br clear="all"/>
 +
 
 +
== Line tiling ==
 +
 
 +
Implementing line tiling would be more complicated that implementing radial tiling, because it is an extension of the Pattern Along Path function rather than of the existing tiled clones mechanism. So, the programer would have to figure out a way to combine Pattern Along Path and the dynamics for Tiled Clones, all the while implementing the proper render guide. If he achieves it though, it'd be an amazingly powerful and versatile tool for designers of all kinds.
 +
 
 +
Line tiling actually comes in two sets of guides:
 +
* A pattern guide.
 +
* A target guide. This target guide appears over the target path, which has to be copied first to the clipboard.
 +
 
 +
The pattern guide can actually be edited independently of a target path, but unless a target path is copied to the clipboard, the user cannot render the line tiling. So, the user can first adjust the pattern design and tiling properties, then copy a path, adjust and apply.
 +
 
 +
[[File:Tiling tool line tiling.png|UI proposal for line tiling in the tiling tool]]
 +
<br clear="all"/>
 +
 
 +
== Tile stacking ==
 +
 
 +
You can stack different tilings!  
 +
 
 +
[[File:Tiling stacking.png|Explanation of tile stacking feature for my tiling proposal]] <br clear="all"/>
 +
 
 +
Inkscape will likely have an Effects stacking mechanism in the future. Whatever it is, tiling would also fit right into it.
 +
 
 +
== Line patterns ==
 +
 
 +
And why not "line patterns" while we're at it?
 +
 
 +
[[File:Tiling line patterns.png|UI proposal for line pattern choosing]] <br clear="all"/>
 +
 
 +
== UI design status ==
 +
 
 +
This section is a summary of how ready the UI proposal for the various features are (as well as comments about coding):
 +
 
 +
'''General concept and tiling methods:'''
 +
 
 +
{| class="wikitable"
 +
|+
 +
! scope="col" width="180" | Feature
 +
! scope="col" width="600" | Status
 
|-
 
|-
! Symmetry
+
! General concept
|  
+
| Valerie: The current interface is the result of exploring several very different concepts with inputs and criticism by a number of people. The "On-canvas editable central tile + render frame" concept is currently the first of these concepts to have encountered no major objections as to its usability, so it should be safe to consider this an acceptable general direction unless a better proposal comes along.
* X Symmetry
+
* Y Symmetry
+
* Point Symmetry
+
| Inkscape internally keeps track of an X-axis and a Y-axis, using their intersection for point symmetry. The X/Y axis group can be rotated.
+
|
+
* Inkscape generates an X and Y axis, aligned by default to the bottom-right of the object's bounding box.
+
* The 3 symmetry types can be simply toggled on and off. They can all be chosen at the same time.
+
 
|-
 
|-
! Tiling
+
! Wallpaper tiling
| All 17 tiling options available.
+
| Valerie: The general proposal (base tile, handles + render frame) doesn't seem to generate many objections. The exact form of the handles and the details about manipulation could still be refined.
| Inkscape generates a guide specific to the transformation type upon application of the tiling. This guide remains editable on-canvas with the Symmetry and Tiling tool.
+
| Because the 17 tiling options use different guide shapes, tiling does not give an option to select existing guides on-canvas.  
+
 
|-
 
|-
! Radial Clones
+
! Radial tiling
|  
+
| Valerie: Not much input yet.
* None
+
* Simple symmetry
+
* Symmetry + rotate
+
| Inkscape generates an angle guide that by defaut is centered on the object's center of rotation. The user can control both the center and the angle of the guide. Two default orientations are available.
+
|
+
* By default, the Radial Clone type is "none." Just Select simple rotation or Symmetry + rotate to apply desired radial clone.
+
* Rather than specify a base angle, the toolbar asks you to specify the number of times the sphere must be divided by (example: 60). The reasoning behind this is that it's more intuitive for most users, and avoids rounding problems.
+
* You can enter a number of copies higher than the number of divisions (for example, when Dynamics are applied)
+
* All advanced transformations are according to polar coordinates.
+
 
|-
 
|-
! Clones Along Path
+
! Line tiling
|  
+
| Valerie: Not much input yet. There should be, as this is a potentially very powerful feature for designers, though also hard to implement.
* Fixed distance
+
|}
* Clone at each node along the path
+
 
| A path must be selected when "Clones Along Path" is applied
+
'''Specific features (all tiling methods)'''
| By default, the point at which the clones snap to the selected path is its rotation center. All advanced transformations use Normal/Tangential coordinates.
+
 
 +
{| class="wikitable"
 +
|+
 +
! scope="col" width="180" | Feature
 +
! scope="col" width="600" | Status
 +
|-
 +
! Fuse mode
 +
| Valerie: General input seems to be that this is a "good idea."
 +
|-
 +
! Guide points
 +
| Valerie: General input seems to be that this is a "good idea."
 +
|-
 +
! On-canvas handling of dynamics
 +
| Valerie: Concensus is that on-canvas manipulation of dynamics is very desirable. However, the exact form is still up to debate. Tom Lechner has a proposal that will allow to visualize most elements, but more work is needed to establish a mechanism for visualizing and controlling jitter as well.
 +
|-
 +
! Multi-Stop Interpolation Gradient (multi-stop dynamics)
 +
| Valerie: Such a mechanism would require reworking the entire tiling mechanism. The only bright side is that Inkscape doesn't store any tiling information, so changing the mechanism won't break backwards compatibility. See Jasper's detailed comment in "Implementation."
 +
|-
 +
! Symmetrical dynamics output around base tile
 +
| Valerie: Looking at Jasper's explanation below, symmetrical dynamics around a central tile basically aren't supported by the current mechanism.
 +
|-
 +
! Tile stacking and line pattern management
 +
| Valerie: At this point both are just suggestions, as Inkscape has neither the mechanisms in place nor an UI.
 +
|}
 +
 
 +
'''Implementation comments'''
 +
 
 +
{| class="wikitable"
 +
|+
 +
! scope="col" width="180" | Feature
 +
! scope="col" width="600" | Comments
 +
|-
 +
! Multi-Stop Interpolation Gradient
 +
| Jasper (mail from mailing list): All the code is in src/ui/dialog/clonetiler.cpp. The main function is CloneTiler::clonetiler_get_transform. This function essentially gets all info, as well as a row and column index. It then computes all the transforms required for that position and combines them. As far as I can tell it combines them in such a way that first a scaling is applied, then a rotation and finally a translation. If you select a different symmetry group then the translation can become a more complicated transform.
 +
 
 +
The scheme we talked about earlier that would interpolate transforms is not necessarily compatible. This is because in the latter the case the entire transform would be interpolated, while what Inkscape does is essentially interpolating per kind of transform. That this is not the same can be seen by realizing that rotate(50)translate(1)rotate(50)translate(1) is not the same as rotate(100)translate(2). The former is more or less what we talked about (or at least what I had in mind during that discussion), the latter is what Inkscape does.
 +
 
 +
However, Inkscape currently seems to store almost nothing about the tiling in the file. So it would be relatively benign to change behaviour. Existing files would not be affected in any way, users would only be affected when trying to change a tiling or create a new one. (This is not to say that it's necessarily a good idea to make it impossible to achieve the current behaviour, just that if we cannot reconcile the two, there is some room for change.)
 +
 
 +
Note that it would be possible to emulate Inkscape's current behaviour through interpolation of transforms, but only if we would allow "stacking" transforms. I'm not sure how this would have to be supported UI-wise though.
 
|}
 
|}
  
=== Break tiling ===
+
== Implementation ==
 +
 
 +
Proposed implementation steps:
 +
 
 +
=== 0. Very desirable: Guide management ===
 +
 
 +
See [https://blueprints.launchpad.net/inkscape/+spec/guides-improvement Existing blueprint]. Rather, what is needed here is not a full guide management system, but rather how to "define" a guide, as the guides here have properties very different from "normal" objects.
 +
 
 +
=== I. Core feature: addition of an on-canvas base tile or render frame ===
  
By default, all tiles generated are clones of the original. 3 actions are available to the generated clones:
+
Jasper explains where the tiling code is located:
* Unclump: all generated clones are unlinked from the original. Subsequent transformations to the original no longer apply.
+
* Combine: Union ('Ctrl' + '+') is applied to the object and all its generated tiles (note: this option may not be useful...).
+
* Fuse paths: All end nodes located on guide points (see Guide Points for seamless tiling) are fused into a single node.
+
  
[[File:Break tiling.png]]
+
"All the code is in src/ui/dialog/clonetiler.cpp. The main function is CloneTiler::clonetiler_get_transform. This function essentially gets all info, as well as a row and column index."
[http://postimage.org/image/cdbx4oumh/ Behaviors for breaking tilings]
+
  
=== Guide alignment ===
+
As a first step, the programmer could program a "base tile" or "render frame" object as a separate file, that can be tested independently from the tiling code. This object:
 +
* Provides a different base tile shape depending on the chosen transformation type
 +
* Allows to visualize extra rows and columns on-canvas (not necessary in a first step, but quite desirable). Unless the user wants to tweak the tiling code itself, this step currently does not allow adding or removing individual tiles
 +
* Creates a set of coordinates to be used by the existing tiling mechanism
 +
* The tool icon and toolbar can be created from the start for testing or added later
  
* See also [https://blueprints.launchpad.net/inkscape/+spec/transformation-anchors Transformation anchor].
+
Testing would basically be to ensure that the on-canvas behaviour is consistent with what the user expects, and the output values are correct.
* Rather than serve as transformation anchors though, the guides get aligned to the corresponding corner (they're just to make alignment faster).
+
* However, although the guide gets aligned after a command, it can still be freely moved and transformed.
+
* Why no starting angle for Radial tiles? Well, save yourself a bit of trouble and make the starting pattern vertical.
+
  
=== Guide lock ===
+
Once this object works as expected, it can then be "connected" to the tiling mechanism by calling it up and sending it the correct values. Basically, the tiling code itself would not need too many adjustments at this phase.
  
* '''Guide locked to object''': the guide moves and scales with the object. For example, if a vase is made by applying a symmetry to half a vase, moving the original will also move the other half, so the whole vase is moved. In the same way, scaling a tile scales its guide. If an on-canvas axis or node was chosen to apply a transformation, a copy of the resulting two axis are created and move with the object.
+
[[File:Tiling Tool Step1.png|UI Proposal for first step of tiling tool implementation]]
* '''Unlocked guide''': the guide is absolute, so if the original gets moved, the copy will also be re-positioned according to the original guide position.
+
<br clear="all"/>
  
[http://postimage.org/image/fzmseg7bd/ Guide locking behavior]
+
This is basically the minimum interface that would allow users to make basic tiling without opening the current tiling dialogue. Sequence:
 +
* Clicking the + button "adds" a render frame or just render tile (if the programmer hasn't programmed the ability to visualize extra rows and columns yet) of the chosen type.
 +
* Choose the pattern to tile and the guide
 +
* Click "create"
  
=== Guide visibility ===
+
=== II. More features to the render frame ===
 +
 +
These are features that can be added to the render frame object without changing the tiling code too much.
 +
 +
''' 1. Tiling handles '''
 +
 +
# Handles are added to the base tiles, making it possible to switch from one tiling to another.
 +
# Users can be now offered to create a "Wallpaper" tile by default. Other transformation types are accessed via a pop-up when choosing "others." Previews are moved to this pop-up. Since the simple rectangle is the most commonly used tile shape, this default should be acceptable (and less confusing than "P1").
  
Guide visibility can be toggled on and off, so the user can edit the original object with other tools with the guide is still visible.
+
A few notes:
 +
* Changing symmetries should be the priority.
 +
* Eventually controls for angles could be added too, though this is lower priority, as not many users absolutely need to change from one tile shape to another.  
  
 +
''' 2. On-canvas dynamics editing '''
 +
 +
This converts on-canvas cues to percentage values that are then fed to the tiling code.
 +
Under discussion: Visual representation of the mechanism?
  
 +
''' 3. Guide points? '''
 +
 +
The programmer must:
 +
# Define/create guide points. This object can be snapped to objects and guides.
 +
# Program it so that iterations of it appear and are rendered correctly in each tile of the render frame according to the chosen transformation mode. If the transformation type is changed, they must also update automatically.
 +
# Additional feature: Ctrl-drag to create a segment from the point: this helps make transformations in each tile more obvious, and helps for handle-snapping.
  
== Guide editing ==
+
''' 4. Radial tiling cheat? '''
  
=== Guide transformations ===
+
A "radial tiling" guide form may be created on top of the existing mechanism. It's basically a P1 operation made to output radial tiling results. The render frame shsape allows users to more easily visualize radial tiling on-canvas. Any on-canvas dynamics manipulations also converts these values into settings appropriate for a "rows and columns" transformation.
  
Available transformations depend on the guide type:
+
By building this on top of the existing tiling mechanism, the programmer removes the need to create a dynamics system specific to radial tiling. On the down side, a user who wants to input values manually will have to deal with the rows and columns settings, which in this case would be less intuitive than "angular and radial" settings.
* All guides save symmetry axes can be resized. All guides can be rotated. Toggling occurs by clicking again as with the Transform tool.
+
* The angle for the angle tool for radial clones can be edited on canvas, like for the Circle tool.
+
* Skew is available for some tiling options using parallelogram guides.
+
* Input of numerical values could be available by double clicking a guide corner?
+
  
[http://postimage.org/image/qxy1wmvwp/ Guide editing options]
+
=== III. More tiling features ===
  
=== Guide points for seamless tiling ====
+
'''  1. Fuse mode '''
  
* Double-clicking on the side of a guide creates a guide point for seamless tiling. Copies of this guide point are automatically created at the relevant location on all concerned sides of the guide.
+
As noted, this is a cut + fuse operation. The programmer needs to implement the following features:
* These points can be moved around. All the other copies move as well.
+
# Boolean operations (specifically "cut") on groups
* Shift-drag on a guide point creates an angle guide, so users can better create smooth transitions.
+
# This also means fixing the cut operation, which is currently rather buggy...  
* '''When "Fuse paths" is applied, all end points snapped to guide points are fused, forming a single continuous path.'''
+
# The guides must be extended, and for each wallpaper group, the ways to "cut" the tiles must be defined
 +
# The programmer must then find the way to define the zone to be delete
 +
# "Fuse" uses the existing group node join operation however
 +
Alternatively, the programmer can make Inkscape render a shape over the tile and perform a union operation, but one that leaves resulting nodes instead of joining them.
 +
 +
** [https://bugs.launchpad.net/inkscape/+bug/166302 Bug #166302: Cut Path looses some segments ]
 +
** [https://bugs.launchpad.net/inkscape/+bug/171379 Bug #171379: Boolean Operations on Groups ]
 +
** [https://bugs.launchpad.net/inkscape/+bug/701819 Bug #701819: Copy/Cut a Part of a Grouped Object ] (scenario of above)
 +
** [https://bugs.launchpad.net/inkscape/+bug/408551 Bug #408551: Cut Path with a grouped object does nothing ]
  
[http://postimage.org/image/ae0dae6mh/ Guide points for seamless tiles]
+
This feature requires adding two additional phases to the tiling code:
 +
* A cut operation: the programmer must find a way to define which way the base tile is to be cut
 +
* Fuse operation at the very end
  
What's more, ctrl-clicking on a guide point creates a new guide point that forms a guide point pair with the first one.
+
''' 2. Allow adding and removing individual tiles to the render frame '''
* '''When "Fuse paths" is applied, the segments between these two nodes gets deleted, and the resulting open nodes are joined with the corresponding nodes on the next tile.'''
+
* Separating guide points and guide point pairs is necessary because Inkscape does a bad job of recognizing two separate lines as defining the borders of a single object.
+
  
[http://postimage.org/image/kqmnwh05l/ Guide pairs for seamless tiles]
+
The biggest work here is reworking the tiling code so that not all tiles are rendered. Combining this and "fuse path" will take some work.
  
== Advanced transformation options ==
+
''' 3. Interpolation gradients? '''
  
The "Dynamics" button opens up a separate dialogue with transformation options corresponding to the current tiling interface. Major differences are:
+
As Jasper noted, this may require a whole rework of the tiling mechanism.
* Vertical listing
+
* Checkbox next to every transformation type, so users can easily remove all of them while retaining some values.
+
* Radial Clones use Polar coordinates.
+
* Clones along Path use orthogonal coordinates (normal and orthogonal).
+
* Users can save and use presets. This includes a "No dynamics" option.
+
Originally I pondered whether presets should be located at the "Advanced" level or at the top level (i.e. presets include tiling type). But I reason that dynamics such as fading and color hues for example work about the same no matter what tiling type you're using.
+
  
[http://postimage.org/image/qxszzipl5/ Advanced options for tilings]
+
=== IV. Line tiling ===
  
== To-do ==
+
Line tiling requires a whole new mechanism combining dynamics and "pattern along path." A possible behaviour is:
 +
* The programmer adapts the tiling code to the Frieze groups
 +
* Clones are first generated in a straight line according to number and size inputs from the target path
 +
* They are then set along the target path using "pattern along path" mechanism.
  
Think up an interface for Clone Along Path that allows a more advanced version of Pattern Along Path thanks to using guide points on a basic tile. The main issue is that all the tiles, including the original, gets deformed along the path, so editing the base tile must be done separately.
+
[[Category:Proposals]]

Latest revision as of 07:54, 9 April 2012

Tiling tool

The current tiling interface is hard to use. The current interface attempts to make the process more user friendly through the use of a tool that creates a "render frame", which consists of two parts:

  • A base tile, where the pattern is supposed to be
  • A more general render frame, showing the location of the output
  • Both can be edited on-canvas

The tiling process is simply:

  1. Create a frame
  2. Select a pattern and a frame
  3. Click "Render" from the tiling tool
  • By default the frame becomes invisible after a render, and becomes "implied" in the generated output (a bit like clipping?).
  • Undoing the render makes the frame appear again.
  • The user can choose to drop a copy of the frame after a render for re-use however, or make a copy before applying.
Type Description
Wallpaper tiling Allows users to use the 17 wallpaper types.
Radial tiling
  • This is for radial designs, and allows both angular clones and radial clones.
  • For angular clones, users can choose between simple rotation or symmetry + rotation. (thus covering the Rosetta patterns as well)
  • For radial clones, users can choose between same direction and alternating directions.
Path tiling
  • Clones are generated along a path. This can be used to create a string of decorations, for repeating frills, for page borders etc.
  • Users can choose from all 7 Frieze groups.

UI Proposal for tiling tool

Transformation images for wallpaper groups

Render modes

There are two modes:

  • Create clones: This is the current rendering mode
  • Fuse: This mode first cuts excess for "inner" sides, then performs a "fuse" operation on the whole output.

Explanation of "Fuse" feature for tiling proposal

More examples of the possible outputs for the “Fuse Cut” mode

Render frame

The render frame is made up of:

  • A central tile, which defines the location of the pattern to copy
  • A more general render grid

UI Proposal for the Render frame of the Tiling tool proposal

On-canvas transformation handles

UI proposal for on-canvas handles for the tiling tool proposal

Guide points

UI proposal for guide points feature for Tiling Tool

Guide points are there to serve as reference point when creating tile designs.

  • When you add a guide point, "counterparts" are generated in all the other tiles
  • Ctrl-drag to drag out a segment.
  • The idea is that users can snap guide points along tile edges, snap a node of the pattern to that guide and snap the node handle to the end of the guide segment, then repeat with the guide point's counterparts. This should help easily create seamless transitions.

Option for dynamics Symmetry around base tile?

Proposal: option for all dynamics to be rendered in a symmetry around the base tile. This proposal is because users may want tiles to fade around a central tile. Rendering the frame in just one direction is easy, but achieving the symmetry otherwise is not.

The main difficulty is that the current dynamics mechanism is linear, so adjustments would be needed.

Proposal for dynamics to occur in a symmetry around the base tile for the tiling tool

On-canvas dynamics editing

Currently the two following approaches to on-canvas dynamics editing have been considered:

  1. Edit a tile of the render frame (rotate and resize for example), all other tiles in the render frame are updated dynamically to give you an idea of the result.
    • Pros: high preview value, as the outline of the tiles by themselves should give an idea as to the output of the whole tiling.
    • Cons: forcing live update of tiles may be slow, and big displacements of tiles are distracting from the editing process. Worse if jitters are also visualized on-canvas.
  2. Edit only one or two "reference" tiles. None of the other tiles change. Inkscape deduces transformation values from there and converts them into values for the existing tiling mechanism.
    • Pros: less taxing on the interface.
    • Cons: Less preview value.

Tom Lechner made a possible mock-up for the second option: Mock-up for on-canvas tile dynamics editing

It could be possible to combine the best of both worlds with a "Dynamics preview" mode (so it's a preview of the dynamics, not of the pattern getting tiled):

  • When preview mode is on, Inkscape generates a preview of the render frame's tiles with dynamics applied, including jitters.
  • Editing is not allowed. You have to exit the preview mode to make other adjustments.
  • The idea is that some complex tilings will probably take a long time to render. This preview mode gives a quick idea about the outcome without having to do a full render, then undo, adjust and re-render again.

Preview mode for dynamics for the Tiling Tool proposal

Radial tiling

In theory, radial tiling could use the same mechanism as rows and columns tiling, by converting all input into X, Y input. Although users can also use rows and columns tiling to achieve radial tiling, doing so would not be very intuitive.

UI proposal for radial tiling in the tiling tool

Line tiling

Implementing line tiling would be more complicated that implementing radial tiling, because it is an extension of the Pattern Along Path function rather than of the existing tiled clones mechanism. So, the programer would have to figure out a way to combine Pattern Along Path and the dynamics for Tiled Clones, all the while implementing the proper render guide. If he achieves it though, it'd be an amazingly powerful and versatile tool for designers of all kinds.

Line tiling actually comes in two sets of guides:

  • A pattern guide.
  • A target guide. This target guide appears over the target path, which has to be copied first to the clipboard.

The pattern guide can actually be edited independently of a target path, but unless a target path is copied to the clipboard, the user cannot render the line tiling. So, the user can first adjust the pattern design and tiling properties, then copy a path, adjust and apply.

UI proposal for line tiling in the tiling tool

Tile stacking

You can stack different tilings!

Explanation of tile stacking feature for my tiling proposal

Inkscape will likely have an Effects stacking mechanism in the future. Whatever it is, tiling would also fit right into it.

Line patterns

And why not "line patterns" while we're at it?

UI proposal for line pattern choosing

UI design status

This section is a summary of how ready the UI proposal for the various features are (as well as comments about coding):

General concept and tiling methods:

Feature Status
General concept Valerie: The current interface is the result of exploring several very different concepts with inputs and criticism by a number of people. The "On-canvas editable central tile + render frame" concept is currently the first of these concepts to have encountered no major objections as to its usability, so it should be safe to consider this an acceptable general direction unless a better proposal comes along.
Wallpaper tiling Valerie: The general proposal (base tile, handles + render frame) doesn't seem to generate many objections. The exact form of the handles and the details about manipulation could still be refined.
Radial tiling Valerie: Not much input yet.
Line tiling Valerie: Not much input yet. There should be, as this is a potentially very powerful feature for designers, though also hard to implement.

Specific features (all tiling methods)

Feature Status
Fuse mode Valerie: General input seems to be that this is a "good idea."
Guide points Valerie: General input seems to be that this is a "good idea."
On-canvas handling of dynamics Valerie: Concensus is that on-canvas manipulation of dynamics is very desirable. However, the exact form is still up to debate. Tom Lechner has a proposal that will allow to visualize most elements, but more work is needed to establish a mechanism for visualizing and controlling jitter as well.
Multi-Stop Interpolation Gradient (multi-stop dynamics) Valerie: Such a mechanism would require reworking the entire tiling mechanism. The only bright side is that Inkscape doesn't store any tiling information, so changing the mechanism won't break backwards compatibility. See Jasper's detailed comment in "Implementation."
Symmetrical dynamics output around base tile Valerie: Looking at Jasper's explanation below, symmetrical dynamics around a central tile basically aren't supported by the current mechanism.
Tile stacking and line pattern management Valerie: At this point both are just suggestions, as Inkscape has neither the mechanisms in place nor an UI.

Implementation comments

Feature Comments
Multi-Stop Interpolation Gradient Jasper (mail from mailing list): All the code is in src/ui/dialog/clonetiler.cpp. The main function is CloneTiler::clonetiler_get_transform. This function essentially gets all info, as well as a row and column index. It then computes all the transforms required for that position and combines them. As far as I can tell it combines them in such a way that first a scaling is applied, then a rotation and finally a translation. If you select a different symmetry group then the translation can become a more complicated transform.

The scheme we talked about earlier that would interpolate transforms is not necessarily compatible. This is because in the latter the case the entire transform would be interpolated, while what Inkscape does is essentially interpolating per kind of transform. That this is not the same can be seen by realizing that rotate(50)translate(1)rotate(50)translate(1) is not the same as rotate(100)translate(2). The former is more or less what we talked about (or at least what I had in mind during that discussion), the latter is what Inkscape does.

However, Inkscape currently seems to store almost nothing about the tiling in the file. So it would be relatively benign to change behaviour. Existing files would not be affected in any way, users would only be affected when trying to change a tiling or create a new one. (This is not to say that it's necessarily a good idea to make it impossible to achieve the current behaviour, just that if we cannot reconcile the two, there is some room for change.)

Note that it would be possible to emulate Inkscape's current behaviour through interpolation of transforms, but only if we would allow "stacking" transforms. I'm not sure how this would have to be supported UI-wise though.

Implementation

Proposed implementation steps:

0. Very desirable: Guide management

See Existing blueprint. Rather, what is needed here is not a full guide management system, but rather how to "define" a guide, as the guides here have properties very different from "normal" objects.

I. Core feature: addition of an on-canvas base tile or render frame

Jasper explains where the tiling code is located:

"All the code is in src/ui/dialog/clonetiler.cpp. The main function is CloneTiler::clonetiler_get_transform. This function essentially gets all info, as well as a row and column index."

As a first step, the programmer could program a "base tile" or "render frame" object as a separate file, that can be tested independently from the tiling code. This object:

  • Provides a different base tile shape depending on the chosen transformation type
  • Allows to visualize extra rows and columns on-canvas (not necessary in a first step, but quite desirable). Unless the user wants to tweak the tiling code itself, this step currently does not allow adding or removing individual tiles
  • Creates a set of coordinates to be used by the existing tiling mechanism
  • The tool icon and toolbar can be created from the start for testing or added later

Testing would basically be to ensure that the on-canvas behaviour is consistent with what the user expects, and the output values are correct.

Once this object works as expected, it can then be "connected" to the tiling mechanism by calling it up and sending it the correct values. Basically, the tiling code itself would not need too many adjustments at this phase.

UI Proposal for first step of tiling tool implementation

This is basically the minimum interface that would allow users to make basic tiling without opening the current tiling dialogue. Sequence:

  • Clicking the + button "adds" a render frame or just render tile (if the programmer hasn't programmed the ability to visualize extra rows and columns yet) of the chosen type.
  • Choose the pattern to tile and the guide
  • Click "create"

II. More features to the render frame

These are features that can be added to the render frame object without changing the tiling code too much.

1. Tiling handles

  1. Handles are added to the base tiles, making it possible to switch from one tiling to another.
  2. Users can be now offered to create a "Wallpaper" tile by default. Other transformation types are accessed via a pop-up when choosing "others." Previews are moved to this pop-up. Since the simple rectangle is the most commonly used tile shape, this default should be acceptable (and less confusing than "P1").

A few notes:

  • Changing symmetries should be the priority.
  • Eventually controls for angles could be added too, though this is lower priority, as not many users absolutely need to change from one tile shape to another.

2. On-canvas dynamics editing

This converts on-canvas cues to percentage values that are then fed to the tiling code. Under discussion: Visual representation of the mechanism?

3. Guide points?

The programmer must:

  1. Define/create guide points. This object can be snapped to objects and guides.
  2. Program it so that iterations of it appear and are rendered correctly in each tile of the render frame according to the chosen transformation mode. If the transformation type is changed, they must also update automatically.
  3. Additional feature: Ctrl-drag to create a segment from the point: this helps make transformations in each tile more obvious, and helps for handle-snapping.

4. Radial tiling cheat?

A "radial tiling" guide form may be created on top of the existing mechanism. It's basically a P1 operation made to output radial tiling results. The render frame shsape allows users to more easily visualize radial tiling on-canvas. Any on-canvas dynamics manipulations also converts these values into settings appropriate for a "rows and columns" transformation.

By building this on top of the existing tiling mechanism, the programmer removes the need to create a dynamics system specific to radial tiling. On the down side, a user who wants to input values manually will have to deal with the rows and columns settings, which in this case would be less intuitive than "angular and radial" settings.

III. More tiling features

1. Fuse mode

As noted, this is a cut + fuse operation. The programmer needs to implement the following features:

  1. Boolean operations (specifically "cut") on groups
  2. This also means fixing the cut operation, which is currently rather buggy...
  3. The guides must be extended, and for each wallpaper group, the ways to "cut" the tiles must be defined
  4. The programmer must then find the way to define the zone to be delete
  5. "Fuse" uses the existing group node join operation however

Alternatively, the programmer can make Inkscape render a shape over the tile and perform a union operation, but one that leaves resulting nodes instead of joining them.

This feature requires adding two additional phases to the tiling code:

  • A cut operation: the programmer must find a way to define which way the base tile is to be cut
  • Fuse operation at the very end

2. Allow adding and removing individual tiles to the render frame

The biggest work here is reworking the tiling code so that not all tiles are rendered. Combining this and "fuse path" will take some work.

3. Interpolation gradients?

As Jasper noted, this may require a whole rework of the tiling mechanism.

IV. Line tiling

Line tiling requires a whole new mechanism combining dynamics and "pattern along path." A possible behaviour is:

  • The programmer adapts the tiling code to the Frieze groups
  • Clones are first generated in a straight line according to number and size inputs from the target path
  • They are then set along the target path using "pattern along path" mechanism.