The result of applying a perspective-transform to a Bezier curve is
only an approximation. When the curve is highly nonlinear, the
result may diverge significantly from the real transformed curve.
Subdivide the curve as necessary in gimp_transform_bezier_coords()
to counter that. Adjust gimp_bezier_stroke_transform()
accordingly.
... which transforms a single cubic Bezier segment, performing
clipping by the near plane, to avoid erroneously transforming parts
of the curve behind the camera.
... which is the same as gimp_transform_polygon(), but using
GimpCoords for the vertices, instead of GimpVector2.
Specify when the input and output arguments may alias, in the
description of gimp_transform_polygon().
When the resulting matrix transforms all input points behind the
camera, negate the matrix, instead of failing, which results in a
matrix that transforms the input points to the corresponding points
in front of the camera. This avoids rejecting certain valid
transforms as invalid, in the generic transform tools (unified,
perspective, and handle transform).
Make the number of input and output points explicit in the
function's signature, and add comments.
gimp_transform_polygon() transforms an (open or closed) polygon by
a GimpMatrix3, performing clipping to the near plane, to avoid
erroneously transforming points behind the camera.
Derive GimpUnifiedTransformTool, GimpPerspectiveTool, and
GimpHandleTransformTool from GimpGenericTransformTool, eliminating
their common logic.
Remove gimp_transform_matrix_handles(), which is no longer used.
A subclass of GimpTransformTool, to be used as a base class for
transform tools that calculate their matrix based on 4 pairs of
input/output points, and that display the transform matrix as their
GUI (this includes the unified, perspective, and handle transform
tools; the next commit ports them over to
GimpGenericTransformTool).
When the resulting matrix of the input/output mapping sends any of
the output points to, or past, infinity, GimpGenericTransformTool
sets GimpTransformTool::transform_valid to FALSE, and displays an
appropriate message in the tool GUI, instead of showing the matrix.
Instead, add utility functions that calculate the centers for rotate
and flip and use them where we used to pass "auto_center". This looks
pretty much poinless, but a commit will follow that makes it look
better...
2009-01-17 Michael Natterer <mitch@gimp.org>
* all files with a GPL header and all COPYING files:
Change licence to GPLv3 (and to LGPLv3 for libgimp).
Cleaned up some copyright headers and regenerated the parsers in
the ImageMap plugin.
svn path=/trunk/; revision=27913
2004-10-27 Michael Natterer <mitch@gimp.org>
* app/core/gimp-transform-utils.[ch]. switch from x1,y1,x2,y2
bounding boxes to x,y,width,height ones. Added
gimp_transform_matrix_flip_free(). Renamed some parameters to be
consistent with others. Some internal cleanup.
* app/tools/gimpperspectivetool.c
* app/tools/gimpscaletool.c
* app/tools/gimpsheartool.c
* tools/pdbgen/pdb/drawable_transform.pdb
* tools/pdbgen/pdb/transform_tools.pdb: changed accordingly.
* tools/pdbgen/pdb/drawable_transform.pdb
* tools/pdbgen/pdb/transform_tools.pdb: guard all transform
wrappers with if(gimp_drawable_mask_intersect(...)), also the
ones which don't need the returned bounding box.
* tools/pdbgen/pdb/drawable_transform.pdb: renamed some parameters
and added gimp_drawable_transform_matrix() which takes the 9
coefficients of a 3x3 matrix for ultimate flexibility ;)
* app/pdb/drawable_transform_cmds.c
* app/pdb/internal_procs.c
* app/pdb/transform_tools_cmds.c
* libgimp/gimpdrawabletransform_pdb.[ch]: regenerated.
2003-09-15 Sven Neumann <sven@gimp.org>
* app/core/gimpdrawable-transform-utils.[ch]: removed...
* app/core/gimp-transform-utils.[ch]: ...and added under new names
because these functions are not at all related to GimpDrawable.
Changed the function names accordingly.
* app/tools/gimpperspectivetool.c
* app/tools/gimprotatetool.c
* app/tools/gimpscaletool.c
* app/tools/gimpsheartool.c
* app/vectors/gimpstroke.c
* app/vectors/gimpvectors.c
* tools/pdbgen/pdb/transform_tools.pdb: changed accordingly.
* app/pdb/transform_tools_cmds.c: regenerated.
2003-09-11 Sven Neumann <sven@gimp.org>
* app/core/gimpdrawable-transform-utils.[ch]: added new function
gimp_drawable_transform_matrix_flip().
* app/vectors/gimpstroke.[ch]
* app/vectors/gimpvectors.c: don't push the complex GimpItem
transformation API down to GimpStroke. Instead setup the matrices
in GimpVectors and use a simpler API for GimpStroke.
* app/vectors/gimpvectors-import.c: changed accordingly.
* app/vectors/gimpvectors-export.c: close the <path> element.
2002-02-19 Michael Natterer <mitch@gimp.org>
Fixed#10466 (disappearing pixels when rotating by 90 deg):
* app/core/gimpdrawable-transform.c: when transforming backwards
to find the destination line's sub-pixel source coordinates, we
need to transform the pixels _center_, not it's upper left corner.
* app/core/gimpdrawable-transform-utils.[ch]: added
gimp_drawable_transform_matrix_rotate_center() which takes double
center coordinates instead of an integer pixel bounding box.
* app/tools/gimptransformtool.[ch]: use double instead of int for
all coordinates except the original bounding box.
* app/tools/gimprotatetool.c: use double whenever touching the
"center" value, so it can be sub-pixel positioned.
2001-11-19 Michael Natterer <mitch@gimp.org>
* app/display/gimpdisplay-foreach.c: forgot to commit last time.
Transform stuff cleanup:
* app/core/Makefile.am
* app/core/core-types.h
* app/core/gimpdrawable-transform.[ch]: new files implementing
the actual transform functions cut from tools/gimptransformtool.*.
* app/core/gimpdrawable-transform-utils.[ch]: new files implementing
transform matrix assembly utility functions.
* app/tools/gimptransformtool.[ch]: removed the stuff here. cleanup.
* app/tools/transform_options.[ch]: removed all stuff which does
not belong here, e.g. the transform_tool_* functions and the
global "transform_options" variable. Works like all other tool
options now.
* app/tools/gimpfliptool.[ch]
* app/tools/gimpperspectivetool.[ch]
* app/tools/gimprotatetool.[ch]
* app/tools/gimpscaletool.[ch]
* app/tools/gimpsheartool.[ch]: massive code removal because
we can use core/gimpdrawable-fransform* functions now. cleanup.
* tools/pdbgen/Makefile.am
* tools/pdbgen/groups.pl: added new PDB group "transform_tools".
* tools/pdbgen/pdb/tools.pdb: removed the transform stuff here...
* tools/pdbgen/pdb/transform_tools.pdb: and added *much*
simplified versions which use the new core/gimpdrawable-transform*
utilities.
* app/pdb/Makefile.am
* app/pdb/transform_tools_cmds.c: new file.
* app/pdb/internal_procs.c
* app/pdb/tools_cmds.c: regenerated.
* libgimp/Makefile.am
* libgimp/gimp_pdb.h
* libgimp/gimptransformtools_pdb.[ch]: new files.
* libgimp/gimptools_pdb.[ch]: regenerated.
Michael Natterer