mutter/cogl/cogl-spans.c
Robert Bragg a0441778ad This re-licenses Cogl 1.18 under the MIT license
Since the Cogl 1.18 branch is actively maintained in parallel with the
master branch; this is a counter part to commit 1b83ef938fc16b which
re-licensed the master branch to use the MIT license.

This re-licensing is a follow up to the proposal that was sent to the
Cogl mailing list:
http://lists.freedesktop.org/archives/cogl/2013-December/001465.html

Note: there was a copyright assignment policy in place for Clutter (and
therefore Cogl which was part of Clutter at the time) until the 11th of
June 2010 and so we only checked the details after that point (commit
0bbf50f905)

For each file, authors were identified via this Git command:
$ git blame -p -C -C -C20 -M -M10  0bbf50f905..HEAD

We received blanket approvals for re-licensing all Red Hat and Collabora
contributions which reduced how many people needed to be contacted
individually:
- http://lists.freedesktop.org/archives/cogl/2013-December/001470.html
- http://lists.freedesktop.org/archives/cogl/2014-January/001536.html

Individual approval requests were sent to all the other identified authors
who all confirmed the re-license on the Cogl mailinglist:
http://lists.freedesktop.org/archives/cogl/2014-January

As well as updating the copyright header in all sources files, the
COPYING file has been updated to reflect the license change and also
document the other licenses used in Cogl such as the SGI Free Software
License B, version 2.0 and the 3-clause BSD license.

This patch was not simply cherry-picked from master; but the same
methodology was used to check the source files.
2014-02-22 02:02:53 +00:00

184 lines
5.2 KiB
C

/*
* Cogl
*
* A Low Level GPU Graphics and Utilities API
*
* Copyright (C) 2007,2008,2009 Intel Corporation.
*
* Permission is hereby granted, free of charge, to any person
* obtaining a copy of this software and associated documentation
* files (the "Software"), to deal in the Software without
* restriction, including without limitation the rights to use, copy,
* modify, merge, publish, distribute, sublicense, and/or sell copies
* of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*
*
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "math.h"
#include "cogl-util.h"
#include "cogl-spans.h"
void
_cogl_span_iter_update (CoglSpanIter *iter)
{
/* Pick current span */
iter->span = &iter->spans[iter->index];
/* Offset next position by span size */
iter->next_pos = iter->pos + iter->span->size - iter->span->waste;
/* Check if span intersects the area to cover */
if (iter->next_pos <= iter->cover_start ||
iter->pos >= iter->cover_end)
{
/* Intersection undefined */
iter->intersects = FALSE;
return;
}
iter->intersects = TRUE;
/* Clip start position to coverage area */
if (iter->pos < iter->cover_start)
iter->intersect_start = iter->cover_start;
else
iter->intersect_start = iter->pos;
/* Clip end position to coverage area */
if (iter->next_pos > iter->cover_end)
iter->intersect_end = iter->cover_end;
else
iter->intersect_end = iter->next_pos;
}
void
_cogl_span_iter_begin (CoglSpanIter *iter,
const CoglSpan *spans,
int n_spans,
float normalize_factor,
float cover_start,
float cover_end,
CoglPipelineWrapMode wrap_mode)
{
/* XXX: If CLAMP_TO_EDGE needs to be emulated then it needs to be
* done at a higher level than here... */
_COGL_RETURN_IF_FAIL (wrap_mode == COGL_PIPELINE_WRAP_MODE_REPEAT ||
wrap_mode == COGL_PIPELINE_WRAP_MODE_MIRRORED_REPEAT);
iter->span = NULL;
iter->spans = spans;
iter->n_spans = n_spans;
/* We always iterate in a positive direction from the origin. If
* iter->flipped == TRUE that means whoever is using this API should
* interpreted the current span as extending in the opposite direction. I.e.
* it extends to the left if iterating the X axis, or up if the Y axis. */
if (cover_start > cover_end)
{
float tmp = cover_start;
cover_start = cover_end;
cover_end = tmp;
iter->flipped = TRUE;
}
else
iter->flipped = FALSE;
/* The texture spans cover the normalized texture coordinate space ranging
* from [0,1] but to help support repeating of sliced textures we allow
* iteration of any range so we need to relate the start of the range to the
* nearest point equivalent to 0.
*/
if (normalize_factor != 1.0)
{
float cover_start_normalized = cover_start / normalize_factor;
iter->origin = floorf (cover_start_normalized) * normalize_factor;
}
else
iter->origin = floorf (cover_start);
iter->wrap_mode = wrap_mode;
if (wrap_mode == COGL_PIPELINE_WRAP_MODE_REPEAT)
iter->index = 0;
else if (wrap_mode == COGL_PIPELINE_WRAP_MODE_MIRRORED_REPEAT)
{
if ((int)iter->origin % 2)
{
iter->index = iter->n_spans - 1;
iter->mirror_direction = -1;
iter->flipped = !iter->flipped;
}
else
{
iter->index = 0;
iter->mirror_direction = 1;
}
}
else
g_warn_if_reached ();
iter->cover_start = cover_start;
iter->cover_end = cover_end;
iter->pos = iter->origin;
/* Update intersection */
_cogl_span_iter_update (iter);
while (iter->next_pos <= iter->cover_start)
_cogl_span_iter_next (iter);
}
void
_cogl_span_iter_next (CoglSpanIter *iter)
{
/* Move current position */
iter->pos = iter->next_pos;
if (iter->wrap_mode == COGL_PIPELINE_WRAP_MODE_REPEAT)
iter->index = (iter->index + 1) % iter->n_spans;
else if (iter->wrap_mode == COGL_PIPELINE_WRAP_MODE_MIRRORED_REPEAT)
{
iter->index += iter->mirror_direction;
if (iter->index == iter->n_spans || iter->index == -1)
{
iter->mirror_direction = -iter->mirror_direction;
iter->index += iter->mirror_direction;
iter->flipped = !iter->flipped;
}
}
else
g_warn_if_reached ();
/* Update intersection */
_cogl_span_iter_update (iter);
}
CoglBool
_cogl_span_iter_end (CoglSpanIter *iter)
{
/* End reached when whole area covered */
return iter->pos >= iter->cover_end;
}