gstreamer/ext/gl/gstglutils.c
Matthew Waters 16cba63d43 gl/utils: fixup matrix math again for column major
e4bf9ed8f0 was not quite right and changed
the wrong thing. Intead we needed to change the multiplication order
and should have kept the previous to/from matrices as is done in this
patch.
2018-07-10 20:13:22 +10:00

178 lines
4.5 KiB
C

/*
* GStreamer
* Copyright (C) 2016 Matthew Waters <matthew@centricular.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <gst/gl/gstglfuncs.h>
#include "gstglutils.h"
struct _compile_shader
{
GstGLShader **shader;
const gchar *vertex_src;
const gchar *fragment_src;
};
static void
_compile_shader (GstGLContext * context, struct _compile_shader *data)
{
GstGLShader *shader;
GstGLSLStage *vert, *frag;
GError *error = NULL;
shader = gst_gl_shader_new (context);
if (data->vertex_src) {
vert = gst_glsl_stage_new_with_string (context, GL_VERTEX_SHADER,
GST_GLSL_VERSION_NONE,
GST_GLSL_PROFILE_ES | GST_GLSL_PROFILE_COMPATIBILITY, data->vertex_src);
if (!gst_glsl_stage_compile (vert, &error)) {
GST_ERROR_OBJECT (vert, "%s", error->message);
gst_object_unref (vert);
gst_object_unref (shader);
return;
}
if (!gst_gl_shader_attach (shader, vert)) {
gst_object_unref (shader);
return;
}
}
if (data->fragment_src) {
frag = gst_glsl_stage_new_with_string (context, GL_FRAGMENT_SHADER,
GST_GLSL_VERSION_NONE,
GST_GLSL_PROFILE_ES | GST_GLSL_PROFILE_COMPATIBILITY,
data->fragment_src);
if (!gst_glsl_stage_compile (frag, &error)) {
GST_ERROR_OBJECT (frag, "%s", error->message);
gst_object_unref (frag);
gst_object_unref (shader);
return;
}
if (!gst_gl_shader_attach (shader, frag)) {
gst_object_unref (shader);
return;
}
}
if (!gst_gl_shader_link (shader, &error)) {
GST_ERROR_OBJECT (shader, "%s", error->message);
g_error_free (error);
error = NULL;
gst_gl_context_clear_shader (context);
gst_object_unref (shader);
return;
}
*data->shader = shader;
}
/* Called by glfilter */
gboolean
gst_gl_context_gen_shader (GstGLContext * context, const gchar * vert_src,
const gchar * frag_src, GstGLShader ** shader)
{
struct _compile_shader data;
g_return_val_if_fail (frag_src != NULL || vert_src != NULL, FALSE);
g_return_val_if_fail (shader != NULL, FALSE);
data.shader = shader;
data.vertex_src = vert_src;
data.fragment_src = frag_src;
gst_gl_context_thread_add (context, (GstGLContextThreadFunc) _compile_shader,
&data);
return *shader != NULL;
}
static const gfloat identity_matrix[] = {
1.0, 0.0, 0.0, 0.0,
0.0, 1.0, 0.0, 0.0,
0.0, 0.0, 1.0, 0.0,
0.0, 0.0, 0.0, 1.0,
};
static const gfloat from_ndc_matrix[] = {
0.5, 0.0, 0.0, 0.0,
0.0, 0.5, 0.0, 0.0,
0.0, 0.0, 0.5, 0.0,
0.5, 0.5, 0.5, 1.0,
};
static const gfloat to_ndc_matrix[] = {
2.0, 0.0, 0.0, 0.0,
0.0, 2.0, 0.0, 0.0,
0.0, 0.0, 2.0, 0.0,
-1.0, -1.0, -1.0, 1.0,
};
void
gst_gl_multiply_matrix4 (const gfloat * a, const gfloat * b, gfloat * result)
{
int i, j, k;
gfloat tmp[16] = { 0.0f };
if (!a || !b || !result)
return;
for (i = 0; i < 4; i++) { /* column */
for (j = 0; j < 4; j++) { /* row */
for (k = 0; k < 4; k++) {
tmp[j + (i * 4)] += a[k + (i * 4)] * b[j + (k * 4)];
}
}
}
for (i = 0; i < 16; i++)
result[i] = tmp[i];
}
void gst_gl_get_affine_transformation_meta_as_ndc_ext
(GstVideoAffineTransformationMeta * meta, gfloat * matrix)
{
if (!meta) {
int i;
for (i = 0; i < 16; i++) {
matrix[i] = identity_matrix[i];
}
} else {
float tmp[16];
gst_gl_multiply_matrix4 (from_ndc_matrix, meta->matrix, tmp);
gst_gl_multiply_matrix4 (tmp, to_ndc_matrix, matrix);
}
}
void gst_gl_set_affine_transformation_meta_from_ndc_ext
(GstVideoAffineTransformationMeta * meta, const gfloat * matrix)
{
float tmp[16];
g_return_if_fail (meta != NULL);
gst_gl_multiply_matrix4 (to_ndc_matrix, matrix, tmp);
gst_gl_multiply_matrix4 (tmp, from_ndc_matrix, meta->matrix);
}