mutter/clutter/tests/interactive/test-cogl-offscreen.c
2016-04-12 20:04:26 +02:00

334 lines
9.3 KiB
C

#include <glib.h>
#include <gmodule.h>
#include <stdlib.h>
#include <clutter/clutter.h>
#include <cogl/cogl.h>
/* Coglbox declaration
*--------------------------------------------------*/
G_BEGIN_DECLS
#define TEST_TYPE_COGLBOX test_coglbox_get_type()
#define TEST_COGLBOX(obj) \
(G_TYPE_CHECK_INSTANCE_CAST ((obj), \
TEST_TYPE_COGLBOX, TestCoglboxClass))
#define TEST_COGLBOX_CLASS(klass) \
(G_TYPE_CHECK_CLASS_CAST ((klass), \
TEST_TYPE_COGLBOX, TestCoglboxClass))
#define TEST_IS_COGLBOX(obj) \
(G_TYPE_CHECK_INSTANCE_TYPE ((obj), \
TEST_TYPE_COGLBOX))
#define TEST_IS_COGLBOX_CLASS(klass) \
(G_TYPE_CHECK_CLASS_TYPE ((klass), \
TEST_TYPE_COGLBOX))
#define TEST_COGLBOX_GET_CLASS(obj) \
(G_TYPE_INSTANCE_GET_CLASS ((obj), \
TEST_TYPE_COGLBOX, TestCoglboxClass))
typedef struct _TestCoglbox TestCoglbox;
typedef struct _TestCoglboxClass TestCoglboxClass;
typedef struct _TestCoglboxPrivate TestCoglboxPrivate;
struct _TestCoglbox
{
ClutterActor parent;
/*< private >*/
TestCoglboxPrivate *priv;
};
struct _TestCoglboxClass
{
ClutterActorClass parent_class;
/* padding for future expansion */
void (*_test_coglbox1) (void);
void (*_test_coglbox2) (void);
void (*_test_coglbox3) (void);
void (*_test_coglbox4) (void);
};
static GType test_coglbox_get_type (void) G_GNUC_CONST;
G_END_DECLS
/* Coglbox private declaration
*--------------------------------------------------*/
G_DEFINE_TYPE (TestCoglbox, test_coglbox, CLUTTER_TYPE_ACTOR);
#define TEST_COGLBOX_GET_PRIVATE(obj) \
(G_TYPE_INSTANCE_GET_PRIVATE ((obj), TEST_TYPE_COGLBOX, TestCoglboxPrivate))
struct _TestCoglboxPrivate
{
CoglHandle texhand_id;
CoglHandle texture_id;
CoglHandle offscreen_id;
};
/* Coglbox implementation
*--------------------------------------------------*/
static void
test_coglbox_paint (ClutterActor *self)
{
TestCoglboxPrivate *priv = TEST_COGLBOX_GET_PRIVATE (self);
gfloat texcoords[4] = { 0, 0, 1, 1 };
CoglHandle material;
cogl_set_source_color4ub (0x66, 0x66, 0xdd, 0xff);
cogl_rectangle (0, 0, 400, 400);
cogl_set_source_texture (priv->texhand_id);
cogl_rectangle_with_texture_coords (0, 0,
400, 400,
0, 0,
6, 6);
cogl_push_framebuffer (priv->offscreen_id);
cogl_set_source_color4ub (0xff, 0, 0, 0xff);
cogl_rectangle (20, 20, 20 + 100, 20 + 100);
cogl_set_source_color4ub (0, 0xff, 0, 0xff);
cogl_rectangle (80, 80, 80 + 100, 80 + 100);
cogl_pop_framebuffer ();
material = cogl_material_new ();
cogl_material_set_color4ub (material, 0x88, 0x88, 0x88, 0x88);
cogl_material_set_layer (material, 0, priv->texture_id);
cogl_set_source (material);
cogl_rectangle_with_texture_coords (100, 100,
300, 300,
texcoords[0],
texcoords[1],
texcoords[2],
texcoords[3]);
}
static void
test_coglbox_finalize (GObject *object)
{
G_OBJECT_CLASS (test_coglbox_parent_class)->finalize (object);
}
static void
test_coglbox_dispose (GObject *object)
{
TestCoglboxPrivate *priv;
priv = TEST_COGLBOX_GET_PRIVATE (object);
cogl_handle_unref (priv->texture_id);
cogl_handle_unref (priv->offscreen_id);
G_OBJECT_CLASS (test_coglbox_parent_class)->dispose (object);
}
/* A newly created Cogl framebuffer will be initialized with a
* viewport covering the size of the viewport i.e. equavalent to:
*
* calling cogl_framebuffer_set_viewport (
* fb,
* 0, 0,
* cogl_framebuffer_get_viewport_width (fb),
* cogl_framebuffer_get_viewport_width (fb));
*
* The projection matrix will be an identity matrix.
*
* The modelview matrix will be an identity matrix, and this will
* create a coordinate system - like OpenGL - with the viewport
* being mapped to a unit cube with the origin (0, 0, 0) in the
* center, x, y and z ranging from -1 to 1 with (-1, -1) being top
* left and (1, 1) bottom right.
*
* This sets up a Clutter like coordinate system for a Cogl
* framebuffer
*/
void
setup_viewport (unsigned int width,
unsigned int height,
float fovy,
float aspect,
float z_near,
float z_far)
{
float z_camera;
CoglMatrix projection_matrix;
CoglMatrix mv_matrix;
cogl_set_viewport (0, 0, width, height);
/* For Ortho projection.
* _cogl_matrix_stack_ortho (projection_stack, 0, width, 0, height, -1, 1);
*/
cogl_perspective (fovy, aspect, z_near, z_far);
/*
* In theory, we can compute the camera distance from screen as:
*
* 0.5 * tan (FOV)
*
* However, it's better to compute the z_camera from our projection
* matrix so that we get a 1:1 mapping at the screen distance. Consider
* the upper-left corner of the screen. It has object coordinates
* (0,0,0), so by the transform below, ends up with eye coordinate
*
* x_eye = x_object / width - 0.5 = - 0.5
* y_eye = (height - y_object) / width - 0.5 = 0.5
* z_eye = z_object / width - z_camera = - z_camera
*
* From cogl_perspective(), we know that the projection matrix has
* the form:
*
* (x, 0, 0, 0)
* (0, y, 0, 0)
* (0, 0, c, d)
* (0, 0, -1, 0)
*
* Applied to the above, we get clip coordinates of
*
* x_clip = x * (- 0.5)
* y_clip = y * 0.5
* w_clip = - 1 * (- z_camera) = z_camera
*
* Dividing through by w to get normalized device coordinates, we
* have, x_nd = x * 0.5 / z_camera, y_nd = - y * 0.5 / z_camera.
* The upper left corner of the screen has normalized device coordinates,
* (-1, 1), so to have the correct 1:1 mapping, we have to have:
*
* z_camera = 0.5 * x = 0.5 * y
*
* If x != y, then we have a non-uniform aspect ration, and a 1:1 mapping
* doesn't make sense.
*/
cogl_get_projection_matrix (&projection_matrix);
z_camera = 0.5 * projection_matrix.xx;
cogl_matrix_init_identity (&mv_matrix);
cogl_matrix_translate (&mv_matrix, -0.5f, -0.5f, -z_camera);
cogl_matrix_scale (&mv_matrix, 1.0f / width, -1.0f / height, 1.0f / width);
cogl_matrix_translate (&mv_matrix, 0.0f, -1.0 * height, 0.0f);
cogl_set_modelview_matrix (&mv_matrix);
}
static void
test_coglbox_map (ClutterActor *actor)
{
TestCoglboxPrivate *priv = TEST_COGLBOX_GET_PRIVATE (actor);
ClutterActor *stage;
ClutterPerspective perspective;
float stage_width;
float stage_height;
CLUTTER_ACTOR_CLASS (test_coglbox_parent_class)->map (actor);
printf ("Creating offscreen\n");
priv->offscreen_id = cogl_offscreen_new_to_texture (priv->texture_id);
stage = clutter_actor_get_stage (actor);
clutter_stage_get_perspective (CLUTTER_STAGE (stage), &perspective);
clutter_actor_get_size (stage, &stage_width, &stage_height);
cogl_push_framebuffer (priv->offscreen_id);
setup_viewport (stage_width, stage_height,
perspective.fovy,
perspective.aspect,
perspective.z_near,
perspective.z_far);
cogl_pop_framebuffer ();
if (priv->offscreen_id == COGL_INVALID_HANDLE)
printf ("Failed creating offscreen to texture!\n");
}
static void
test_coglbox_init (TestCoglbox *self)
{
TestCoglboxPrivate *priv;
gchar *file;
self->priv = priv = TEST_COGLBOX_GET_PRIVATE(self);
printf ("Loading redhand.png\n");
file = g_build_filename (TESTS_DATADIR, "redhand.png", NULL);
priv->texhand_id = cogl_texture_new_from_file (file,
COGL_TEXTURE_NONE,
COGL_PIXEL_FORMAT_ANY,
NULL);
g_free (file);
printf ("Creating texture with size\n");
priv->texture_id = cogl_texture_new_with_size (200, 200,
COGL_TEXTURE_NONE,
COGL_PIXEL_FORMAT_RGB_888);
if (priv->texture_id == COGL_INVALID_HANDLE)
printf ("Failed creating texture with size!\n");
}
static void
test_coglbox_class_init (TestCoglboxClass *klass)
{
GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
ClutterActorClass *actor_class = CLUTTER_ACTOR_CLASS (klass);
gobject_class->finalize = test_coglbox_finalize;
gobject_class->dispose = test_coglbox_dispose;
actor_class->map = test_coglbox_map;
actor_class->paint = test_coglbox_paint;
g_type_class_add_private (gobject_class, sizeof (TestCoglboxPrivate));
}
static ClutterActor*
test_coglbox_new (void)
{
return g_object_new (TEST_TYPE_COGLBOX, NULL);
}
G_MODULE_EXPORT int
test_cogl_offscreen_main (int argc, char *argv[])
{
ClutterActor *stage;
ClutterActor *coglbox;
if (clutter_init (&argc, &argv) != CLUTTER_INIT_SUCCESS)
return 1;
/* Stage */
stage = clutter_stage_new ();
clutter_actor_set_size (stage, 400, 400);
clutter_stage_set_title (CLUTTER_STAGE (stage), "Cogl Offscreen Buffers");
g_signal_connect (stage, "destroy", G_CALLBACK (clutter_main_quit), NULL);
/* Cogl Box */
coglbox = test_coglbox_new ();
clutter_container_add_actor (CLUTTER_CONTAINER (stage), coglbox);
clutter_actor_show_all (stage);
clutter_main ();
return 0;
}
G_MODULE_EXPORT const char *
test_cogl_offscreen_describe (void)
{
return "Offscreen buffer support in Cogl.";
}