#include <cogl/cogl.h>
#include <cogl-pango/cogl-pango.h>
/* The state for this example... */
typedef struct _Data
{
CoglFramebuffer *fb;
int framebuffer_width;
int framebuffer_height;
CoglMatrix view;
CoglIndices *indices;
CoglPrimitive *prim;
CoglTexture *texture;
CoglPipeline *crate_pipeline;
CoglPangoFontMap *pango_font_map;
PangoContext *pango_context;
PangoFontDescription *pango_font_desc;
PangoLayout *hello_label;
int hello_label_width;
int hello_label_height;
GTimer *timer;
gboolean swap_ready;
} Data;
/* A static identity matrix initialized for convenience. */
static CoglMatrix identity;
/* static colors initialized for convenience. */
static CoglColor white;
/* A cube modelled using 4 vertices for each face.
*
* We use an index buffer when drawing the cube later so the GPU will
* actually read each face as 2 separate triangles.
*/
static CoglVertexP3T2 vertices[] =
{
/* Front face */
{ /* pos = */ -1.0f, -1.0f, 1.0f, /* tex coords = */ 0.0f, 1.0f},
{ /* pos = */ 1.0f, -1.0f, 1.0f, /* tex coords = */ 1.0f, 1.0f},
{ /* pos = */ 1.0f, 1.0f, 1.0f, /* tex coords = */ 1.0f, 0.0f},
{ /* pos = */ -1.0f, 1.0f, 1.0f, /* tex coords = */ 0.0f, 0.0f},
/* Back face */
{ /* pos = */ -1.0f, -1.0f, -1.0f, /* tex coords = */ 1.0f, 0.0f},
{ /* pos = */ -1.0f, 1.0f, -1.0f, /* tex coords = */ 1.0f, 1.0f},
{ /* pos = */ 1.0f, 1.0f, -1.0f, /* tex coords = */ 0.0f, 1.0f},
{ /* pos = */ 1.0f, -1.0f, -1.0f, /* tex coords = */ 0.0f, 0.0f},
/* Top face */
{ /* pos = */ -1.0f, 1.0f, -1.0f, /* tex coords = */ 0.0f, 1.0f},
{ /* pos = */ -1.0f, 1.0f, 1.0f, /* tex coords = */ 0.0f, 0.0f},
{ /* pos = */ 1.0f, 1.0f, 1.0f, /* tex coords = */ 1.0f, 0.0f},
{ /* pos = */ 1.0f, 1.0f, -1.0f, /* tex coords = */ 1.0f, 1.0f},
/* Bottom face */
{ /* pos = */ -1.0f, -1.0f, -1.0f, /* tex coords = */ 1.0f, 1.0f},
{ /* pos = */ 1.0f, -1.0f, -1.0f, /* tex coords = */ 0.0f, 1.0f},
{ /* pos = */ 1.0f, -1.0f, 1.0f, /* tex coords = */ 0.0f, 0.0f},
{ /* pos = */ -1.0f, -1.0f, 1.0f, /* tex coords = */ 1.0f, 0.0f},
/* Right face */
{ /* pos = */ 1.0f, -1.0f, -1.0f, /* tex coords = */ 1.0f, 0.0f},
{ /* pos = */ 1.0f, 1.0f, -1.0f, /* tex coords = */ 1.0f, 1.0f},
{ /* pos = */ 1.0f, 1.0f, 1.0f, /* tex coords = */ 0.0f, 1.0f},
{ /* pos = */ 1.0f, -1.0f, 1.0f, /* tex coords = */ 0.0f, 0.0f},
/* Left face */
{ /* pos = */ -1.0f, -1.0f, -1.0f, /* tex coords = */ 0.0f, 0.0f},
{ /* pos = */ -1.0f, -1.0f, 1.0f, /* tex coords = */ 1.0f, 0.0f},
{ /* pos = */ -1.0f, 1.0f, 1.0f, /* tex coords = */ 1.0f, 1.0f},
{ /* pos = */ -1.0f, 1.0f, -1.0f, /* tex coords = */ 0.0f, 1.0f}
};
static void
paint (Data *data)
{
CoglFramebuffer *fb = data->fb;
float rotation;
cogl_framebuffer_clear4f (fb,
COGL_BUFFER_BIT_COLOR|COGL_BUFFER_BIT_DEPTH,
0, 0, 0, 1);
cogl_framebuffer_push_matrix (fb);
cogl_framebuffer_translate (fb,
data->framebuffer_width / 2,
data->framebuffer_height / 2,
0);
cogl_framebuffer_scale (fb, 75, 75, 75);
/* Update the rotation based on the time the application has been
running so that we get a linear animation regardless of the frame
rate */
rotation = g_timer_elapsed (data->timer, NULL) * 60.0f;
/* Rotate the cube separately around each axis.
*
* Note: Cogl matrix manipulation follows the same rules as for
* OpenGL. We use column-major matrices and - if you consider the
* transformations happening to the model - then they are combined
* in reverse order which is why the rotation is done last, since
* we want it to be a rotation around the origin, before it is
* scaled and translated.
*/
cogl_framebuffer_rotate (fb, rotation, 0, 0, 1);
cogl_framebuffer_rotate (fb, rotation, 0, 1, 0);
cogl_framebuffer_rotate (fb, rotation, 1, 0, 0);
cogl_framebuffer_draw_primitive (fb, data->crate_pipeline, data->prim);
cogl_framebuffer_pop_matrix (fb);
/* And finally render our Pango layouts... */
cogl_pango_render_layout (data->hello_label,
(data->framebuffer_width / 2) -
(data->hello_label_width / 2),
(data->framebuffer_height / 2) -
(data->hello_label_height / 2),
&white, 0);
}
static void
swap_notify_cb (CoglFramebuffer *framebuffer,
void *user_data)
{
Data *data = user_data;
data->swap_ready = TRUE;
}
int
main (int argc, char **argv)
{
CoglContext *ctx;
CoglOnscreen *onscreen;
CoglFramebuffer *fb;
GError *error = NULL;
Data data;
PangoRectangle hello_label_size;
float fovy, aspect, z_near, z_2d, z_far;
CoglDepthState depth_state;
gboolean has_swap_notify;
g_type_init ();
ctx = cogl_context_new (NULL, &error);
if (!ctx) {
fprintf (stderr, "Failed to create context: %s\n", error->message);
return 1;
}
onscreen = cogl_onscreen_new (ctx, 640, 480);
fb = COGL_FRAMEBUFFER (onscreen);
data.fb = fb;
data.framebuffer_width = cogl_framebuffer_get_width (fb);
data.framebuffer_height = cogl_framebuffer_get_height (fb);
data.timer = g_timer_new ();
cogl_onscreen_show (onscreen);
cogl_push_framebuffer (fb);
cogl_set_viewport (0, 0, data.framebuffer_width, data.framebuffer_height);
fovy = 60; /* y-axis field of view */
aspect = (float)data.framebuffer_width/(float)data.framebuffer_height;
z_near = 0.1; /* distance to near clipping plane */
z_2d = 1000; /* position to 2d plane */
z_far = 2000; /* distance to far clipping plane */
cogl_perspective (fovy, aspect, z_near, z_far);
/* Since the pango renderer emits geometry in pixel/device coordinates
* and the anti aliasing is implemented with the assumption that the
* geometry *really* does end up pixel aligned, we setup a modelview
* matrix so that for geometry in the plane z = 0 we exactly map x
* coordinates in the range [0,stage_width] and y coordinates in the
* range [0,stage_height] to the framebuffer extents with (0,0) being
* the top left.
*
* This is roughly what Clutter does for a ClutterStage, but this
* demonstrates how it is done manually using Cogl.
*/
cogl_matrix_init_identity (&data.view);
cogl_matrix_view_2d_in_perspective (&data.view, fovy, aspect, z_near, z_2d,
data.framebuffer_width,
data.framebuffer_height);
cogl_set_modelview_matrix (&data.view);
cogl_pop_framebuffer ();
/* Initialize some convenient constants */
cogl_matrix_init_identity (&identity);
cogl_color_set_from_4ub (&white, 0xff, 0xff, 0xff, 0xff);
/* rectangle indices allow the GPU to interpret a list of quads (the
* faces of our cube) as a list of triangles.
*
* Since this is a very common thing to do
* cogl_get_rectangle_indices() is a convenience function for
* accessing internal index buffers that can be shared.
*/
data.indices = cogl_get_rectangle_indices (ctx, 6 /* n_rectangles */);
data.prim = cogl_primitive_new_p3t2 (ctx, COGL_VERTICES_MODE_TRIANGLES,
G_N_ELEMENTS (vertices),
vertices);
/* Each face will have 6 indices so we have 6 * 6 indices in total... */
cogl_primitive_set_indices (data.prim,
data.indices,
6 * 6);
/* Load a jpeg crate texture from a file */
printf ("crate.jpg (CC by-nc-nd http://bit.ly/9kP45T) ShadowRunner27 http://bit.ly/m1YXLh\n");
data.texture = cogl_texture_new_from_file (COGL_EXAMPLES_DATA "crate.jpg",
COGL_TEXTURE_NO_SLICING,
COGL_PIXEL_FORMAT_ANY,
NULL);
if (!data.texture)
g_error ("Failed to load texture");
/* a CoglPipeline conceptually describes all the state for vertex
* processing, fragment processing and blending geometry. When
* drawing the geometry for the crate this pipeline says to sample a
* single texture during fragment processing... */
data.crate_pipeline = cogl_pipeline_new (ctx);
cogl_pipeline_set_layer_texture (data.crate_pipeline, 0, data.texture);
/* Since the box is made of multiple triangles that will overlap
* when drawn and we don't control the order they are drawn in, we
* enable depth testing to make sure that triangles that shouldn't
* be visible get culled by the GPU. */
cogl_depth_state_init (&depth_state);
cogl_depth_state_set_test_enabled (&depth_state, TRUE);
cogl_pipeline_set_depth_state (data.crate_pipeline, &depth_state, NULL);
/* Setup a Pango font map and context */
data.pango_font_map = COGL_PANGO_FONT_MAP (cogl_pango_font_map_new());
cogl_pango_font_map_set_use_mipmapping (data.pango_font_map, TRUE);
data.pango_context = cogl_pango_font_map_create_context (data.pango_font_map);
data.pango_font_desc = pango_font_description_new ();
pango_font_description_set_family (data.pango_font_desc, "Sans");
pango_font_description_set_size (data.pango_font_desc, 30 * PANGO_SCALE);
/* Setup the "Hello Cogl" text */
data.hello_label = pango_layout_new (data.pango_context);
pango_layout_set_font_description (data.hello_label, data.pango_font_desc);
pango_layout_set_text (data.hello_label, "Hello Cogl", -1);
pango_layout_get_extents (data.hello_label, NULL, &hello_label_size);
data.hello_label_width = PANGO_PIXELS (hello_label_size.width);
data.hello_label_height = PANGO_PIXELS (hello_label_size.height);
cogl_push_framebuffer (fb);
data.swap_ready = TRUE;
has_swap_notify =
cogl_has_feature (ctx, COGL_FEATURE_ID_SWAP_BUFFERS_EVENT);
if (has_swap_notify)
cogl_onscreen_add_swap_buffers_callback (COGL_ONSCREEN (fb),
swap_notify_cb,
&data);
while (1)
{
CoglPollFD *poll_fds;
int n_poll_fds;
gint64 timeout;
if (data.swap_ready)
{
paint (&data);
cogl_onscreen_swap_buffers (COGL_ONSCREEN (fb));
}
cogl_poll_get_info (ctx, &poll_fds, &n_poll_fds, &timeout);
if (!has_swap_notify)
{
/* If the winsys doesn't support swap event notification
then we'll just redraw constantly */
data.swap_ready = TRUE;
timeout = 0;
}
g_poll ((GPollFD *) poll_fds, n_poll_fds,
timeout == -1 ? -1 : timeout / 1000);
cogl_poll_dispatch (ctx, poll_fds, n_poll_fds);
}
return 0;
}