Utility API

Utility API

Synopsis

gboolean            cogl_create_context                 (void);
void                cogl_destroy_context                (void);
#define             COGL_INVALID_HANDLE
typedef             CoglHandle;
void                (*CoglFuncPtr)                      (void);

enum                CoglFeatureFlags;
ClutterFeatureFlags cogl_get_features                   (void);
gboolean            cogl_features_available             (CoglFeatureFlags features);

CoglFuncPtr         cogl_get_proc_address               (const gchar *name);
gboolean            cogl_check_extension                (const gchar *name,
                                                         const gchar *ext);
void                cogl_get_bitmasks                   (gint *red,
                                                         gint *green,
                                                         gint *blue,
                                                         gint *alpha);
void                cogl_paint_init                     (const ClutterColor *color);

int                 cogl_util_next_p2                   (int a);

Description

Details

cogl_create_context ()

gboolean            cogl_create_context                 (void);

FIXME

Returns :


cogl_destroy_context ()

void                cogl_destroy_context                (void);

FIXME


COGL_INVALID_HANDLE

#define COGL_INVALID_HANDLE NULL

A COGL handle that is not valid, used for unitialized handles as well as error conditions.


CoglHandle

typedef gpointer CoglHandle;

Type used for storing references to cogl objects, the CoglHandle is a fully opaque type without any public data members.


CoglFuncPtr ()

void                (*CoglFuncPtr)                      (void);

The type used by cogl for function pointers, note that this type is used as a generic catch-all cast for function pointers and the actual arguments and return type may be different.


enum CoglFeatureFlags

typedef enum
{
  COGL_FEATURE_TEXTURE_RECTANGLE      = (1 << 1),
  COGL_FEATURE_TEXTURE_NPOT           = (1 << 2),
  COGL_FEATURE_TEXTURE_YUV            = (1 << 3),
  COGL_FEATURE_TEXTURE_READ_PIXELS    = (1 << 4),
  COGL_FEATURE_SHADERS_GLSL           = (1 << 5),
  COGL_FEATURE_OFFSCREEN              = (1 << 6),
  COGL_FEATURE_OFFSCREEN_MULTISAMPLE  = (1 << 7),
  COGL_FEATURE_OFFSCREEN_BLIT         = (1 << 8),
  COGL_FEATURE_FOUR_CLIP_PLANES       = (1 << 9),
  COGL_FEATURE_STENCIL_BUFFER         = (1 << 10)

} CoglFeatureFlags;

Flags for the supported features.


cogl_get_features ()

ClutterFeatureFlags cogl_get_features                   (void);

Returns all of the features supported by COGL.

Returns :

A logical OR of all the supported COGL features.

Since 0.8


cogl_features_available ()

gboolean            cogl_features_available             (CoglFeatureFlags features);

Checks whether the given COGL features are available. Multiple features can be checked for by or-ing them together with the '|' operator. TRUE is only returned if all of the requested features are available.

features :

A bitmask of features to check for

Returns :

TRUE if the features are available, FALSE otherwise.

cogl_get_proc_address ()

CoglFuncPtr         cogl_get_proc_address               (const gchar *name);

Gets a pointer to a given GL or GL ES extension function. This acts as a wrapper around glXGetProcAddress() or whatever is the appropriate function for the current backend.

name :

the name of the function.

Returns :

a pointer to the requested function or NULL if the function is not available.

cogl_check_extension ()

gboolean            cogl_check_extension                (const gchar *name,
                                                         const gchar *ext);

Check whether name occurs in list of extensions in ext.

name :

extension to check for

ext :

list of extensions

Returns :

TRUE if the extension occurs in the list, FALSE otherwize.

cogl_get_bitmasks ()

void                cogl_get_bitmasks                   (gint *red,
                                                         gint *green,
                                                         gint *blue,
                                                         gint *alpha);

Gets the number of bitplanes used for each of the color components in the color buffer. Pass NULL for any of the arguments if the value is not required.

red :

Return location for the number of red bits or NULL

green :

Return location for the number of green bits or NULL

blue :

Return location for the number of blue bits or NULL

alpha :

Return location for the number of alpha bits or NULL

cogl_paint_init ()

void                cogl_paint_init                     (const ClutterColor *color);

Clears the color buffer to color. The depth buffer and stencil buffers are also cleared and fogging and lighting are disabled.

color :

Background color to clear to

cogl_util_next_p2 ()

int                 cogl_util_next_p2                   (int a);

Calculates the next power greater than a.

a :

Value to get the next power

Returns :

The next power after a.