/* * Cogl * * An object oriented GL/GLES Abstraction/Utility Layer * * Copyright (C) 2008,2009 Intel Corporation. * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser 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 * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the * Free Software Foundation, Inc., 59 Temple Place - Suite 330, * Boston, MA 02111-1307, USA. */ #ifndef __COGL_H__ #define __COGL_H__ #include #define __COGL_H_INSIDE__ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include G_BEGIN_DECLS /** * SECTION:cogl * @short_description: General purpose API * * General utility functions for COGL. */ /** * cogl_get_option_group: * * Retrieves the #GOptionGroup used by COGL to parse the command * line options. Clutter uses this to handle the COGL command line * options during its initialization process. * * Return value: a #GOptionGroup * * Since: 1.0 */ GOptionGroup * cogl_get_option_group (void); /* Misc */ /** * cogl_get_features: * * Returns all of the features supported by COGL. * * Return value: A logical OR of all the supported COGL features. * * Since: 0.8 */ CoglFeatureFlags cogl_get_features (void); /** * cogl_features_available: * @features: A bitmask of features to check for * * 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. * * Return value: %TRUE if the features are available, %FALSE otherwise. */ gboolean cogl_features_available (CoglFeatureFlags features); /** * cogl_get_proc_address: * @name: the name of the function. * * 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. * * Return value: a pointer to the requested function or %NULL if the * function is not available. */ CoglFuncPtr cogl_get_proc_address (const gchar *name); /** * cogl_check_extension: * @name: extension to check for * @ext: list of extensions * * Check whether @name occurs in list of extensions in @ext. * * Returns: %TRUE if the extension occurs in the list, %FALSE otherwize. */ gboolean cogl_check_extension (const gchar *name, const gchar *ext); /** * cogl_get_bitmasks: * @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 * * 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. */ void cogl_get_bitmasks (gint *red, gint *green, gint *blue, gint *alpha); /** * cogl_perspective: * @fovy: Vertical of view angle in degrees. * @aspect: Aspect ratio of diesplay * @z_near: Nearest visible point * @z_far: Furthest visible point along the z-axis * * Replaces the current projection matrix with a perspective matrix * based on the provided values. */ void cogl_perspective (float fovy, float aspect, float z_near, float z_far); /** * cogl_frustum: * @left: Left clipping plane * @right: Right clipping plane * @bottom: Bottom clipping plane * @top: Top clipping plane * @z_near: Nearest visible point * @z_far: Furthest visible point along the z-axis * * Replaces the current projection matrix with a perspective matrix * for the given viewing frustum. * * Since: 0.8.2 */ void cogl_frustum (float left, float right, float bottom, float top, float z_near, float z_far); /** * cogl_ortho: * @left: The coordinate for the left clipping plane * @right: The coordinate for the right clipping plane * @bottom: The coordinate for the bottom clipping plane * @top: The coordinate for the top clipping plane * @near: The coordinate for the near clipping plane (may be negative if * the plane is behind the viewer) * @far: The coordinate for the far clipping plane (may be negative if * the plane is behind the viewer) * * Replaces the current projection matrix with a parallel projection * matrix. * * Since: 1.0 */ void cogl_ortho (float left, float right, float bottom, float top, float near, float far); /* * _cogl_setup_viewport: * @width: Width of the viewport * @height: Height of the viewport * @fovy: Field of view angle in degrees * @aspect: Aspect ratio to determine the field of view along the x-axis * @z_near: Nearest visible point along the z-axis * @z_far: Furthest visible point along the z-axis * * Replaces the current viewport and projection matrix with the given * values. The viewport is placed at the top left corner of the window * with the given width and height. The projection matrix is replaced * with one that has a viewing angle of @fovy along the y-axis and a * view scaled according to @aspect along the x-axis. The view is * clipped according to @z_near and @z_far on the z-axis. * * This function is used only by Clutter. */ void _cogl_setup_viewport (guint width, guint height, float fovy, float aspect, float z_near, float z_far); /** * cogl_viewport: * @width: Width of the viewport * @height: Height of the viewport * * Replace the current viewport with the given values. * * Since: 0.8.2 */ void cogl_viewport (guint width, guint height); /** * cogl_push_matrix: * * Store the current model-view matrix on the matrix stack. The matrix * can later be restored with cogl_pop_matrix(). */ void cogl_push_matrix (void); /** * cogl_pop_matrix: * * Restore the current model-view matrix from the matrix stack. */ void cogl_pop_matrix (void); /** * cogl_scale: * @x: Amount to scale along the x-axis * @y: Amount to scale along the y-axis * @z: Amount to scale along the z-axis * * Multiplies the current model-view matrix by one that scales the x, * y and z axes by the given values. */ void cogl_scale (float x, float y, float z); /** * cogl_translate: * @x: Distance to translate along the x-axis * @y: Distance to translate along the y-axis * @z: Distance to translate along the z-axis * * Multiplies the current model-view matrix by one that translates the * model along all three axes according to the given values. */ void cogl_translate (float x, float y, float z); /** * cogl_rotate: * @angle: Angle in degrees to rotate. * @x: X-component of vertex to rotate around. * @y: Y-component of vertex to rotate around. * @z: Z-component of vertex to rotate around. * * Multiplies the current model-view matrix by one that rotates the * model around the vertex specified by @x, @y and @z. The rotation * follows the right-hand thumb rule so for example rotating by 10 * degrees about the vertex (0, 0, 1) causes a small counter-clockwise * rotation. */ void cogl_rotate (float angle, float x, float y, float z); /** * cogl_get_modelview_matrix: * @matrix: pointer to a CoglMatrix to recieve the matrix * * Stores the current model-view matrix in @matrix. */ void cogl_get_modelview_matrix (CoglMatrix *matrix); /** * cogl_set_modelview_matrix: * @matrix: pointer to a CoglMatrix to set as the new model-view matrix * * Loads matrix as the new model-view matrix. */ void cogl_set_modelview_matrix (CoglMatrix *matrix); /** * cogl_get_projection_matrix: * @matrix: pointer to a CoglMatrix to recieve the matrix * * Stores the current projection matrix in @matrix. */ void cogl_get_projection_matrix (CoglMatrix *matrix); /** * cogl_set_projection_matrix: * @matrix: pointer to a CoglMatrix to set as the new projection matrix * * Loads matrix as the new projection matrix. */ void cogl_set_projection_matrix (CoglMatrix *matrix); /** * cogl_get_viewport: * @v: pointer to a 4 element array of #floats to * receive the viewport dimensions. * * Stores the current viewport in @v. @v[0] and @v[1] get the x and y * position of the viewport and @v[2] and @v[3] get the width and * height. */ void cogl_get_viewport (float v[4]); /** * cogl_set_depth_test_enabled: * @setting: %TRUE to enable depth testing or %FALSE to disable. * * Sets whether depth testing is enabled. If it is disabled then the * order that actors are layered on the screen depends solely on the * order specified using clutter_actor_raise() and * clutter_actor_lower(), otherwise it will also take into account the * actor's depth. Depth testing is disabled by default. */ void cogl_set_depth_test_enabled (gboolean setting); /** * cogl_get_depth_test_enabled: * * Queries if depth testing has been enabled via cogl_set_depth_test_enable() * * Returns: %TRUE if depth testing is enabled, and %FALSE otherwise */ gboolean cogl_get_depth_test_enabled (void); /** * cogl_set_backface_culling_enabled: * @setting: %TRUE to enable backface culling or %FALSE to disable. * * Sets whether textures positioned so that their backface is showing * should be hidden. This can be used to efficiently draw two-sided * textures or fully closed cubes without enabling depth testing. This * only affects calls to the cogl_rectangle* family of functions and * cogl_vertex_buffer_draw*. Backface culling is disabled by default. */ void cogl_set_backface_culling_enabled (gboolean setting); /** * cogl_get_backface_culling_enabled: * * Queries if backface culling has been enabled via * cogl_set_backface_culling_enabled() * * Returns: %TRUE if backface culling is enabled, and %FALSE otherwise */ gboolean cogl_get_backface_culling_enabled (void); /** * cogl_set_fog: * @fog_color: The color of the fog * @mode: A CoglFogMode that determines the equation used to calculate the * fogging blend factor. * @density: Used by the EXPONENTIAL and EXPONENTIAL_SQUARED CoglFogMode * equations. * @z_near: Position along z-axis where no fogging should be applied * @z_far: Position along z-axes where full fogging should be applied * * Enables fogging. Fogging causes vertices that are further away from the eye * to be rendered with a different color. The color is determined according to * the chosen fog mode; at it's simplest the color is linearly interpolated so * that vertices at @z_near are drawn fully with their original color and * vertices at @z_far are drawn fully with @fog_color. Fogging will remain * enabled until you call cogl_disable_fog(). * * The fogging functions only work correctly when primitives use * unmultiplied alpha colors. By default Cogl will premultiply textures * and cogl_set_source_color() will premultiply colors, so unless you * explicitly load your textures requesting an unmultiplied internal format * and use cogl_material_set_color() you can only use fogging with fully * opaque primitives. This might improve in the future when we can depend * on fragment shaders. */ void cogl_set_fog (const CoglColor *fog_color, CoglFogMode mode, float density, float z_near, float z_far); /** * cogl_disable_fog: * * This function disables fogging, so primitives drawn afterwards will not be * blended with any previously set fog color. */ void cogl_disable_fog (void); /** * CoglBufferBit: * @COGL_BUFFER_BIT_COLOR: Selects the primary color buffer * @COGL_BUFFER_BIT_DEPTH: Selects the depth buffer * @COGL_BUFFER_BIT_STENCIL: Selects the stencil buffer * * Types of auxiliary buffers * * Since: 1.0 */ typedef enum { COGL_BUFFER_BIT_COLOR = 1L<<0, COGL_BUFFER_BIT_DEPTH = 1L<<1, COGL_BUFFER_BIT_STENCIL = 1L<<2 } CoglBufferBit; /** * cogl_clear: * @color: Background color to clear to * @buffers: A mask of #CoglBufferBit's identifying which auxiliary * buffers to clear * * Clears all the auxiliary buffers identified in the @buffers mask, and if * that includes the color buffer then the specified @color is used. */ void cogl_clear (const CoglColor *color, gulong buffers); /** * cogl_set_source: * @material: A CoglMaterial object * * This function sets the source material that will be used to fill subsequent * geometry emitted via the cogl API. * * Note: in the future we may add the ability to set a front facing material, * and a back facing material, in which case this function will set both to the * same. * * Since 1.0 */ void cogl_set_source (CoglHandle material); /** * cogl_set_source_color: * @color: a #CoglColor * * This is a convenience function for creating a solid fill source material * from the given color. This color will be used for any subsequent drawing * operation. * * The color will be premultiplied by Cogl, so the color should be * non-premultiplied. For example: use (1.0, 0.0, 0.0, 0.5) for * semi-transparent red. * * See also cogl_set_source_color4ub() and cogl_set_source_color4f() * if you already have the color components. * * Since: 1.0 */ void cogl_set_source_color (const CoglColor *color); /** * cogl_set_source_color4ub: * @red: value of the red channel, between 0 and 255 * @green: value of the green channel, between 0 and 255 * @blue: value of the blue channel, between 0 and 255 * @alpha: value of the alpha channel, between 0 and 255 * * This is a convenience function for creating a solid fill source material * from the given color using unsigned bytes for each component. This * color will be used for any subsequent drawing operation. * * The value for each component is an unsigned byte in the range * between 0 and 255. * * Since: 1.0 */ void cogl_set_source_color4ub (guint8 red, guint8 green, guint8 blue, guint8 alpha); /** * cogl_set_source_color4f: * @red: value of the red channel, between 0 and %1.0 * @green: value of the green channel, between 0 and %1.0 * @blue: value of the blue channel, between 0 and %1.0 * @alpha: value of the alpha channel, between 0 and %1.0 * * This is a convenience function for creating a solid fill source material * from the given color using normalized values for each component. This color * will be used for any subsequent drawing operation. * * The value for each component is a fixed point number in the range * between 0 and %1.0. If the values passed in are outside that * range, they will be clamped. * * Since: 1.0 */ void cogl_set_source_color4f (float red, float green, float blue, float alpha); /** * cogl_set_source_texture: * @texture_handle: The Cogl texture you want as your source * * This is a convenience function for creating a material with the first * layer set to #texture_handle and setting that material as the source with * cogl_set_source. * * Note: There is no interaction between calls to cogl_set_source_color * and cogl_set_source_texture. If you need to blend a texture with a color then * you can create a simple material like this: * * material = cogl_material_new (); * cogl_material_set_color4ub (material, 0xff, 0x00, 0x00, 0x80); * cogl_material_set_layer (material, 0, tex_handle); * cogl_set_source (material); * * * Since 1.0 */ void cogl_set_source_texture (CoglHandle texture_handle); /** * SECTION:cogl-clipping * @short_description: Fuctions for manipulating a stack of clipping regions * * To support clipping your geometry to rectangles or paths Cogl exposes a * stack based API whereby each clip region you push onto the stack is * intersected with the previous region. */ /** * cogl_clip_push_window_rect: * @x_offset: left edge of the clip rectangle in window coordinates * @y_offset: top edge of the clip rectangle in window coordinates * @width: width of the clip rectangle * @height: height of the clip rectangle * * Specifies a rectangular clipping area for all subsequent drawing * operations. Any drawing commands that extend outside the rectangle * will be clipped so that only the portion inside the rectangle will * be displayed. The rectangle dimensions are not transformed by the * current model-view matrix. * * The rectangle is intersected with the current clip region. To undo * the effect of this function, call cogl_clip_pop(). */ void cogl_clip_push_window_rect (float x_offset, float y_offset, float width, float height); /** * cogl_clip_push: * @x_offset: left edge of the clip rectangle * @y_offset: top edge of the clip rectangle * @width: width of the clip rectangle * @height: height of the clip rectangle * * Specifies a rectangular clipping area for all subsequent drawing * operations. Any drawing commands that extend outside the rectangle * will be clipped so that only the portion inside the rectangle will * be displayed. The rectangle dimensions are transformed by the * current model-view matrix. * * The rectangle is intersected with the current clip region. To undo * the effect of this function, call cogl_clip_pop(). */ void cogl_clip_push (float x_offset, float y_offset, float width, float height); /** * cogl_clip_push_from_path: * * Sets a new clipping area using the current path. The current path * is then cleared. The clipping area is intersected with the previous * clipping area. To restore the previous clipping area, call * cogl_clip_pop(). * * Since: 1.0 */ void cogl_clip_push_from_path (void); /** * cogl_clip_push_from_path_preserve: * * Sets a new clipping area using the current path. The current path * is then cleared. The clipping area is intersected with the previous * clipping area. To restore the previous clipping area, call * cogl_clip_pop(). * * Since: 1.0 */ void cogl_clip_push_from_path_preserve (void); /** * cogl_clip_pop: * * Reverts the clipping region to the state before the last call to * cogl_clip_push(). */ void cogl_clip_pop (void); /** * cogl_clip_ensure: * * Ensures that the current clipping region has been set in GL. This * will automatically be called before any Cogl primitives but it * maybe be neccessary to call if you are using raw GL calls with * clipping. * * Since: 1.0 */ void cogl_clip_ensure (void); /** * cogl_clip_stack_save: * * Save the entire state of the clipping stack and then clear all * clipping. The previous state can be returned to with * cogl_clip_stack_restore(). Each call to cogl_clip_push() after this * must be matched by a call to cogl_clip_pop() before calling * cogl_clip_stack_restore(). * * Since: 0.8.2 */ void cogl_clip_stack_save (void); /** * cogl_clip_stack_restore: * * Restore the state of the clipping stack that was previously saved * by cogl_clip_stack_save(). * * Since: 0.8.2 */ void cogl_clip_stack_restore (void); /** * cogl_set_draw_buffer: * @target: A #CoglBufferTarget that specifies what kind of draw buffer you * are setting as the render target. * @offscreen: If you are setting a draw buffer of type COGL_OFFSCREEN_BUFFER * then this is a CoglHandle for the offscreen buffer. * * This redirects all subsequent drawing to the specified draw buffer. This * can either be an offscreen buffer created with * cogl_offscreen_new_to_texture () or you can revert to your original * on screen window buffer. */ void cogl_set_draw_buffer (CoglBufferTarget target, CoglHandle offscreen); /** * cogl_push_draw_buffer: * * Save cogl_set_draw_buffer() state. */ void cogl_push_draw_buffer (void); /** * cogl_pop_draw_buffer: * * Restore cogl_set_draw_buffer() state. */ void cogl_pop_draw_buffer (void); /** * CoglReadPixelsFlags: * @COGL_READ_PIXELS_COLOR_BUFFER: Read from the color buffer * * Flags for cogl_read_pixels() * * Since: 1.0 */ typedef enum { /*< prefix=COGL_READ_PIXELS >*/ COGL_READ_PIXELS_COLOR_BUFFER = 1L << 0 } CoglReadPixelsFlags; /** * cogl_read_pixels: * @x: The window x position to start reading from * @y: The window y position to start reading from * @width: The width of the rectangle you want to read * @height: The height of the rectangle you want to read * @source: Identifies which auxillary buffer you want to read * (only COGL_READ_PIXELS_COLOR_BUFFER supported currently) * @format: The pixel format you want the result in * (only COGL_PIXEL_FORMAT_RGBA_8888 supported currently) * @pixels: The location to write the pixel data. * * This reads a rectangle of pixels from the current draw buffer where * position (0, 0) is the top left. The pixel at (x, y) is the first * read, and the data is returned with a rowstride of (width * 4) */ void cogl_read_pixels (int x, int y, int width, int height, CoglReadPixelsFlags source, CoglPixelFormat format, guint8 *pixels); /** * cogl_flush: * * This function should only need to be called in exceptional circumstances. * * As an optimization Cogl drawing functions may batch up primitives * internally, so if you are trying to use raw GL outside of Cogl you stand a * better chance of being successful if you ask Cogl to flush any batched * geometry before making your state changes. * * It only ensure that the underlying driver is issued all the commands * necessary to draw the batched primitives. It provides no guarantees about * when the driver will complete the rendering. * * This provides no guarantees about the GL state upon returning and to avoid * confusing Cogl you should aim to restore any changes you make before * resuming use of Cogl. * * If you are making state changes with the intention of affecting Cogl drawing * primitives you are 100% on your own since you stand a good chance of * conflicting with Cogl internals. For example clutter-gst which currently * uses direct GL calls to bind ARBfp programs will very likely break when Cogl * starts to use ARBfb programs itself for the material API. * * Since: 1.0 */ void cogl_flush (void); /** * cogl_begin_gl: * * We do not advise nor reliably support the interleaving of raw GL drawing and * Cogl drawing functions, but if you insist, cogl_begin_gl() and cogl_end_gl() * provide a simple mechanism that may at least give you a fighting chance of * succeeding. * * Note: this doesn't help you modify the behaviour of Cogl drawing functions * through the modification of GL state; that will never be reliably supported, * but if you are trying to do something like: * * { * - setup some OpenGL state. * - draw using OpenGL (e.g. glDrawArrays() ) * - reset modified OpenGL state. * - continue using Cogl to draw * } * * You should surround blocks of drawing using raw GL with cogl_begin_gl() * and cogl_end_gl(): * * { * cogl_begin_gl (); * - setup some OpenGL state. * - draw using OpenGL (e.g. glDrawArrays() ) * - reset modified OpenGL state. * cogl_end_gl (); * - continue using Cogl to draw * } * * * Don't ever try and do: * * { * - setup some OpenGL state. * - use Cogl to draw * - reset modified OpenGL state. * } * * When the internals of Cogl evolves, this is very liable to break. * * This function will flush all batched primitives, and subsequently flush * all internal Cogl state to OpenGL as if it were going to draw something * itself. * * The result is that the OpenGL modelview matrix will be setup; the state * corresponding to the current source material will be set up and other world * state such as backface culling, depth and fogging enabledness will be sent * to OpenGL. * * Note: no special material state is flushed, so if you want Cogl to setup a * simplified material state it is your responsibility to set a simple source * material before calling cogl_begin_gl. E.g. by calling * cogl_set_source_color4ub(). * * Note: It is your responsibility to restore any OpenGL state that you modify * to how it was after calling cogl_begin_gl() if you don't do this then the * result of further Cogl calls is undefined. * * Note: You can not nest begin/end blocks. * * Again we would like to stress, we do not advise the use of this API and if * possible we would prefer to improve Cogl than have developers require raw * OpenGL. * * Since: 1.0 */ void cogl_begin_gl (void); /** * cogl_end_gl: * * This is the counterpart to cogl_begin_gl() used to delimit blocks of drawing * code using raw OpenGL. Please refer to cogl_begin_gl() for full details. * * Since: 1.0 */ void cogl_end_gl (void); /* * Internal API available only to Clutter. * * These are typically only to deal with the poor seperation of * responsabilities that currently exists between Clutter and Cogl. * Eventually a lot of the backend code currently in Clutter will * move down into Cogl and these functions will be removed. */ void _cogl_destroy_context (void); /* XXX: Removed before we release Clutter 1.0 since the implementation * wasn't complete, and so we assume no one is using this yet. Util we * have some one with a good usecase, we can't pretend to support breaking * out into raw OpenGL. */ #if 0 /* * cogl_flush_gl_state: * @flags: flags controlling what is flushed; currently unused, pass in 0 * * As an optimization, COGL functions may not immediately modify GL's * state, instead batching up changes and applying them "just in * time." Unapplied state could include glEnable() flags and the * current transformation matrix among other examples. If you want to * use GL directly, you need to flush any state COGL may have kept * around. cogl_flush_gl_state() syncs all of COGL's state to GL. * * Since: 1.0 */ void cogl_flush_gl_state (int flags); #endif /* private */ void _cogl_set_indirect_context (gboolean indirect); void _cogl_set_viewport (int x, int y, int width, int height); void _cogl_onscreen_clutter_backend_set_size (int width, int height); G_END_DECLS #undef __COGL_H_INSIDE__ #endif /* __COGL_H__ */