bbutil.h

/*
 * Copyright (c) 2011-2012 Research In Motion Limited.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#ifndef _UTILITY_H_INCLUDED
#define _UTILITY_H_INCLUDED

#include <EGL/egl.h>
#include <screen/screen.h>
#include <sys/platform.h>

extern EGLDisplay egl_disp;
extern EGLSurface egl_surf;

typedef struct font_t font_t;

#define BBUTIL_DEFAULT_FONT "/usr/fonts/font_repository/monotype/arial.ttf"

#ifdef __cplusplus
extern "C" {
#endif

/**
 * Initializes EGL
 *
 * @param libscreen context that will be used for EGL setup
 * @return EXIT_SUCCESS if initialization succeeded otherwise EXIT_FAILURE
 */
int bbutil_init_egl(screen_context_t ctx);

/**
 * Terminates EGL
 */
void bbutil_terminate();

/**
 * Swaps default bbutil window surface to the screen
 */
void bbutil_swap();

/**
 * Loads the font from the specified font file.
 * NOTE: should be called after a successful return from bbutil_init() or bbutil_init_egl() call
 * @param font_file string indicating the absolute path of the font file
 * @param point_size used for glyph generation
 * @param dpi used for glyph generation
 * @return pointer to font_t structure on success or NULL on failure
 */
font_t* bbutil_load_font(const char* font_file, int point_size, int dpi);

/**
 * Destroys the passed font
 * @param font to be destroyed
 */
void bbutil_destroy_font(font_t* font);

/**
 * Renders the specified message using current font starting from the specified
 * bottom left coordinates.
 * NOTE: must be called after a successful return from bbutil_init() or bbutil_init_egl() call

 *
 * @param font to use for rendering
 * @param msg the message to display
 * @param x, y position of the bottom-left corner of text string in world coordinate space
 * @param rgba color for the text to render with
 */
void bbutil_render_text(font_t* font, const char* msg, float x, float y, float r, float g, float b, float a);

/**
 * Returns the non-scaled width and height of a string
 * NOTE: must be called after a successful return from bbutil_init() or bbutil_init_egl() call

 *
 * @param font to use for measurement of a string size
 * @param msg the message to get the size of
 * @param return pointer for width of a string
 * @param return pointer for height of a string
 */
void bbutil_measure_text(font_t* font, const  char* msg, float* width, float* height);

/**
 * Creates and loads a texture from a png file
 * NOTE: must be called after a successful return from bbutil_init() or bbutil_init_egl() call

 *
 * @param filename path to texture png
 * @param return width of texture
 * @param return height of texture
 * @param return gl texture handle
 * @return EXIT_SUCCESS if texture loading succeeded otherwise EXIT_FAILURE
 */

int bbutil_load_texture(const char* filename, int* width, int* height, float* tex_x, float* tex_y, unsigned int* tex);

/**
 * Returns dpi for a given screen

 *
 * @param ctx path libscreen context that corresponds to display of interest
 * @return dpi for a given screen
 */

int bbutil_calculate_dpi(screen_context_t ctx);

/**
 * Rotates the screen to a given angle

 *
 * @param angle to rotate screen surface to, must by 0, 90, 180, or 270
 * @return EXIT_SUCCESS if texture loading succeeded otherwise EXIT_FAILURE
 */

int bbutil_rotate_screen_surface(int angle);

#ifdef __cplusplus
}
#endif

#endif