/** \mainpage gLib2D Documentation
 *
 * \section intro Introduction
 *
 * gLib2D by Geecko - A simple, fast, light-weight 2D graphics library. \n\n
 * This library has been designed to replace the old graphics.c library
 * and to simplify the use of pspgu.\n
 * The goals : keep it simple, keep it small, keep it fast.
 *
 * \section limits Known limitations
 *
 * - Draw & display buffers can't actually be used as real textures. Just a way
 *     to get the vram pointer.
 * - No support for multiples contexts (e.g. sharing coordinates beetween
 *     textures using some gBegin calls at a time).
 * - Manipulating textures (clear, get pixel info...) is not possible.
 * - When some 512*512 rotated, colorized and scaled textures are rendered
 *     at a time, the framerate *could* go under 60 fps.
 *
 * \section install Installation
 *
 * - Simply put glib2d.c and glib2d.h in your source directory. \n
 * - Then add glib2d.o and link "-lpng -ljpeg -lz -lpspgu -lm -lpspvram"
 *     in your Makefile.
 * - You're done !
 *
 * \section copyright License
 *
 * This work is licensed under the LGPLv3 License. \n
 * See the LICENSE file for more details. \n
 * You can support the library by marking your homebrew with
 * "Using gLib2D by Geecko".
 *
 * \section contact Contact
 *
 * Please report bugs or submit ideas at : \n geecko.dev@free.fr \n\n
 * Get the full documentation on : \n http://geecko.dev.free.fr \n\n
 * Also stay tuned on... \n
 * https://github.com/GeeckoDev (contributors would be a plus!) \n
 * http://twitter.com/GeeckoDev
 */

/**
 * \file glib2d.h
 * \brief gLib2D Header
 * \version Beta 5
 */

#ifndef GLIB2D_H
#define GLIB2D_H

#ifdef __cplusplus
extern "C" {
#endif

#include <stdbool.h>

/**
 * \def G2D_SCR_W
 * \brief Screen width constant, in pixels.
 */
/**
 * \def G2D_SCR_H
 * \brief Screen height constant, in pixels.
 */
#define G2D_SCR_W (480)
#define G2D_SCR_H (272)

/**
 * \def G2D_RGBA(r,g,b,a)
 * \brief Create a g2dColor.
 *
 * This macro creates a g2dColor from 4 values, red, green, blue and alpha.
 * Input range is from 0 to 255.
 */
#define G2D_RGBA(r, g, b, a) ((r)|((g)<<8)|((b)<<16)|((a)<<24))

/**
 * \def G2D_GET_R(color)
 * \brief Get red channel value from a g2dColor.
 */
/**
 * \def G2D_GET_G(color)
 * \brief Get green channel value from a g2dColor.
 */
/**
 * \def G2D_GET_B(color)
 * \brief Get blue channel value from a g2dColor.
 */
/**
 * \def G2D_GET_A(color)
 * \brief Get alpha channel value from a g2dColor.
 */
#define G2D_GET_R(color) (((color)      ) & 0xFF)
#define G2D_GET_G(color) (((color) >>  8) & 0xFF)
#define G2D_GET_B(color) (((color) >> 16) & 0xFF)
#define G2D_GET_A(color) (((color) >> 24) & 0xFF)

/**
 * \def G2D_MODULATE(color,luminance,alpha)
 * \brief g2dColor modulation.
 *
 * This macro modulates the luminance & alpha of a g2dColor.
 * Input range is from 0 to 255.
 */
#define G2D_MODULATE(color,luminance,alpha) \
    G2D_RGBA((int)(luminance) * G2D_GET_R(color) / 255, \
             (int)(luminance) * G2D_GET_G(color) / 255, \
             (int)(luminance) * G2D_GET_B(color) / 255, \
             (int)(alpha    ) * G2D_GET_A(color) / 255)

/**
 * \enum g2dColors
 * \brief Colors enumeration.
 *
 * Primary, secondary, tertiary and grayscale colors are defined.
 */
enum g2dColors {
    // Primary colors
    RED             = 0xFF0000FF,
    GREEN           = 0xFF00FF00,
    BLUE            = 0xFFFF0000,
    // Secondary colors
    CYAN            = 0xFFFFFF00,
    MAGENTA         = 0xFFFF00FF,
    YELLOW          = 0xFF00FFFF,
    // Tertiary colors
    AZURE           = 0xFFFF7F00,
    VIOLET          = 0xFFFF007F,
    ROSE            = 0xFF7F00FF,
    ORANGE          = 0xFF007FFF,
    CHARTREUSE      = 0xFF00FF7F,
    SPRING_GREEN    = 0xFF7FFF00,
    // Grayscale
    WHITE           = 0xFFFFFFFF,
    LITEGRAY        = 0xFFBFBFBF,
    GRAY            = 0xFF7F7F7F,
    DARKGRAY        = 0xFF3F3F3F,
    BLACK           = 0xFF000000
};

/**
 * \enum g2dCoord_Mode
 * \brief Coordinates modes enumeration.
 *
 * Choose where the coordinates correspond in the object.
 * Can only be used with g2dSetCoordMode.
 */
/**
 * \enum g2dLine_Mode
 * \brief Line modes enumeration.
 *
 * Change line draw properties.
 * Can only be used with g2dBeginLines.
 */
/**
 * \enum g2dFlip_Mode
 * \brief Flip modes enumeration.
 *
 * Change flip properties.
 * Can only be used with g2dFlip.
 */
/**
 * \enum g2dTex_Mode
 * \brief Texture modes enumeration.
 *
 * Change texture properties.
 * Can only be used with g2dTexLoad.
 */
typedef enum {
    G2D_UP_LEFT,
    G2D_UP_RIGHT,
    G2D_DOWN_RIGHT,
    G2D_DOWN_LEFT,
    G2D_CENTER
} g2dCoord_Mode;
typedef enum {
    G2D_STRIP = 1 /**< Make a line strip. */
} g2dLine_Mode;
typedef enum {
    G2D_VSYNC = 1 /**< Limit the FPS to 60 (synchronized with the screen).
                       Better quality and less power consumption. */
} g2dFlip_Mode;
typedef enum {
    G2D_SWIZZLE = 1 /**< Recommended. Use it to speedup rendering. */
} g2dTex_Mode;

/**
 * \var g2dAlpha
 * \brief Alpha type.
 */
/**
 * \var g2dColor
 * \brief Color type.
 */
typedef int g2dAlpha;
typedef unsigned int g2dColor;

/**
 * \struct g2dTexture
 * \brief Texture structure.
 */
typedef struct {
    int tw;             /**< Real texture width. A power of two. */
    int th;             /**< Real texture height. A power of two. */
    int w;              /**< Texture width, as seen when drawing. */
    int h;              /**< Texture height, as seen when drawing. */
    float ratio;        /**< Width/height ratio. */
    bool swizzled;      /**< Is the texture swizzled ? */
    g2dColor *data;     /**< Pointer to raw data. */
} g2dTexture;

/**
 * \var g2d_draw_buffer
 * \brief The current draw buffer as a texture.
 */
/**
 * \var g2d_disp_buffer
 * \brief The current display buffer as a texture.
 */
extern g2dTexture g2d_draw_buffer;
extern g2dTexture g2d_disp_buffer;

/**
 * \brief Initializes the library.
 *
 * This function will create a GU context and setup the display buffers.
 * Automatically called by the other functions.
 */
void g2dInit(void);

/**
 * \brief Shutdowns the library.
 *
 * This function will destroy the GU context.
 */
void g2dTerm(void);

/**
 * \brief Clears screen & depth buffer.
 * @param color Screen clear color
 *
 * This function clears the screen, and clears the zbuffer if depth coordinate
 * is used in the loop. Will automatically init the GU if needed.
 */
void g2dClear(g2dColor color);

/**
 * \brief Clears depth buffer.
 *
 * This function clears the zbuffer to zero (z range 0-65535).
 * Will automatically init the GU if needed.
 */
void g2dClearZ(void);

/**
 * \brief Begins rectangles rendering.
 * @param tex Pointer to a texture, pass NULL to get a colored rectangle.
 *
 * This function begins object rendering. Resets all properties.
 * One g2dAdd() call per object.
 * Only one texture can be used, but multiple objects can be rendered at a time.
 * g2dBegin*() / g2dEnd() couple can be called multiple times in the loop,
 * to render multiple textures.
 */
void g2dBeginRects(g2dTexture *tex);

/**
 * \brief Begins lines rendering.
 * @param line_mode A g2dLine_Mode constant.
 *
 * This function begins object rendering. Calls g2dReset().
 * Two g2dAdd() calls per object.
 * Pass G2D_LINE_STRIP to make a line strip (two calls, then one per object).
 */
void g2dBeginLines(g2dLine_Mode mode);

/**
 * \brief Begins quads rendering.
 * @param tex Pointer to a texture, pass NULL to get a colored quad.
 *
 * This function begins object rendering. Resets all properties.
 * Four g2dAdd() calls per object, first for the up left corner, then clockwise.
 * Only one texture can be used, but multiple objects can be rendered at a time.
 * g2dBegin*() / g2dEnd() couple can be called multiple times in the loop,
 * to render multiple textures.
 */
void g2dBeginQuads(g2dTexture *tex);

/**
 * \brief Begins points rendering.
 *
 * This function begins object rendering. Resets all properties.
 * One g2dAdd() call per object.
 */
void g2dBeginPoints(void);

/**
 * \brief Ends object rendering.
 *
 * This function ends object rendering. Must be called after g2dBegin*() to add
 * objects to the display list. Automatically adapts pspgu functionnalities
 * to get the best performance possible.
 */
void g2dEnd(void);

/**
 * \brief Resets current transformation and attribution.
 *
 * This function must be called during object rendering.
 * Calls g2dResetCoord(), g2dResetRotation(), g2dResetScale(),
 * g2dResetColor(), g2dResetAlpha(), g2dResetCrop() and g2dResetTex().
 */
void g2dReset(void);

/**
 * \brief Flips the screen.
 * @param flip_mode A g2dFlip_Mode constant.
 *
 * This function must be called at the end of the loop.
 * Renders the whole display list to the draw buffer.
 * Inverts framebuffers to display the whole thing.
 */
void g2dFlip(g2dFlip_Mode mode);

/**
 * \brief Pushes the current transformation & attribution to a new object.
 *
 * This function must be called during object rendering.
 */
void g2dAdd(void);

/**
 * \brief Saves the current transformation to stack.
 *
 * This function must be called during object rendering.
 * The stack is 64 saves high.
 * Use it like the OpenGL one.
 */
void g2dPush(void);

/**
 * \brief Restore the current transformation from stack.
 *
 * This function must be called during object rendering.
 * The stack is 64 saves high.
 * Use it like the OpenGL one.
 */
void g2dPop(void);

/**
 * \brief Creates a new blank texture.
 * @param w Width of the texture.
 * @param h Height of the texture.
 *
 * This function returns NULL on allocation fail.
 */
g2dTexture* g2dTexCreate(int w, int h);

/**
 * \brief Frees a texture & set its pointer to NULL.
 * @param tex Pointer to the variable which contains the texture pointer.
 *
 * This function is used to gain memory when a texture is useless.
 * Must pass the pointer to the variable which contains the pointer,
 * to set it to NULL (passing NULL to a g2dBegin* function is safe).
 */
void g2dTexFree(g2dTexture **tex);

/**
 * \brief Loads an image.
 * @param data RGBA texture buffer.
 * @param width Texture width.
 * @param height Texture height.
 * @param tex_mode A g2dTex_Mode constant.
 * @returns Pointer to the generated texture.
 *
 * Swizzling is enabled only for 16*16+ textures (useless on small textures), pass G2D_SWIZZLE to enable it.
 * Texture supported up to 512*512 in size only (hardware limitation).
 */
g2dTexture *g2dTexLoad(void *data, int width, int height, g2dTex_Mode mode);

/**
 * \brief Resets the current coordinates.
 *
 * This function must be called during object rendering.
 * Sets g2dSetCoordMode() to G2D_UP_LEFT and g2dSetCoordXYZ() to (0,0,0).
 */
void g2dResetCoord(void);

/**
 * \brief Set coordinate mode.
 * @param coord_mode A gCoord_Mode.
 *
 * This function must be called during object rendering.
 * Defines where the coordinates correspond in the object.
 */
void g2dSetCoordMode(g2dCoord_Mode mode);

/**
 * \brief Gets the current position.
 * @param x Pointer to save the current x (in pixels).
 * @param y Pointer to save the current y (in pixels).
 * @param z Pointer to save the current z (in pixels).
 *
 * This function must be called during object rendering.
 * Parameters are pointers to float, not int !
 * Pass NULL if not needed.
 */
void g2dGetCoordXYZ(float *x, float *y, float *z);

/**
 * \brief Sets the new position.
 * @param x New x, in pixels.
 * @param y New y, in pixels.
 *
 * This function must be called during object rendering.
 */
void g2dSetCoordXY(float x, float y);

/**
 * \brief Sets the new position, with depth support.
 * @param x New x, in pixels.
 * @param y New y, in pixels.
 * @param z New z, in pixels. (front 0-65535 back)
 *
 * This function must be called during object rendering.
 */
void g2dSetCoordXYZ(float x, float y, float z);

/**
 * \brief Sets the new position, relative to the current.
 * @param x New x increment, in pixels.
 * @param y New y increment, in pixels.
 *
 * This function must be called during object rendering.
 */
void g2dSetCoordXYRelative(float x, float y);

/**
 * \brief Sets the new position, with depth support, relative to the current.
 * @param x New x increment, in pixels.
 * @param y New y increment, in pixels.
 * @param z New z increment, in pixels.
 *
 * This function must be called during object rendering.
 */
void g2dSetCoordXYZRelative(float x, float y, float z);

/**
 * \brief Use integer coordinates.
 * @param use false to desactivate (better look, by default),
                            true to activate (can be useful when you have glitches).
 *
 * This function must be called during object rendering.
 */
void g2dSetCoordInteger(bool use);

/**
 * \brief Resets the global scale.
 *
 * This function resets the global scale to 1.f.
 * Translations and scales are multiplied by this factor.
 */
void g2dResetGlobalScale(void);

/**
 * \brief Resets the current scale.
 *
 * This function must be called during object rendering.
 * Sets the scale to the current texture size or (10,10).
 */
void g2dResetScale(void);

/**
 * \brief Gets the global scale.
 * @param scale Pointer to save the global scale (factor).
 *
 * Pass NULL if not needed.
 */
void g2dGetGlobalScale(float *scale);

/**
 * \brief Gets the current scale.
 * @param w Pointer to save the current width (in pixels).
 * @param h Pointer to save the current height (in pixels).
 *
 * This function must be called during object rendering.
 * Parameters are pointers to float, not int !
 * Pass NULL if not needed.
 */
void g2dGetScaleWH(float *w, float *h);

/**
 * \brief Sets the global scale.
 *
 * Translations and scales are multiplied by this factor.
 */
void g2dSetGlobalScale(float scale);

/**
 * \brief Sets the new scale.
 * @param w Width scale factor.
 * @param h Height scale factor.
 *
 * This function must be called during object rendering.
 * g2dResetScale() is called, then width & height scale are
 * multiplied by these values.
 * Negative values can be passed to invert the texture.
 */
void g2dSetScale(float w, float h);

/**
 * \brief Sets the new scale, in pixels.
 * @param w New width, in pixels.
 * @param h New height, in pixels.
 *
 * This function must be called during object rendering.
 * Negative values can be passed to invert the texture.
 */
void g2dSetScaleWH(float w, float h);

/**
 * \brief Sets the new scale, relative to the current.
 * @param w Width scale factor.
 * @param h Height scale factor.
 *
 * This function must be called during object rendering.
 * Current width & height scale are multiplied by these values.
 * Negative values can be passed to invert the texture.
 */
void g2dSetScaleRelative(float w, float h);

/**
 * \brief Sets the new scale, in pixels, relative to the current.
 * @param w New width to increment, in pixels.
 * @param h New height to increment, in pixels.
 *
 * This function must be called during object rendering.
 * Negative values can be passed to invert the texture.
 */
void g2dSetScaleWHRelative(float w, float h);

/**
 * \brief Resets the current color.
 *
 * This function must be called during object rendering.
 * Sets g2dSetColor() to WHITE.
 */
void g2dResetColor(void);

/**
 * \brief Resets the current alpha.
 *
 * This function must be called during object rendering.
 * Sets g2dSetAlpha() to 255.
 */
void g2dResetAlpha(void);

/**
 * \brief Gets the current alpha.
 * @param alpha Pointer to save the current alpha (0-255).
 *
 * This function must be called during object rendering.
 * Pass NULL if not needed.
 */
void g2dGetAlpha(g2dAlpha *alpha);

/**
 * \brief Sets the new color.
 * @param color The new color.
 *
 * This function must be called during object rendering.
 * Can be used to colorize any object.
 */
void g2dSetColor(g2dColor color);

/**
 * \brief Sets the new alpha.
 * @param alpha The new alpha (0-255).
 *
 * This function must be called during object rendering.
 * Can be used to make any object transparent.
 */
void g2dSetAlpha(g2dAlpha alpha);

/**
 * \brief Sets the new alpha, relative to the current alpha.
 * @param alpha The new alpha increment.
 *
 * This function must be called during object rendering.
 * Can be used to make any object transparent.
 */
void g2dSetAlphaRelative(int alpha);

/**
 * \brief Resets the current rotation.
 *
 * This function must be called during object rendering.
 * Sets g2dSetRotation() to 0°.
 */
void g2dResetRotation(void);

/**
 * \brief Gets the current rotation, in radians.
 * @param radians Pointer to save the current rotation.
 *
 * This function must be called during object rendering.
 * Pass NULL if not needed.
 */
void g2dGetRotationRad(float *radians);

/**
 * \brief Gets the current rotation, in degrees.
 * @param degrees Pointer to save the current rotation.
 *
 * This function must be called during object rendering.
 * Pass NULL if not needed.
 */
void g2dGetRotation(float *degrees);

/**
 * \brief Sets the new rotation, in radians.
 * @param radians The new angle.
 *
 * This function must be called during object rendering.
 * The rotation center is the actual coordinates.
 */
void g2dSetRotationRad(float radians);

/**
 * \brief Sets the new rotation, in degrees.
 * @param degrees The new angle.
 *
 * This function must be called during object rendering.
 * The rotation center is the actual coordinates.
 */
void g2dSetRotation(float degrees);

/**
 * \brief Sets the new rotation, relative to the current, in radians.
 * @param radians The new angle increment.
 *
 * This function must be called during object rendering.
 * The rotation center is the actual coordinates.
 */
void g2dSetRotationRadRelative(float radians);

/**
 * \brief Sets the new rotation, relative to the current, in degrees.
 * @param degrees The new angle increment.
 *
 * This function must be called during object rendering.
 * The rotation center is the actual coordinates.
 */
void g2dSetRotationRelative(float degrees);

/**
 * \brief Resets the current crop.
 *
 * This function must be called during object rendering.
 * Sets g2dSetCropXY() to (0;0) and g2dSetCropWH() to (tex->w,tex->h).
 */
void g2dResetCrop(void);

/**
 * \brief Gets the current crop position.
 * @param x Pointer to save the current crop x.
 * @param y Pointer to save the current crop y.
 *
 * This function must be called during object rendering.
 * Pass NULL if not needed.
 */
void g2dGetCropXY(int *x, int *y);

/**
 * \brief Gets the current crop scale.
 * @param w Pointer to save the current crop width.
 * @param h Pointer to save the current crop height.
 *
 * This function must be called during object rendering.
 * Pass NULL if not needed.
 */
void g2dGetCropWH(int *w, int *h);

/**
 * \brief Sets the new crop position.
 * @param x New x, in pixels.
 * @param y New y, in pixels.
 *
 * This function must be called during object rendering. Defines crop position.
 * If the rectangle is larger or next to the texture, it will be repeated
 * when g2dSetTexRepeat is enabled. Useful for a tileset.
 */
void g2dSetCropXY(int x, int y);

/**
 * \brief Sets the new crop size.
 * @param w New width, in pixels.
 * @param h New height, in pixels.
 *
 * This function must be called during object rendering. Defines crop size.
 * If the rectangle is larger or next to the texture, it will be repeated
 * when g2dSetTexRepeat is enabled. Useful for a tileset.
 */
void g2dSetCropWH(int w, int h);

/**
 * \brief Sets the new crop position, relative to the current.
 * @param x New x increment, in pixels.
 * @param y New y increment, in pixels.
 *
 * This function must be called during object rendering. Defines crop position.
 * If the rectangle is larger or next to the texture, texture will be repeated
 * when g2dSetTexRepeat is enabled. Useful for a tileset.
 */
void g2dSetCropXYRelative(int x, int y);

/**
 * \brief Sets the new crop size, relative to the current.
 * @param w New width increment, in pixels.
 * @param h New height increment, in pixels.
 *
 * This function must be called during object rendering. Defines crop size.
 * If the rectangle is larger or next to the texture, texture will be repeated
 * when g2dSetTexRepeat is enabled. Useful for a tileset.
 */
void g2dSetCropWHRelative(int w, int h);

/**
 * \brief Resets texture properties.
 *
 * This function must be called during object rendering.
 */
void g2dResetTex(void);

/**
 * \brief Set texture wrap.
 * @param use true to repeat, false to clamp (by default).
 *
 * This function must be called during object rendering.
 */
void g2dSetTexRepeat(bool use);

/**
 * \brief Use the bilinear filter with the texture.
 * @param use true to activate (better look, by default).
                            false to desactivate (better performance).
 *
 * This function must be called during object rendering.
 * Only useful when scaling.
 */
void g2dSetTexLinear(bool use);

/**
 * \brief Resets the draw zone to the entire screen.
 *
 * This function can be called everywhere in the loop.
 */
void g2dResetScissor(void);

/**
 * \brief Sets the draw zone.
 * @param x New x position.
 * @param y New y position.
 * @param w New width.
 * @param h New height.
 *
 * This function can be called everywhere in the loop.
 * Pixel draw will be skipped outside this rectangle.
 */
void g2dSetScissor(int x, int y, int w, int h);

#ifdef __cplusplus
}
#endif

#endif