gf_gui.c

#define GF_EXPOSE_GUI
#define GF_EXPOSE_DRAW
#define GF_EXPOSE_INPUT
 
#include <gf_pre.h>
 
/* External library */
 
/* Interface */
#include <gf_gui.h>
 
/* Engine */
#include <gf_graphic.h>
#include <gf_draw.h>
#include <gf_log.h>
 
/* Standard */
#include <stdlib.h>
#include <string.h>
 
const double gf_gui_border_width = 2;
 
gf_graphic_color_t gf_gui_base_color;
gf_graphic_color_t gf_gui_font_color;
 
gf_gui_t* gf_gui_create(gf_engine_t* engine, gf_draw_t* draw) {
        gf_gui_t*   gui = malloc(sizeof(*gui));
        gf_gui_id_t i;
        memset(gui, 0, sizeof(*gui));
        gui->engine = engine;
        gui->draw   = draw;
 
        gui->pressed = -1;
 
        GF_SET_COLOR(gf_gui_base_color, 48, 96, 48, 255);
        GF_SET_COLOR(gf_gui_font_color, 256 - 32, 256 - 32, 256 - 32, 255);
 
        for(i = 0; i < GF_GUI_MAX_COMPONENTS; i++) gui->area[i].type = -1;
 
        return gui;
}
 
/* note... left top should be the lightest in the border */
 
void gf_gui_draw_box(gf_gui_t* gui, int mul, double x, double y, double w, double h) {
        const int          color_diff = 32; /* color diff */
        gf_graphic_color_t col;
 
        int cd = mul * color_diff;
 
        col = gf_gui_base_color;
        col.r += cd;
        col.g += cd;
        col.b += cd;
        gf_graphic_fill_rect(gui->draw, x, y, w, h, col);
 
        col = gf_gui_base_color;
        col.r -= cd;
        col.g -= cd;
        col.b -= cd;
        gf_graphic_fill_polygon(gui->draw, col, GF_GRAPHIC_2D, 5, x + w, y + h, x + w, y, x + w - gf_gui_border_width, y + gf_gui_border_width, x + gf_gui_border_width, y + h - gf_gui_border_width, x, y + h);
 
        col = gf_gui_base_color;
        gf_graphic_fill_rect(gui->draw, x + gf_gui_border_width, y + gf_gui_border_width, w - gf_gui_border_width * 2, h - gf_gui_border_width * 2, col);
}
 
gf_gui_component_t* gf_gui_first_unused(gf_gui_t* gui, gf_gui_id_t* id) {
        gf_gui_id_t i;
        for(i = 0; i < GF_GUI_MAX_COMPONENTS; i++) {
                if(gui->area[i].type == GF_GUI_UNUSED) {
                        *id = i;
                        return &gui->area[i];
                }
        }
        return NULL;
}
 
gf_gui_id_t gf_gui_create_button(gf_gui_t* gui, double x, double y, double w, double h, const char* text) {
        gf_gui_id_t         id;
        gf_gui_component_t* c = gf_gui_first_unused(gui, &id);
 
        c->type   = GF_GUI_BUTTON;
        c->x      = x;
        c->y      = y;
        c->width  = w;
        c->height = h;
 
        c->pressed  = 0;
        c->callback = NULL;
 
        c->u.button.text = malloc(strlen(text) + 1);
        strcpy(c->u.button.text, text);
        return id;
}
 
void gf_gui_render(gf_gui_t* gui) {
        gf_gui_id_t i;
        gf_input_t* input = gui->draw->input;
        for(i = GF_GUI_MAX_COMPONENTS - 1; i >= 0; i--) {
                gf_gui_component_t* c  = &gui->area[i];
                double              cx = c->x;
                double              cy = c->y;
                double              cw = c->width;
                double              ch = c->height;
                switch(c->type) {
                case GF_GUI_BUTTON: {
                        if(input->mouse_x != -1 && input->mouse_y != -1 && gui->pressed == -1 && (input->mouse_flag & GF_INPUT_MOUSE_LEFT_MASK) && (cx <= input->mouse_x && input->mouse_x <= cx + cw) && (cy <= input->mouse_y && input->mouse_y <= cy + ch)) {
                                gui->pressed = i;
                        } else if(gui->pressed == -1) {
                                c->pressed = 0;
                        }
                        break;
                }
                }
        }
        for(i = 0; i < GF_GUI_MAX_COMPONENTS; i++) {
                gf_gui_component_t* c  = &gui->area[i];
                double              cx = c->x;
                double              cy = c->y;
                double              cw = c->width;
                double              ch = c->height;
                switch(c->type) {
                case GF_GUI_BUTTON: {
                        double x = cx + cw / 2 - gf_graphic_text_width(gui->draw, GF_GUI_FONT_SIZE, c->u.button.text) / 2;
                        double y = cy + ch / 2 - GF_GUI_FONT_SIZE / 2;
                        if(gui->pressed == i) {
                                x += gf_gui_border_width / 1;
                                y += gf_gui_border_width / 1;
                        }
                        gf_gui_draw_box(gui, (gui->pressed == i) ? GF_GUI_INVERT : GF_GUI_NORMAL, cx, cy, cw, ch);
                        gf_graphic_text(gui->draw, x, y, GF_GUI_FONT_SIZE, c->u.button.text, gf_gui_font_color);
                        break;
                }
                }
        }
        if((gui->pressed != -1) && !(input->mouse_flag & GF_INPUT_MOUSE_LEFT_MASK)) {
                if(gui->area[gui->pressed].callback != NULL) {
                        gui->area[gui->pressed].callback(gui->engine, gui->draw, gui->pressed, GF_GUI_PRESS_EVENT);
                }
                gui->area[gui->pressed].pressed = 1;
                gui->pressed                    = -1;
        }
}
 
void gf_gui_set_callback(gf_gui_t* gui, gf_gui_id_t id, gf_gui_callback_t callback) { gui->area[id].callback = callback; }