6 ex__gui__hover_8c
gullradriel edited this page 2026-10-09 00:55:18 +02:00

examples/ex_gui_hover.c

Functions

Name
int process_args(int argc, char ** argv)
void on_click(int widget_id, void * user_data)
void move_to(N_GUI_CTX * gui, int x, int y)
ALLEGRO_EVENT mouse_event(int type, int x, int y)
int main(int argc, char ** argv)
void expect_true(const char * label, int cond)

Attributes

Name
int log_level
int failures

Defines

Name
ALLEGRO_UNSTABLE

Functions Documentation

function process_args

static int process_args(
    int argc,
    char ** argv
)

function on_click

static void on_click(
    int widget_id,
    void * user_data
)

function move_to

static void move_to(
    N_GUI_CTX * gui,
    int x,
    int y
)

function mouse_event

static ALLEGRO_EVENT mouse_event(
    int type,
    int x,
    int y
)

function main

int main(
    int argc,
    char ** argv
)

function expect_true

static void expect_true(
    const char * label,
    int cond
)

Attributes Documentation

variable log_level

static int log_level = 3;

variable failures

static int failures = 0;

Macros Documentation

define ALLEGRO_UNSTABLE

#define ALLEGRO_UNSTABLE 1

Source code

/*
 * Nilorea Library
 * Copyright (C) 2005-2026 Castagnier Mickael
 *
 * 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.
 *
 * SPDX-License-Identifier: Apache-2.0
 */


#define ALLEGRO_UNSTABLE 1

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include "nilorea/n_common.h"
#include "nilorea/n_log.h"
#include "nilorea/n_gui.h"

static int log_level = LOG_ERR;
static int failures = 0;

static void expect_true(const char* label, int cond) {
    if (!cond) {
        n_log(LOG_ERR, "%s: condition false", label);
        failures++;
    } else {
        n_log(LOG_INFO, "%s: OK", label);
    }
}

static void on_click(int widget_id, void* user_data) {
    (void)widget_id;
    (void)user_data;
}

static int process_args(int argc, char** argv) {
    int opt;
    while ((opt = getopt(argc, argv, "V:")) != -1) {
        switch (opt) {
            case 'V':
                if (!strcmp("LOG_NULL", optarg))
                    log_level = LOG_NULL;
                else if (!strcmp("LOG_NOTICE", optarg))
                    log_level = LOG_NOTICE;
                else if (!strcmp("LOG_INFO", optarg))
                    log_level = LOG_INFO;
                else if (!strcmp("LOG_ERR", optarg))
                    log_level = LOG_ERR;
                else if (!strcmp("LOG_DEBUG", optarg))
                    log_level = LOG_DEBUG;
                else
                    return -1;
                break;
            default:
                return -1;
        }
    }
    return 0;
}

/* Build a mouse event at (x, y). */
static ALLEGRO_EVENT mouse_event(int type, int x, int y) {
    ALLEGRO_EVENT ev;
    memset(&ev, 0, sizeof(ev));
    ev.type = (unsigned int)type;
    ev.mouse.x = x;
    ev.mouse.y = y;
    ev.mouse.button = 1;
    return ev;
}

static void move_to(N_GUI_CTX* gui, int x, int y) {
    ALLEGRO_EVENT ev = mouse_event(ALLEGRO_EVENT_MOUSE_AXES, x, y);
    n_gui_process_event(gui, ev);
}

int main(int argc, char** argv) {
    set_log_level(LOG_ERR);
    if (process_args(argc, argv) != 0) {
        fprintf(stderr, "Usage: %s [-V LOG_LEVEL]\n", argv[0]);
        return 2;
    }
    set_log_level(log_level);

    if (!al_init()) {
        n_log(LOG_ERR, "al_init failed");
        return 1;
    }
    if (!al_init_font_addon()) {
        n_log(LOG_ERR, "al_init_font_addon failed");
        return 1;
    }
    /* Builtin font does not need a display. */
    ALLEGRO_FONT* font = al_create_builtin_font();
    if (!font) {
        n_log(LOG_ERR, "al_create_builtin_font failed");
        return 1;
    }

    N_GUI_CTX* gui = n_gui_new_ctx(font);
    if (!gui) {
        n_log(LOG_ERR, "n_gui_new_ctx failed");
        al_destroy_font(font);
        return 1;
    }
    n_gui_set_display_size(gui, 800.0f, 600.0f);

    expect_true("no hover before any event", n_gui_hovered_widget(gui) == -1);

    /* Window A (frameless: widget screen coords == window coords) with a
       button at (10,10,80,30) and a label at (10,60,80,20). */
    int win_a = n_gui_add_window(gui, "A", 0.0f, 0.0f, 200.0f, 150.0f);
    n_gui_window_set_flags(gui, win_a, N_GUI_WIN_FRAMELESS);
    int btn = n_gui_add_button(gui, win_a, "Go", 10.0f, 10.0f, 80.0f, 30.0f, N_GUI_SHAPE_ROUNDED, on_click, NULL);
    int lbl = n_gui_add_label(gui, win_a, "text", 10.0f, 60.0f, 80.0f, 20.0f, N_GUI_ALIGN_LEFT);
    n_gui_open_window(gui, win_a);

    expect_true("window + widgets created", win_a >= 0 && btn >= 0 && lbl >= 0);

    move_to(gui, 50, 25);
    expect_true("button hovered under pointer", n_gui_hovered_widget(gui) == btn);
    {
        const N_GUI_WIDGET* w = n_gui_get_widget(gui, n_gui_hovered_widget(gui));
        expect_true("hovered widget type is BUTTON", w && w->type == N_GUI_TYPE_BUTTON);
    }

    move_to(gui, 50, 70);
    expect_true("label hovered under pointer", n_gui_hovered_widget(gui) == lbl);

    move_to(gui, 150, 140);
    expect_true("empty window space hovers nothing", n_gui_hovered_widget(gui) == -1);

    /* ACTIVE during a press still reports the widget (the pointer is on it). */
    move_to(gui, 50, 25);
    {
        ALLEGRO_EVENT down = mouse_event(ALLEGRO_EVENT_MOUSE_BUTTON_DOWN, 50, 25);
        n_gui_process_event(gui, down);
        expect_true("pressed button still reported", n_gui_hovered_widget(gui) == btn);
        ALLEGRO_EVENT up = mouse_event(ALLEGRO_EVENT_MOUSE_BUTTON_UP, 50, 25);
        n_gui_process_event(gui, up);
    }

    /* An invisible widget is skipped even if a stale flag were left set. */
    n_gui_set_widget_visible(gui, btn, 0);
    move_to(gui, 50, 25);
    expect_true("invisible widget not reported", n_gui_hovered_widget(gui) != btn);
    n_gui_set_widget_visible(gui, btn, 1);

    /* Window B overlaps A and sits later in z-order (front-most): its widget
       wins the hit test, and the query must report it, not A's. */
    int win_b = n_gui_add_window(gui, "B", 0.0f, 0.0f, 200.0f, 150.0f);
    n_gui_window_set_flags(gui, win_b, N_GUI_WIN_FRAMELESS);
    int btn_b = n_gui_add_button(gui, win_b, "Top", 10.0f, 10.0f, 80.0f, 30.0f, N_GUI_SHAPE_ROUNDED, on_click, NULL);
    n_gui_open_window(gui, win_b);
    n_gui_raise_window(gui, win_b);
    move_to(gui, 50, 25);
    expect_true("front-most window's widget wins", n_gui_hovered_widget(gui) == btn_b);

    /* Closing the front window hands hover back to the one behind. */
    n_gui_close_window(gui, win_b);
    move_to(gui, 50, 25);
    expect_true("closed window skipped, back window hovers", n_gui_hovered_widget(gui) == btn);

    n_gui_destroy_ctx(&gui);
    al_destroy_font(font);

    if (failures) {
        fprintf(stderr, "ex_gui_hover: %d failure(s)\n", failures);
        return 1;
    }
    printf("ex_gui_hover: all checks passed\n");
    return 0;
}