fluffl 0.0.5

A cross-platform multimedia layer that exposes opengl,sockets,and audio utilities for desktop and browser
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284

use super::*;

pub fn mousedown<State>() -> ListenerCallBack<State> {
    Box::new(|info| {
        let root_key = info.key;
        let gui_component_tree = info.gui_comp_tree;
        let mouse_pos = info.event.mouse_pos();

        let mouse_percentages =
            compute_scrollbar_percentages(gui_component_tree, root_key, mouse_pos);

        let (has_clicked_on_horizontal, has_clicked_on_vertical, percentages) = {
            let frame = get_frame_mut(gui_component_tree, root_key);
            let hsa = frame.horizontal_scroll_area;
            let vsa = frame.vertical_scroll_area;
            let percentages = frame.percentages;

            let has_clicked_on_horizontal = hsa.is_point_inside(mouse_pos)
                && frame
                    .rails
                    .map(|r| r.can_draw_horizontal())
                    .unwrap_or_default();
            let has_clicked_on_vertical = vsa.is_point_inside(mouse_pos)
                && frame
                    .rails
                    .map(|r| r.can_draw_vertical())
                    .unwrap_or_default();

            (
                has_clicked_on_horizontal,
                has_clicked_on_vertical,
                percentages,
            )
        };
        // println!(
        //     "hsa:[{}|{}]",
        //     horizontal_scroll_area.min_pos,
        //     horizontal_scroll_area.dims()
        // );
        // println!(
        //     "vsa:[{}|{}]",
        //     vertical_scroll_area.min_pos,
        //     vertical_scroll_area.dims()
        // );

        if has_clicked_on_horizontal {
            {
                let frame = get_frame_mut(gui_component_tree, root_key);
                frame.focused_scrollbar = FocusedScrollBarKind::Horizontal;
            }
            scroll_elements(
                gui_component_tree,
                root_key,
                Vec2::from([mouse_percentages.x(), percentages.y()]),
            );
        } else if has_clicked_on_vertical {
            {
                let frame = get_frame_mut(gui_component_tree, root_key);
                frame.focused_scrollbar = FocusedScrollBarKind::Vertical;
            }
            scroll_elements(
                gui_component_tree,
                root_key,
                Vec2::from([percentages.x(), mouse_percentages.y()]),
            );
        } else {
            {
                let frame = get_frame_mut(gui_component_tree, root_key);
                frame.focused_scrollbar = FocusedScrollBarKind::Nothing;
            }
        }
        None
    })
}

pub fn mouseup<State>() -> ListenerCallBack<State> {
    Box::new(|info| {
        let root_key = info.key;
        let gui_component_tree = info.gui_comp_tree;
        let frame = get_frame_mut(gui_component_tree, root_key);
        frame.focused_scrollbar = FocusedScrollBarKind::Nothing;
        None
    })
}

pub fn mousemove<State>() -> ListenerCallBack<State> {
    Box::new(|info| {
        let root_key = info.key;
        let gui_component_tree = info.gui_comp_tree;
        let mouse_pos = info.event.mouse_pos();
        let frame = get_frame_mut(gui_component_tree, root_key);
        frame.last_known_mouse_pos = mouse_pos;
        None
    })
}

pub fn wheel<State>() -> ListenerCallBack<State> {
    Box::new(|info| {
        let root_key = info.key;
        let gui_component_tree = info.gui_comp_tree;

        resize_component_bounds_if_needed(gui_component_tree, root_key);

        let frame = get_frame_mut(gui_component_tree, root_key);
        let wheel = info.event.wheel() * 0.125;
        let horizontal_scroll_area = frame.horizontal_scroll_area;
        let can_update_horizontal =
            horizontal_scroll_area.is_point_inside(frame.last_known_mouse_pos);

        if can_update_horizontal {
            frame.percentages[0] += wheel;
            frame.percentages[0] = frame.percentages[0].clamp(0.0, 1.0);
            let uv = frame.percentages;
            scroll_elements(gui_component_tree, root_key, uv);
        } else {
            frame.percentages[1] += -wheel;
            frame.percentages[1] = frame.percentages[1].clamp(0.0, 1.0);
            let uv = frame.percentages;
            scroll_elements(gui_component_tree, root_key, uv);
        }

        None
    })
}
pub fn drag<State>() -> ListenerCallBack<State> {
    Box::new(|info| {
        let root_key = info.key;
        let gui_component_tree = info.gui_comp_tree;
        resize_component_bounds_if_needed(gui_component_tree, root_key);

        let mouse_pos = info.event.mouse_pos();

        let mouse_uv = compute_scrollbar_percentages(gui_component_tree, root_key, mouse_pos);

        let uv = {
            let frame = get_frame_mut(gui_component_tree, root_key);

            frame.percentages
        };

        let frame = get_frame_mut(gui_component_tree, root_key);
        let focused_scrollbar = frame.focused_scrollbar;

        let can_update_horizontal = focused_scrollbar == FocusedScrollBarKind::Horizontal;
        let can_update_vertical = focused_scrollbar == FocusedScrollBarKind::Vertical;

        if can_update_horizontal {
            scroll_elements(
                gui_component_tree,
                root_key,
                Vec2::from([mouse_uv.x(), uv.y()]),
            );
        } else if can_update_vertical {
            scroll_elements(
                gui_component_tree,
                root_key,
                Vec2::from([uv.x(), mouse_uv.y()]),
            );
        }

        None
    })
}

fn get_frame(tree: &LinearTree<Box<dyn GuiComponent>>, key: GuiComponentKey) -> &FrameState {
    tree.get(key)
        .expect("root key invalid")
        .as_any()
        .downcast_ref::<FrameState>()
        .expect("node expected to be a frame")
}

fn get_frame_mut(
    tree: &mut LinearTree<Box<dyn GuiComponent>>,
    key: GuiComponentKey,
) -> &mut FrameState {
    tree.get_mut(key)
        .expect("root key invalid")
        .as_any_mut()
        .downcast_mut::<FrameState>()
        .expect("node expected to be a frame")
}

fn translate_children(
    tree: &mut LinearTree<Box<dyn GuiComponent>>,
    root_key: GuiComponentKey,
    disp: Vec2<f32>,
) {
    for NodeInfoMut { val, .. } in tree
        .iter_children_mut(root_key)
        .filter(|node| !node.val.flags().is_set(component_flags::TITLEBAR))
    {
        val.translate(disp);
    }
    let frame = get_frame_mut(tree, root_key);
    frame.camera += disp;
    frame.components_aabb.translate(disp);
}

fn scroll_elements(
    gui_component_tree: &mut LinearTree<Box<dyn GuiComponent>>,
    root_key: GuiComponentKey,
    uv: Vec2<f32>,
) {
    let frame = get_frame_mut(gui_component_tree, root_key);
    let new_min = frame.rails.unwrap().eval(uv.x(), uv.y());
    let disp = new_min - frame.components_aabb.min_pos;
    frame.percentages = uv;
    translate_children(gui_component_tree, root_key, disp)
}

fn compute_component_bounds(
    gui_component_tree: &mut LinearTree<Box<dyn GuiComponent>>,
    root_key: GuiComponentKey,
) -> AABB2<f32> {
    let mut aabb = AABB2::flipped_infinity();
    let mut executed = false;
    for NodeInfoMut { val, .. } in gui_component_tree.iter_children_mut(root_key).skip(1) {
        let &pos = val.rel_position();
        let bounds = val.bounds();
        let rel_aabb = AABB2::from_point_and_lengths(pos, bounds);
        aabb.merge(rel_aabb);
        executed = true;
    }

    if executed {
        aabb
    } else {
        AABB2::zero()
    }
}

fn resize_component_bounds_if_needed(
    gui_component_tree: &mut LinearTree<Box<dyn GuiComponent>>,
    root_key: GuiComponentKey,
) {
    let old_component_bounding_box = get_frame_mut(gui_component_tree, root_key).components_aabb;
    let new_component_bounding_box = compute_component_bounds(gui_component_tree, root_key);
    const EPSILON: f32 = 0.001;

    let component_bounding_box_changed_dramatically = !new_component_bounding_box
        .dims()
        .iter()
        .zip(old_component_bounding_box.dims().iter())
        .all(|(&cur, &prev)| (cur - prev).abs() < EPSILON);

    if component_bounding_box_changed_dramatically {
        let old_uv = get_frame_mut(gui_component_tree, root_key).percentages;
        scroll_elements(gui_component_tree, root_key, Vec2::zero());

        get_frame_mut(gui_component_tree, root_key).rails = None;
        //compute NEW AABB in the coordinate original space
        get_frame_mut(gui_component_tree, root_key).components_aabb =
            compute_component_bounds(gui_component_tree, root_key);
        get_frame_mut(gui_component_tree, root_key)
            .update_component_bounds_assuming_new_bounds_already_set();

        scroll_elements(gui_component_tree, root_key, old_uv);
    }
}

/// found the percentages have to have a low-resolution step size otherwise
/// positioning gets fucked up for some reason
/// currently percentages are in { 0.01*k | k > 0 && k < 99 }
fn compute_scrollbar_percentages(
    gui_component_tree: &mut LinearTree<Box<dyn GuiComponent>>,
    root_key: GuiComponentKey,
    mouse_pos: Vec2<f32>,
) -> Vec2<f32> {
    let frame = get_frame(gui_component_tree, root_key);
    let vertical_scroll_area = frame.vertical_scroll_area;
    let horizontal_scroll_area = frame.horizontal_scroll_area;
    let mut mouse_percentages = Vec2::from([
        (mouse_pos.x() - horizontal_scroll_area.min_pos.x())
            / (horizontal_scroll_area.dims().x() * 0.99),
        (mouse_pos.y() - vertical_scroll_area.min_pos.y())
            / (vertical_scroll_area.dims().y() * 0.99),
    ]);

    mouse_percentages
        .iter_mut()
        .for_each(|comp| *comp = (comp.clamp(0.0, 1.0) * 100.0).floor() / 100.0);
    mouse_percentages
}