local core = require "core" local common = require "core.common" local config = require "core.config" local style = require "core.style" local Object = require "core.object" ---Scrollbar ---Use Scrollbar:set_size to set the bounding box of the view the scrollbar belongs to. ---Use Scrollbar:update to update the scrollbar animations. ---Use Scrollbar:draw to draw the scrollbar. ---Use Scrollbar:on_mouse_pressed, Scrollbar:on_mouse_released, ---Scrollbar:on_mouse_moved and Scrollbar:on_mouse_left to react to mouse movements; ---the scrollbar won't update automatically. ---Use Scrollbar:set_percent to set the scrollbar location externally. --- ---To manage all the orientations, the scrollbar changes the coordinates system ---accordingly. The "normal" coordinate system adapts the scrollbar coordinates ---as if it's always a vertical scrollbar, positioned at the end of the bounding box. ---@class core.scrollbar : core.object local Scrollbar = Object:extend() ---@class ScrollbarOptions ---@field direction "v" | "h" @Vertical or Horizontal ---@field alignment "s" | "e" @Start or End (left to right, top to bottom) ---@field force_status "expanded" | "contracted" | false @Force the scrollbar status ---@field expanded_size number? @Override the default value specified by `style.expanded_scrollbar_size` ---@field contracted_size number? @Override the default value specified by `style.scrollbar_size` ---@param options ScrollbarOptions function Scrollbar:new(options) ---Position information of the owner self.rect = { x = 0, y = 0, w = 0, h = 0, ---Scrollable size scrollable = 0 } self.normal_rect = { across = 0, along = 0, across_size = 0, along_size = 0, scrollable = 0 } ---@type integer @Position in percent [0-1] self.percent = 0 ---@type boolean @Scrollbar dragging status self.dragging = false ---@type integer @Private. Used to offset the start of the drag from the top of the thumb self.drag_start_offset = 0 ---What is currently being hovered. `thumb` implies` track` self.hovering = { track = false, thumb = false } ---@type "v" | "h"@Vertical or Horizontal self.direction = options.direction or "v" ---@type "s" | "e" @Start or End (left to right, top to bottom) self.alignment = options.alignment or "e" ---@type number @Private. Used to keep track of animations self.expand_percent = 0 ---@type "expanded" | "contracted" | false @Force the scrollbar status self.force_status = options.force_status self:set_forced_status(options.force_status) ---@type number? @Override the default value specified by `style.expanded_scrollbar_size` self.contracted_size = options.contracted_size ---@type number? @Override the default value specified by `style.scrollbar_size` self.expanded_size = options.expanded_size end ---Set the status the scrollbar is forced to keep ---@param status "expanded" | "contracted" | false @The status to force function Scrollbar:set_forced_status(status) self.force_status = status if self.force_status == "expanded" then self.expand_percent = 1 end end function Scrollbar:real_to_normal(x, y, w, h) x, y, w, h = x or 0, y or 0, w or 0, h or 0 if self.direction == "v" then if self.alignment == "s" then x = (self.rect.x + self.rect.w) - x - w end return x, y, w, h else if self.alignment == "s" then y = (self.rect.y + self.rect.h) - y - h end return y, x, h, w end end function Scrollbar:normal_to_real(x, y, w, h) x, y, w, h = x or 0, y or 0, w or 0, h or 0 if self.direction == "v" then if self.alignment == "s" then x = (self.rect.x + self.rect.w) - x - w end return x, y, w, h else if self.alignment == "s" then x = (self.rect.y + self.rect.h) - x - w end return y, x, h, w end end function Scrollbar:_get_thumb_rect_normal() local nr = self.normal_rect local sz = nr.scrollable if sz == math.huge or sz <= nr.along_size then return 0, 0, 0, 0 end local scrollbar_size = self.contracted_size or style.scrollbar_size local expanded_scrollbar_size = self.expanded_size or style.expanded_scrollbar_size local along_size = math.max(20, nr.along_size * nr.along_size / sz) local across_size = scrollbar_size across_size = across_size + (expanded_scrollbar_size - scrollbar_size) * self.expand_percent return nr.across + nr.across_size - across_size, nr.along + self.percent * (nr.along_size - along_size), across_size, along_size end ---Get the thumb rect (the part of the scrollbar that can be dragged) ---@return integer,integer,integer,integer @x, y, w, h function Scrollbar:get_thumb_rect() return self:normal_to_real(self:_get_thumb_rect_normal()) end function Scrollbar:_get_track_rect_normal() local nr = self.normal_rect local sz = nr.scrollable if sz <= nr.along_size or sz == math.huge then return 0, 0, 0, 0 end local scrollbar_size = self.contracted_size or style.scrollbar_size local expanded_scrollbar_size = self.expanded_size or style.expanded_scrollbar_size local across_size = scrollbar_size across_size = across_size + (expanded_scrollbar_size - scrollbar_size) * self.expand_percent return nr.across + nr.across_size - across_size, nr.along, across_size, nr.along_size end ---Get the track rect (the "background" of the scrollbar) ---@return number,number,number,number @x, y, w, h function Scrollbar:get_track_rect() return self:normal_to_real(self:_get_track_rect_normal()) end function Scrollbar:_overlaps_normal(x, y) local sx, sy, sw, sh = self:_get_thumb_rect_normal() local scrollbar_size = self.contracted_size or style.scrollbar_size local result if x >= sx - scrollbar_size * 3 and x <= sx + sw and y >= sy and y <= sy + sh then result = "thumb" else sx, sy, sw, sh = self:_get_track_rect_normal() if x >= sx - scrollbar_size * 3 and x <= sx + sw and y >= sy and y <= sy + sh then result = "track" end end return result end ---Get what part of the scrollbar the coordinates overlap ---@return "thumb"|"track"|nil function Scrollbar:overlaps(x, y) x, y = self:real_to_normal(x, y) return self:_overlaps_normal(x, y) end function Scrollbar:_on_mouse_pressed_normal(button, x, y, clicks) local overlaps = self:_overlaps_normal(x, y) if overlaps then local _, along, _, along_size = self:_get_thumb_rect_normal() self.dragging = true if overlaps == "thumb" then self.drag_start_offset = along - y return true elseif overlaps == "track" then local nr = self.normal_rect self.drag_start_offset = - along_size / 2 return common.clamp((y - nr.along - along_size / 2) / (nr.along_size - along_size), 0, 1) end end end ---Updates the scrollbar with mouse pressed info. ---Won't update the scrollbar position automatically. ---Use Scrollbar:set_percent to update it. --- ---This sets the dragging status if needed. --- ---Returns a falsy value if the event happened outside the scrollbar. ---Returns `true` if the thumb was pressed. ---If the track was pressed this returns a value between 0 and 1 ---representing the percent of the position. ---@return boolean|number function Scrollbar:on_mouse_pressed(button, x, y, clicks) if button ~= "left" then return end x, y = self:real_to_normal(x, y) return self:_on_mouse_pressed_normal(button, x, y, clicks) end ---Updates the scrollbar hover status. ---This gets called by other functions and shouldn't be called manually function Scrollbar:_update_hover_status_normal(x, y) local overlaps = self:_overlaps_normal(x, y) self.hovering.thumb = overlaps == "thumb" self.hovering.track = self.hovering.thumb or overlaps == "track" return self.hovering.track or self.hovering.thumb end function Scrollbar:_on_mouse_released_normal(button, x, y) self.dragging = false return self:_update_hover_status_normal(x, y) end ---Updates the scrollbar dragging status function Scrollbar:on_mouse_released(button, x, y) if button ~= "left" then return end x, y = self:real_to_normal(x, y) return self:_on_mouse_released_normal(button, x, y) end function Scrollbar:_on_mouse_moved_normal(x, y, dx, dy) if self.dragging then local nr = self.normal_rect local _, _, _, along_size = self:_get_thumb_rect_normal() return common.clamp((y - nr.along + self.drag_start_offset) / (nr.along_size - along_size), 0, 1) end return self:_update_hover_status_normal(x, y) end ---Updates the scrollbar with mouse moved info. ---Won't update the scrollbar position automatically. ---Use Scrollbar:set_percent to update it. --- ---This updates the hovering status. --- ---Returns a falsy value if the event happened outside the scrollbar. ---Returns `true` if the scrollbar is hovered. ---If the scrollbar was being dragged, this returns a value between 0 and 1 ---representing the percent of the position. ---@return boolean|number function Scrollbar:on_mouse_moved(x, y, dx, dy) x, y = self:real_to_normal(x, y) dx, dy = self:real_to_normal(dx, dy) -- TODO: do we need this? (is this even correct?) return self:_on_mouse_moved_normal(x, y, dx, dy) end ---Updates the scrollbar hovering status function Scrollbar:on_mouse_left() self.hovering.track, self.hovering.thumb = false, false end ---Updates the bounding box of the view the scrollbar belongs to. ---@param x number ---@param y number ---@param w number ---@param h number ---@param scrollable number @size of the scrollable area function Scrollbar:set_size(x, y, w, h, scrollable) self.rect.x, self.rect.y, self.rect.w, self.rect.h = x, y, w, h self.rect.scrollable = scrollable local nr = self.normal_rect nr.across, nr.along, nr.across_size, nr.along_size = self:real_to_normal(x, y, w, h) nr.scrollable = scrollable end ---Updates the scrollbar location ---@param percent number @number between 0 and 1 where 0 means thumb at the top and 1 at the bottom function Scrollbar:set_percent(percent) self.percent = percent end ---Updates the scrollbar animations function Scrollbar:update() -- TODO: move the animation code to its own class if not self.force_status then local dest = (self.hovering.track or self.dragging) and 1 or 0 local diff = math.abs(self.expand_percent - dest) if not config.transitions or diff < 0.05 or config.disabled_transitions["scroll"] then self.expand_percent = dest else local rate = 0.3 if config.fps ~= 60 or config.animation_rate ~= 1 then local dt = 60 / config.fps rate = 1 - common.clamp(1 - rate, 1e-8, 1 - 1e-8)^(config.animation_rate * dt) end self.expand_percent = common.lerp(self.expand_percent, dest, rate) end if diff > 1e-8 then core.redraw = true end elseif self.force_status == "expanded" then self.expand_percent = 1 elseif self.force_status == "contracted" then self.expand_percent = 0 end end ---Draw the scrollbar track function Scrollbar:draw_track() if not (self.hovering.track or self.dragging) and self.expand_percent == 0 then return end local color = { table.unpack(style.scrollbar_track) } color[4] = color[4] * self.expand_percent local x, y, w, h = self:get_track_rect() renderer.draw_rect(x, y, w, h, color) end ---Draw the scrollbar thumb function Scrollbar:draw_thumb() local highlight = self.hovering.thumb or self.dragging local color = highlight and style.scrollbar2 or style.scrollbar local x, y, w, h = self:get_thumb_rect() renderer.draw_rect(x, y, w, h, color) end ---Draw both the scrollbar track and thumb function Scrollbar:draw() self:draw_track() self:draw_thumb() end return Scrollbar