Files
infinitefusion-e18/Data/Scripts/910_New anim editor/011_particle list.rb
2023-10-18 16:48:28 +01:00

640 lines
24 KiB
Ruby

#===============================================================================
# TODO: Would be nice to make command sprites wider than their viewport and
# change @commands_viewport's ox to @left_pos, similar to how the vertical
# scrollbar works, i.e. every visible @commands_sprites isn't redrawn each
# time the horizontal scrollbar changes.
#===============================================================================
class UIControls::AnimationParticleList < UIControls::BaseControl
LIST_WIDTH = 150
ROW_HEIGHT = 24
TIMELINE_HEIGHT = 24
DIAMOND_SIZE = 3
TIMELINE_LEFT_BUFFER = DIAMOND_SIZE + 1 # Allows diamonds at keyframe 0 to be drawn fully
TIMELINE_TEXT_SIZE = 16
KEYFRAME_SPACING = 20
INTERP_LINE_HEIGHT = KEYFRAME_SPACING - ((DIAMOND_SIZE * 2) + 3)
INTERP_LINE_Y = (TIMELINE_HEIGHT / 2) - (INTERP_LINE_HEIGHT / 2)
DURATION_BUFFER = 20 # Extra keyframes shown after the animation's end
CONTROL_BG_COLORS = {
:user => Color.new(96, 248, 96), # Green
:target => Color.new(248, 96, 96), # Red
:user_and_target => Color.new(248, 248, 96), # Yellow
:screen => Color.new(128, 160, 248) # Blue
}
SE_CONTROL_BG = Color.gray
attr_reader :keyframe # The selected keyframe
attr_reader :particle_index # Index in @particles
def initialize(x, y, width, height, viewport)
super(width, height, viewport)
self.x = x
self.y = y
draw_control_background
# Create viewports
@list_viewport = Viewport.new(
x, y + TIMELINE_HEIGHT, LIST_WIDTH, height - TIMELINE_HEIGHT - UIControls::Scrollbar::SLIDER_WIDTH - 1
)
@list_viewport.z = self.viewport.z + 1
@commands_bg_viewport = Viewport.new(@list_viewport.rect.x + LIST_WIDTH, @list_viewport.rect.y,
width - @list_viewport.rect.width - UIControls::Scrollbar::SLIDER_WIDTH,
@list_viewport.rect.height)
@commands_bg_viewport.z = self.viewport.z + 1
@position_viewport = Viewport.new(@list_viewport.rect.x + LIST_WIDTH, y, @commands_bg_viewport.rect.width, height)
@position_viewport.z = self.viewport.z + 2
@commands_viewport = Viewport.new(@list_viewport.rect.x + LIST_WIDTH, @list_viewport.rect.y,
width - @list_viewport.rect.width - UIControls::Scrollbar::SLIDER_WIDTH,
@list_viewport.rect.height)
@commands_viewport.z = self.viewport.z + 3
# Create scrollbar
@list_scrollbar = UIControls::Scrollbar.new(
@commands_viewport.rect.x + @commands_viewport.rect.width, @commands_viewport.rect.y,
@commands_viewport.rect.height + 1, self.viewport, false, true
)
@list_scrollbar.set_interactive_rects
@time_scrollbar = UIControls::Scrollbar.new(
@commands_viewport.rect.x, @commands_viewport.rect.y + @commands_viewport.rect.height + 1,
@commands_viewport.rect.width, self.viewport, true, true
)
@time_scrollbar.set_interactive_rects
# Timeline bitmap sprite
@timeline_sprite = BitmapSprite.new(@commands_viewport.rect.width, TIMELINE_HEIGHT, self.viewport)
@timeline_sprite.x = @commands_viewport.rect.x
@timeline_sprite.y = self.y
@timeline_sprite.bitmap.font.color = TEXT_COLOR
@timeline_sprite.bitmap.font.size = TIMELINE_TEXT_SIZE
# Position line sprite
@position_sprite = BitmapSprite.new(3, height - UIControls::Scrollbar::SLIDER_WIDTH - 1, @position_viewport)
@position_sprite.ox = @position_sprite.width / 2
@position_sprite.bitmap.fill_rect(0, 0, @position_sprite.bitmap.width, @position_sprite.bitmap.height, Color.red)
# List sprites and commands sprites
@list_sprites = []
@commands_bg_sprites = []
@commands_sprites = []
# Scrollbar positions
@left_pos = 0
@top_pos = 0
@duration = 0
# Selected things
@keyframe = 0
@particle_index = 0
# Particle information to display (one row each)
@particles = [] # Reference to particle data from the editor scene
@particle_list = [] # Each element is index in @particles or [index, property]
@visibilities = [] # Per particle
@commands = {}
end
def draw_control_background
self.bitmap.clear
# Background
self.bitmap.fill_rect(0, 0, width, height, Color.white)
# Separator lines
self.bitmap.fill_rect(0, TIMELINE_HEIGHT - 1, width, 1, Color.black)
self.bitmap.fill_rect(LIST_WIDTH - 1, 0, 1, height, Color.black)
self.bitmap.fill_rect(0, height - UIControls::Scrollbar::SLIDER_WIDTH - 1, width, 1, Color.black)
self.bitmap.fill_rect(width - UIControls::Scrollbar::SLIDER_WIDTH - 1, 0, 1, height, Color.black)
end
def dispose_listed_sprites
@list_sprites.each { |p| p&.dispose }
@list_sprites.clear
@commands_bg_sprites.each { |p| p&.dispose }
@commands_bg_sprites.clear
@commands_sprites.each { |p| p&.dispose }
@commands_sprites.clear
end
def dispose
@list_scrollbar.dispose
@time_scrollbar.dispose
@timeline_sprite.dispose
@position_sprite.dispose
dispose_listed_sprites
@list_viewport.dispose
@commands_bg_viewport.dispose
@commands_viewport.dispose
end
def left_pos=(val)
old_val = @left_pos
total_width = (@duration * KEYFRAME_SPACING) + TIMELINE_LEFT_BUFFER + 1
if total_width <= @commands_viewport.rect.width
@left_pos = 0
else
@left_pos = val
@left_pos = @left_pos.clamp(0, total_width - @commands_viewport.rect.width)
end
if @left_pos != old_val
refresh_position_line
invalidate_time
end
end
def top_pos=(val)
old_val = @top_pos
total_height = @particle_list.length * ROW_HEIGHT
if total_height <= @list_viewport.rect.height
@top_pos = 0
else
@top_pos = val
@top_pos = @top_pos.clamp(0, total_height - @list_viewport.rect.height)
end
@list_viewport.oy = @top_pos
@commands_viewport.oy = @top_pos
if @top_pos != old_val
invalidate_rows
@old_top_pos = old_val
end
end
def set_particles(particles)
@particles = particles
@particle_list.clear
calculate_all_commands_and_durations
# Dispose of and clear all existing list/commands sprites
dispose_listed_sprites
# Fill in @particle_list with indices from @particles
@particles.length.times { |i| @particle_list.push(i) }
# Create new sprites for each particle (1x list and 2x commands)
@particle_list.length.times do
list_sprite = BitmapSprite.new(@list_viewport.rect.width, ROW_HEIGHT, @list_viewport)
list_sprite.y = @list_sprites.length * ROW_HEIGHT
list_sprite.bitmap.font.color = TEXT_COLOR
list_sprite.bitmap.font.size = TEXT_SIZE
@list_sprites.push(list_sprite)
commands_bg_sprite = BitmapSprite.new(@commands_viewport.rect.width, ROW_HEIGHT, @commands_bg_viewport)
commands_bg_sprite.y = @commands_bg_sprites.length * ROW_HEIGHT
commands_bg_sprite.bitmap.font.color = TEXT_COLOR
commands_bg_sprite.bitmap.font.size = TEXT_SIZE
@commands_bg_sprites.push(commands_bg_sprite)
commands_sprite = BitmapSprite.new(@commands_viewport.rect.width, ROW_HEIGHT, @commands_viewport)
commands_sprite.y = @commands_sprites.length * ROW_HEIGHT
commands_sprite.bitmap.font.color = TEXT_COLOR
commands_sprite.bitmap.font.size = TEXT_SIZE
@commands_sprites.push(commands_sprite)
end
@list_scrollbar.range = @particle_list.length * ROW_HEIGHT
@time_scrollbar.range = (@duration * KEYFRAME_SPACING) + TIMELINE_LEFT_BUFFER + 1
self.left_pos = @left_pos
invalidate
end
def set_interactive_rects
@list_rect = Rect.new(0, TIMELINE_HEIGHT, LIST_WIDTH - 1, @list_viewport.rect.height)
@timeline_rect = Rect.new(LIST_WIDTH, 0, width - LIST_WIDTH - UIControls::Scrollbar::SLIDER_WIDTH - 1, TIMELINE_HEIGHT - 1)
@commands_rect = Rect.new(LIST_WIDTH, TIMELINE_HEIGHT, @timeline_rect.width, @list_rect.height)
@interactions = {
:list => @list_rect,
:timeline => @timeline_rect,
:commands => @commands_rect
}
end
#-----------------------------------------------------------------------------
def invalid?
return @invalid || @invalid_time || @invalid_rows || @invalid_commands
end
def invalidate_time
@invalid_time = true
end
def invalidate_rows
@invalid_rows = true
end
def invalidate_commands
@invalid_commands = true
end
def validate
super
@invalid_time = false
@invalid_rows = false
@invalid_commands = false
end
#-----------------------------------------------------------------------------
def calculate_duration
@duration = AnimationEditor::ParticleDataHelper.get_duration(@particles)
@duration += DURATION_BUFFER
end
# TODO: Call this only from set_particles and when changes are made to
# @particles by the main editor scene. If we can be specific about which
# particle was changed, recalculate only that particle's commands.
def calculate_all_commands_and_durations
calculate_duration
@commands = {}
@particles.each_with_index do |particle, i|
overall_commands = []
particle.each_pair do |property, value|
next if !value.is_a?(Array)
cmds = AnimationEditor::ParticleDataHelper.get_particle_property_commands_timeline(value, property)
@commands[[i, property]] = cmds
cmds.each_with_index do |cmd, j|
next if !cmd
overall_commands[j] = (cmd.is_a?(Array)) ? cmd.clone : cmd
end
end
@commands[i] = overall_commands
end
# Calculate visibilities for every keyframe
@particles.each_with_index do |particle, i|
@visibilities[i] = AnimationEditor::ParticleDataHelper.get_timeline_particle_visibilities(
particle, @duration - DURATION_BUFFER
)
end
end
# TODO: Methods that will show/hide individual property rows for a given
# @particles index.
def each_visible_keyframe(early_start = false)
full_width = @commands_viewport.rect.width
start_keyframe = ((@left_pos - TIMELINE_LEFT_BUFFER) / KEYFRAME_SPACING)
start_keyframe = 0 if start_keyframe < 0
start_keyframe -= 1 if early_start && start_keyframe > 0 # For drawing long timestamps
end_keyframe = (@left_pos + full_width / KEYFRAME_SPACING)
(start_keyframe..end_keyframe).each { |i| yield i }
end
def each_visible_particle
full_height = @list_viewport.rect.height
start_row = @top_pos / ROW_HEIGHT
end_row = (@top_pos + full_height) / ROW_HEIGHT
if @old_top_pos
old_start_row = @old_top_pos / ROW_HEIGHT
old_end_row = (@old_top_pos + full_height) / ROW_HEIGHT
(start_row..end_row).each { |i| yield i if !(old_start_row..old_end_row).include?(i) }
else
(start_row..end_row).each { |i| yield i }
end
end
#-----------------------------------------------------------------------------
def property_display_name(property)
return {
:graphic => "Graphic",
:frame => "Graphic frame",
:blending => "Blending",
:flip => "Flip",
:x => "X",
:y => "Y",
:zoom_x => "Zoom X",
:zoom_y => "Zoom Y",
:angle => "Angle",
:visible => "Visible",
:opacity => "Opacity"
}[property] || "Unnamed property"
end
def repaint
@list_scrollbar.repaint if @list_scrollbar.invalid?
@time_scrollbar.repaint if @time_scrollbar.invalid?
super if invalid?
end
def refresh_timeline
@timeline_sprite.bitmap.clear
# Draw hover highlight
hover_color = nil
if @captured_keyframe && !@captured_row
if @hover_keyframe && @hover_keyframe == @captured_keyframe && !@hover_row
hover_color = HOVER_COLOR
else
hover_color = CAPTURE_COLOR
end
draw_x = TIMELINE_LEFT_BUFFER + (@captured_keyframe * KEYFRAME_SPACING) - @left_pos
@timeline_sprite.bitmap.fill_rect(draw_x - (KEYFRAME_SPACING / 2), 0,
KEYFRAME_SPACING, TIMELINE_HEIGHT - 1, hover_color)
elsif !@captured_keyframe && !@captured_row && @hover_keyframe && !@hover_row
hover_color = HOVER_COLOR
draw_x = TIMELINE_LEFT_BUFFER + (@hover_keyframe * KEYFRAME_SPACING) - @left_pos
@timeline_sprite.bitmap.fill_rect(draw_x - (KEYFRAME_SPACING / 2), 0,
KEYFRAME_SPACING, TIMELINE_HEIGHT - 1, hover_color)
end
# Draw timeline markings
each_visible_keyframe(true) do |i|
draw_x = TIMELINE_LEFT_BUFFER + (i * KEYFRAME_SPACING) - @left_pos
line_height = 6
if (i % 20) == 0
line_height = TIMELINE_HEIGHT - 2
elsif (i % 5) == 0
line_height = TIMELINE_HEIGHT / 2
end
@timeline_sprite.bitmap.fill_rect(draw_x, TIMELINE_HEIGHT - line_height, 1, line_height, TEXT_COLOR)
draw_text(@timeline_sprite.bitmap, draw_x + 1, 0, (i / 20.0).to_s) if (i % 5) == 0
end
end
def refresh_position_line
@position_sprite.visible = (@keyframe && @keyframe >= 0)
if @keyframe >= 0
@position_sprite.x = TIMELINE_LEFT_BUFFER + (@keyframe * KEYFRAME_SPACING) - @left_pos
end
end
# TODO: Add indicator that this is selected (if so).
def refresh_particle_list_sprite(index)
spr = @list_sprites[index]
return if !spr
spr.bitmap.clear
# Get the background color
p_index = (@particle_list[index].is_a?(Array)) ? @particle_list[index][0] : @particle_list[index]
particle_data = @particles[p_index]
if particle_data[:name] == "SE"
bg_color = SE_CONTROL_BG
else
bg_color = CONTROL_BG_COLORS[@particles[@particle_list[index][0]][:focus]] || Color.magenta
end
# Draw hover highlight
hover_color = nil
if @captured_row && !@captured_keyframe
if @captured_row == index
if @hover_row && @hover_row == index && !@hover_keyframe
hover_color = HOVER_COLOR
else
hover_color = CAPTURE_COLOR
end
end
elsif !@captured_row && !@captured_keyframe && @hover_row && @hover_row == index && !@hover_keyframe
hover_color = HOVER_COLOR
end
spr.bitmap.fill_rect(0, 1, spr.width - 1, spr.height - 1, hover_color) if hover_color
# Draw outline
spr.bitmap.outline_rect(0, 1, spr.width - 1, spr.height - 1, bg_color, 2)
# Draw text
if @particle_list[index].is_a?(Array)
draw_text(spr.bitmap, 3 + 40, 3, property_display_name(@particle_list[index][1]))
else
draw_text(spr.bitmap, 3, 3, @particles[p_index][:name] || "Unnamed")
end
end
def refresh_particle_commands_bg_sprites(index)
bg_spr = @commands_bg_sprites[index]
return if !bg_spr
bg_spr.bitmap.clear
p_index = (@particle_list[index].is_a?(Array)) ? @particle_list[index][0] : @particle_list[index]
particle_data = @particles[p_index]
# Get the background color
if particle_data[:name] == "SE"
bg_color = SE_CONTROL_BG
else
bg_color = CONTROL_BG_COLORS[@particles[@particle_list[index][0]][:focus]] || Color.magenta
end
# Get visibilities of particle for each keyframe
visible_cmds = @visibilities[p_index]
# Draw background for visible parts of the particle
each_visible_keyframe do |i|
draw_x = TIMELINE_LEFT_BUFFER + (i * KEYFRAME_SPACING) - @left_pos
# Draw bg
if i < @duration - DURATION_BUFFER && (particle_data[:name] == "SE" || visible_cmds[i])
bg_spr.bitmap.fill_rect(draw_x, 1, KEYFRAME_SPACING, ROW_HEIGHT - 2, bg_color)
end
# Draw hover highlight
hover_color = nil
if @captured_row && @captured_keyframe
if @captured_row == index && @captured_keyframe == i
if @hover_row && @hover_row == index && @hover_keyframe && @hover_keyframe == i
hover_color = HOVER_COLOR
else
hover_color = CAPTURE_COLOR
end
end
elsif !@captured_row && !@captured_keyframe &&
@hover_row && @hover_row == index && @hover_keyframe && @hover_keyframe == i
hover_color = HOVER_COLOR
end
bg_spr.bitmap.fill_rect(draw_x - (KEYFRAME_SPACING / 2), 2, KEYFRAME_SPACING, ROW_HEIGHT - 3, hover_color) if hover_color
next if i >= @duration - DURATION_BUFFER
next if particle_data[:name] != "SE" && !visible_cmds[i]
# Draw outline
bg_spr.bitmap.fill_rect(draw_x, 1, KEYFRAME_SPACING, 1, Color.black) # Top
bg_spr.bitmap.fill_rect(draw_x, ROW_HEIGHT - 1, KEYFRAME_SPACING, 1, Color.black) # Bottom
if i <= 0 || (particle_data[:name] != "SE" && !visible_cmds[i - 1])
bg_spr.bitmap.fill_rect(draw_x, 1, 1, ROW_HEIGHT - 1, Color.black) # Left
end
if i == @duration - DURATION_BUFFER - 1 || (particle_data[:name] != "SE" && i < @duration - 1 && !visible_cmds[i + 1])
bg_spr.bitmap.fill_rect(draw_x + KEYFRAME_SPACING, 1, 1, ROW_HEIGHT - 1, Color.black) # Right
end
end
end
def refresh_particle_commands_sprite(index)
spr = @commands_sprites[index]
return if !spr
spr.bitmap.clear
cmds = @commands[@particle_list[index]]
return if !cmds
# Draw command diamonds
first_keyframe = -1
each_visible_keyframe do |i|
first_keyframe = i if first_keyframe < 0
next if !cmds[i]
draw_x = TIMELINE_LEFT_BUFFER + (i * KEYFRAME_SPACING) - @left_pos
# Draw command diamond
spr.bitmap.fill_diamond(draw_x, TIMELINE_HEIGHT / 2, DIAMOND_SIZE, TEXT_COLOR)
# Draw interpolation line
if cmds[i].is_a?(Array)
spr.bitmap.draw_interpolation_line(
draw_x + DIAMOND_SIZE + 2,
INTERP_LINE_Y,
cmds[i][0].abs * KEYFRAME_SPACING - ((DIAMOND_SIZE * 2) + 3),
INTERP_LINE_HEIGHT,
cmds[i][0] > 0, # Increases or decreases
cmds[i][1], # Interpolation type
TEXT_COLOR
)
end
end
# Draw any interpolation lines that start before the first visible keyframe
if first_keyframe > 0
(0...first_keyframe).each do |i|
next if !cmds[i] || !cmds[i].is_a?(Array)
next if i + cmds[i][0].abs < first_keyframe
draw_x = TIMELINE_LEFT_BUFFER + (i * KEYFRAME_SPACING) - @left_pos
spr.bitmap.draw_interpolation_line(
draw_x + DIAMOND_SIZE + 2,
INTERP_LINE_Y,
cmds[i][0].abs * KEYFRAME_SPACING - ((DIAMOND_SIZE * 2) + 3),
INTERP_LINE_HEIGHT,
cmds[i][0] > 0, # Increases or decreases
cmds[i][1], # Interpolation type
TEXT_COLOR
)
end
end
end
def refresh
draw_area_highlight
refresh_timeline if @invalid || @invalid_time
each_visible_particle do |i|
refresh_particle_list_sprite(i) if @invalid || @invalid_rows
refresh_particle_commands_bg_sprites(i)
refresh_particle_commands_sprite(i)
end
@old_top_pos = nil # For refreshing only rows that became visible via using vertical scrollbar
end
# Does nothing, because area highlights are drawn in other sprites rather than
# this one.
def draw_area_highlight; end
#-----------------------------------------------------------------------------
def get_interactive_element_at_mouse
ret = nil
mouse_x, mouse_y = mouse_pos
return ret if !mouse_x || !mouse_y
@interactions.each_pair do |area, rect|
next if !rect.contains?(mouse_x, mouse_y)
ret = area
case area
when :list
new_hover_row = (mouse_y + @top_pos - rect.y) / ROW_HEIGHT
break if new_hover_row >= @particle_list.length
ret = [area, nil, new_hover_row]
when :timeline
new_hover_keyframe = (mouse_x + @left_pos - rect.x - TIMELINE_LEFT_BUFFER + (KEYFRAME_SPACING / 2)) / KEYFRAME_SPACING
break if new_hover_keyframe < 0 || new_hover_keyframe >= @duration
ret = [area, new_hover_keyframe, nil]
when :commands
new_hover_row = (mouse_y + @top_pos - rect.y) / ROW_HEIGHT
new_hover_keyframe = (mouse_x + @left_pos - rect.x - TIMELINE_LEFT_BUFFER + (KEYFRAME_SPACING / 2)) / KEYFRAME_SPACING
break if new_hover_row >= @particle_list.length
break if new_hover_keyframe < 0 || new_hover_keyframe >= @duration
ret = [area, new_hover_keyframe, new_hover_row]
end
break
end
return ret
end
def on_mouse_press
return if @captured_area
hover_element = get_interactive_element_at_mouse
if hover_element.is_a?(Array)
@captured_area = hover_element[0]
@captured_keyframe = hover_element[1]
@captured_row = hover_element[2]
end
end
def on_mouse_release
return if !@captured_area # Wasn't captured to begin with
# Change this control's value
hover_element = get_interactive_element_at_mouse
if hover_element.is_a?(Array)
if @captured_area == hover_element[0] &&
@captured_keyframe == hover_element[1] &&
@captured_row == hover_element[2]
set_changed if @keyframe != @captured_keyframe || @particle_index != @captured_row
@keyframe = @captured_keyframe || -1
@particle_index = @captured_row || -1
end
end
@captured_keyframe = nil
@captured_row = nil
super # Make this control not busy again
end
def update_hover_highlight
# Remove the hover highlight if there are no interactions for this control
# or if the mouse is off-screen
mouse_x, mouse_y = mouse_pos
if !@interactions || @interactions.empty? || !mouse_x || !mouse_y
invalidate if @hover_area
@hover_area = nil
@hover_keyframe = nil
@hover_row = nil
return
end
# Check each interactive area for whether the mouse is hovering over it, and
# set @hover_area accordingly
hover_element = get_interactive_element_at_mouse
if hover_element.is_a?(Array)
invalidate if @hover_area != hover_element[0] # Moved to a different region
case hover_element[0]
when :list
invalidate_rows if @hover_row != hover_element[2]
when :timeline
invalidate_time if @hover_keyframe != hover_element[1]
when :commands
invalidate_commands if @hover_row != hover_element[2] ||
@hover_keyframe != hover_element[1]
end
@hover_area = hover_element[0]
@hover_keyframe = hover_element[1]
@hover_row = hover_element[2]
elsif hover_element
if @hover_area == hover_element
case @hover_area
when :list
invalidate_rows if @hover_row
when :timeline
invalidate_time if @hover_keyframe
when :commands
invalidate_commands if @hover_keyframe || @hover_row
end
else # Moved to a different region
invalidate
end
@hover_area = hover_element
@hover_keyframe = nil
@hover_row = nil
else
invalidate if @hover_area
@hover_area = nil
@hover_keyframe = nil
@hover_row = nil
end
end
def update
return if !self.visible
@list_scrollbar.update
@time_scrollbar.update
super
# Refresh sprites if a scrollbar has been moved
self.left_pos = @time_scrollbar.position
self.top_pos = @list_scrollbar.position
# Update the current keyframe line's position
refresh_position_line
# TODO: This is testing code, and should be replaced by clicking on the
# timeline or a command sprite. Maybe keep it after all?
if Input.trigger?(Input::LEFT)
if @keyframe > 0
@keyframe -= 1
echoln "keyframe = #{@keyframe}"
set_changed
end
elsif Input.trigger?(Input::RIGHT)
if @keyframe < @duration - DURATION_BUFFER
@keyframe += 1
echoln "keyframe = #{@keyframe}"
set_changed
end
elsif Input.trigger?(Input::UP)
if @particle_index > 0
@particle_index -= 1
echoln "particle_index = #{@particle_index}"
set_changed
end
elsif Input.trigger?(Input::DOWN)
if @particle_index < @particles.length - 1
@particle_index += 1
echoln "particle_index = #{@particle_index}"
set_changed
end
end
end
end