% % Date: Tue, 27 Jun 89 12:29:26 EDT % From: alexis%yummy@gateway.mitre.org % To: NeWS-makers@brillig.umd.edu % Subject: Another rework of the psPyro % % Yet another remake/tweek of the psPyro program, making it more % worthy of a workstation (read as "it sucks us cpu cycles"). This % version has lots of colors, more interesting explosions, more than % one firecracker in the air at once (I have it set to 3, but it's % just a variable), and general tweeking (they fly faster, explode % slower, etc). This just assumes you're running on a color machine. % % alexis wieland % alexis%yummy@gateway.mitre.org % % --------------------------- cut here ---------------------- % % psPyro, a user extensible fireworks display screen saver. % % % Physical screen dimensions ------------------------------------------ % /screen_width 0 def /screen_height 0 def % % Heuristics for firework creation and display (user configurable) ---- % /unusable_screen_width 0.1 def % set to percent of physical screen width /unusable_screen_height 0.1 def % set to percent of physical screen height /minimum_trail_height 0.75 def % set to percent of physical screen height /minimum_explosion_angle 100 def /maximum_explosion_angle 150 def /minimum_#_explosions 2 def /maximum_#_explosions 6 def /trail_length 5 def % the length of the firework trail /n-in-air-at-once 3 def % number of fireworks at any time /multiple_explosion_radius 100 def % radius of multiple explosions from original % array of colors /colortable [ 1 1 1 rgbcolor 1 0 0 rgbcolor 0 1 0 rgbcolor 0 0 1 rgbcolor 1 1 0 rgbcolor 0 1 1 rgbcolor 1 .5 0 rgbcolor 1 0 .5 rgbcolor .8 .5 .2 rgbcolor .92 .68 .92 rgbcolor .86 .44 .86 rgbcolor ] def % randomly set color /randcolor { colortable random colortable length 1 sub mul floor cvi get setcolor } def % % Firework explosion definitions % % array to keep the names of the different explosions in /explosion_kinds [ /dots_explosion /circle_explosion /star_explosion /colored_circle_explosion ] def % % Dots explosion. /draw_one_quarter { 30 0 moveto 2 -2 rlineto 2 2 rlineto -2 2 rlineto closepath fill 20 10 3 3 rectpath fill 10 20 3 3 rectpath fill } def /dots_explosion { % x y => - gsave translate 360 random mul rotate 8 random mul cvi 2 add .5 random add dup scale gsave 5 { randcolor dup { draw_one_quarter 360 1 index div rotate } repeat 1.3 1.3 scale big_delay } repeat grestore gsave 5 { 0 setgray dup { draw_one_quarter 360 1 index div rotate } repeat 1.3 1.3 scale big_delay } repeat pop grestore grestore } def % dots_explosion % % Circle explosion. % /draw_circle { % - => - 0 0 10 0 360 arc stroke } def /circle_explosion { % x y => - gsave translate .5 random add dup scale gsave 6 { 1.4 dup scale randcolor big_delay draw_circle } repeat grestore gsave 6 { 1.4 dup scale 0 setgray big_delay draw_circle } repeat grestore grestore } def % % Star explosion. % /draw_star { % n-lines => n-lines gsave cvi dup { -30 0 moveto 60 0 rlineto stroke 360 1 index div rotate } repeat grestore } def /star_explosion { % x y => - gsave translate .5 random add dup scale 360 random mul rotate 10 random mul 4 add gsave 4 { 1.4 dup scale randcolor big_delay draw_star } repeat grestore gsave 4 { 1.4 dup scale 0 setgray big_delay draw_star } repeat grestore pop grestore } def % % Colored circle explosion. % /draw_dot { % - => - 0 0 10 0 360 arc fill } def /colored_circle_explosion { % x y => - gsave translate .5 random add dup scale gsave 10 { 1.2 dup scale randcolor big_delay draw_dot } repeat 0 setgray big_delay big_delay draw_dot grestore grestore } def % % Support utilities --------------------------------------------------- % % % Delay loops. % /big_delay { 1 2048 div sleep } def % % Draw one instance of a firework trail from: % angle to angle % theta theta + trail_length - 1 % /draw_trail { % theta => - /theta exch def % erase the first degree from the previous trail 0 setgray 0 0 1 theta 1 sub theta newpath arc stroke 1 setgray theta 1 theta trail_length add 1 sub { 0 0 1 4 -1 roll dup 1 add newpath arc stroke } for } def % % Animate the entire firework trail up until the explosion. % /animate_trail { % - => - % draw the first trail instance 1 setgray 0 1 trail_length 1 sub { 0 0 1 4 -1 roll dup 1 add newpath arc stroke } for % draw the rest of the trail 1 1 explosion_angle { draw_trail pause } for % remove the last trail instance 0 setgray explosion_angle 1 explosion_angle trail_length add 1 sub { 0 0 1 4 -1 roll dup 1 add newpath arc stroke } for } def % % Determine the characterictics of the next firework. % /determine_firework_characteristics { % - => - % randomly pick the starting position to fire the firework from /trail_start_x screen_width random mul store % % pick the direction of the firework trail % % if the picked starting position is too close to a screen % edge, force the direction to be towards the opposite screen % side, otherwise randomly pick the direction % trail_start_x unusable_screen_width le { /trail_going_left? false store } { trail_start_x screen_width unusable_screen_width sub ge { /trail_going_left? true store } { % randomly pick the direction /trail_going_left? random round 0 eq store } ifelse } ifelse % randomly pick the width of the firework trail trail_going_left? { /trail_width trail_start_x random mul store } { /trail_width screen_width trail_start_x sub random mul store } ifelse % randomly pick the height of the firework trail /trail_height screen_height random mul store trail_height minimum_trail_height le { /trail_height minimum_trail_height store } if % randomly pick the ending angle of the firework explosion /explosion_angle maximum_explosion_angle minimum_explosion_angle sub random mul minimum_explosion_angle add round store } def % % Animate a firework explosion. % /animate_explosion { % explosion_x explosion_y #explosions => - /#explosions exch cvi store /explosion_y exch store /explosion_x exch store % randomly pick which explosion to use /which_explosion explosion_kinds explosion_kinds length random mul floor cvi get def % explode the first of the explosions explosion_x explosion_y which_explosion cvx exec % explode the remaining number of explosions (possible none), % randomly picking each location based upon the initial explosion % location #explosions 1 sub { % randomly pick another explosion location 360 random mul dup cos multiple_explosion_radius mul explosion_x add exch sin multiple_explosion_radius mul explosion_y add which_explosion cvx exec } repeat } def /do-it { gsave /trail_width 0 def /trail_height 0 def /trail_start_x 0 def /trail_going_left? true def /explosion_angle 0 def /#explosions null store /explosion_y null store /explosion_x null store /which_explosion null store initmatrix sky setcanvas % create a new firework determine_firework_characteristics % translate to the center of the firework trail arc trail_start_x unusable_screen_width add trail_width 2 div trail_going_left? { sub } { add } ifelse 0 translate trail_going_left? not { -1 1 scale } if % create the firing of the firework randcolor trail_width 2 div 0 20 0 180 arc fill 3 { big_delay } repeat 0 setgray trail_width 2 div 0 20 0 180 arc fill % create the firework trail trail_width 2 div trail_height scale animate_trail % calculate the location of the firework explosion initmatrix trail_start_x unusable_screen_width add trail_width 2 div trail_going_left? { sub } { add } ifelse explosion_angle trail_length add cos trail_width 2 div mul trail_going_left? { add } { sub } ifelse explosion_angle trail_length add sin trail_height mul % calculate the number of explosions for the firework maximum_#_explosions random mul round minimum_#_explosions max % create the explosion! animate_explosion grestore } def % % Continually make fireworks. % /make_fireworks { % - => - { n-in-air-at-once { { 32 dict begin { do-it } loop end } fork } repeat } fork } def % % Main ---------------------------------------------------------- % % get the dimensions of the physical screen clippath pathbbox /screen_height exch def /screen_width exch def clear % calculate the actual values of the firework creation and display heuristics /unusable_screen_width screen_width unusable_screen_width mul def /unusable_screen_height screen_height unusable_screen_height mul def /minimum_trail_height screen_height minimum_trail_height mul def % calculate the usable screen area /screen_height screen_height unusable_screen_height sub def /screen_width screen_width unusable_screen_width dup add sub def % create the black sky clippath pathbbox rectpath /sky framebuffer newcanvas def sky reshapecanvas sky /Mapped true put sky setcanvas 0 fillcanvas % remove the cursor /nouse /nouse_m sky setstandardcursor % start the fireworks display make_fireworks % wait for a mouse movement or click to end the fireworks display createevent dup begin /Name [ /LeftMouseButton /MiddleMouseButton /RightMouseButton /MouseDragged ] def /Canvas sky def end expressinterest awaitevent currentprocess killprocessgroup