c /////////////////////////////////////////////////////////////////
c
c maximum number of planes we might have to deal with:
      parameter (max_planes=8)
c
c in general, dem1, dem2 are FEC-type chips, demm is a marebo, and demd
c is a module.
c
      common /event_display/ window_is_open, 
     .	ix11window1_id, ix11window1_x0, ix11window1_y0,
     .	ix11window1_width, ix11window1_height,
     .	ix11window1_width_default, ix11window1_height_default,
     .	pixels_per_x,
     .	pixels_per_y, pixels_per_zx, pixels_per_zy,
     .	pixels_per_x_default,
     .	pixels_per_y_default, pixels_per_zx_default, 
     .	pixels_per_zy_default,
     .	factor_dem_z_exaggerate,
     .	number_strips, number_rows_dem1, 
     .	number_rows_dem2, number_rows_demm, number_rows_demd,
     .	number_cols_dem1, 
     .	number_cols_per_modchip, number_rows_per_modchip,
     .	number_shared_rows, number_chips_per_mod,
     .	number_cols_dem2, number_cols_demm, number_cols_demd,
     .	number_fatcols_dem1, number_fatcols_dem2,
     .	number_fatcols_demm, number_fatcols_demd,
     .  pixel_at_x_0, pixel_at_y_0, pixel_at_zx_0, pixel_at_zy_0,
     .  pixel_at_x_0_default, pixel_at_y_0_default, 
     .	pixel_at_zx_0_default, pixel_at_zy_0_default,
     .  pixel_at_x_9, pixel_at_y_9, pixel_at_zx_9, pixel_at_zy_9,
     .  pixel_at_x_9_default, pixel_at_y_9_default, 
     .	pixel_at_zx_9_default, pixel_at_zy_9_default,
     .	xplane_x0(max_planes), xplane_z0(max_planes), 
     .	yplane_y0(max_planes), yplane_z0(max_planes),
     .	xplane_x0_default(max_planes), xplane_z0_default(max_planes), 
     .	yplane_y0_default(max_planes), yplane_z0_default(max_planes),
     .	strip_pitch, dem1_pitch_fine, dem1_pitch_coarse,
     .	dem2_pitch_fine, dem2_pitch_coarse, 
     .	demm_pitch_fine, demm_pitch_coarse, 
     .	demd_pitch_fine, demd_pitch_coarse, demd_pitch_coarse2,
     .	ipldem1, ipldem2, ipldemm, ipldemd,
     .	icol_polarity_dem1, irow_polarity_dem1, iswap_rows_cols_dem1, 
     .	icol_polarity_dem2, irow_polarity_dem2, iswap_rows_cols_dem2, 
     .	icol_polarity_demm, irow_polarity_demm, iswap_rows_cols_demm, 
     .	icol_polarity_demd, irow_polarity_demd, iswap_rows_cols_demd, 
     .  phidem1, psidem1, thetadem1, phidem2, psidem2, thetadem2,
     .  phidemm, psidemm, thetademm,
     .  phidemd, psidemd, thetademd,
     .	pixels_clearance, shift_right, top_edge_x, bot_edge_x,  
     .	top_edge_y, bot_edge_y, left_edge_z, right_edge_z,
     .	message_left, message_right, message_top, message_bot,
     .	message_height,
     .	max_strip_pulseheight, max_dem1_pulseheight,
     .	max_dem2_pulseheight,  max_demm_pulseheight,
     .	max_demd_pulseheight,
     .	pixels_per_strip_pulseheightx, 
     .	pixels_per_dem1_pulseheightx, pixels_per_dem2_pulseheightx,
     .	pixels_per_demm_pulseheightx,  pixels_per_demd_pulseheightx,
     .	pixels_per_strip_pulseheighty, 
     .	pixels_per_dem1_pulseheighty, pixels_per_dem2_pulseheighty,
     .	pixels_per_demm_pulseheighty, pixels_per_demd_pulseheighty,
     .	itext_pixels, button_row_height, number_of_buttons,
     .	button_left(20), button_right(20), button_top(20), 
     .	button_bot(20), map_button(20), map_button_inverse(20),
     .	next_event_button, 
     .	new_dem1_phi_button,new_dem1_psi_button,new_dem1_theta_button,
     .	new_dem2_phi_button,new_dem2_psi_button,new_dem2_theta_button,
     .	new_demm_phi_button,new_demm_psi_button,new_demm_theta_button,
     .	new_demd_phi_button,new_demd_psi_button,new_demd_theta_button,
     .	istop_button, i_want_to_stop, izoom_button,
     .	delta_angle_per_click,iprevious_mouse_button,iprevious_button,
     .	icurrent_mouse_button,icurrent_button,
     .	icurrent_click_pixel_x, icurrent_click_pixel_y,
     .	iprevious_click_pixel_x, iprevious_click_pixel_y,
     .	icurrent_sample_pixel_x, icurrent_sample_pixel_y,
     .	iprevious_sample_pixel_x, iprevious_sample_pixel_y,
     .	lun_data, lun_parameters, lun_default_parameters, lun_control,
     .	number_for_control_file, i_want_new_event,
     .	index_color_white, index_color_black, index_color_red,
     .	index_color_green, index_color_blue, index_color1, index_color2,
     .	index_color3, index_color_button, index_color_message,
     .	index_color_xview, index_color_yview,
     .	iamzooming_x, iamzooming_y, x_has_been_zoomed,
     .	y_has_been_zoomed, iamzooming, icurrent_click_in_x_window,
     .	icurrent_click_in_y_window, iprevious_click_in_x_window,
     .	iprevious_click_in_y_window, 
     .	irubber_cursor, idefault_cursor, 
     .	telescope_max_zx,
     .	telescope_max_zy, telescope_max_x, telescope_max_y,
     .	telescope_max_zx_default, telescope_max_zy_default, 
     .	telescope_max_x_default, telescope_max_y_default,
     .	telescope_min_zx,
     .	telescope_min_zy, telescope_min_x, telescope_min_y,
     .	telescope_min_zx_default, telescope_min_zy_default, 
     .	telescope_min_x_default, telescope_min_y_default,
     .	something_changed

c
	real left_edge_z
c
	logical window_is_open, i_want_to_stop, i_want_new_event
	logical iamzooming_x, iamzooming_y, iamzooming 
   	logical x_has_been_zoomed, y_has_been_zoomed
	logical icurrent_click_in_x_window, icurrent_click_in_y_window
	logical iprevious_click_in_x_window
	logical iprevious_click_in_y_window
	logical something_changed
c
c window_is_open is true if a graphics window has already been opened.
c
c ix11window1_id is a window ID for the main graphics window.
c
c ix11window1_x0, ix11window1_y are the initial x,y positions for X11 window 1
c in pixels: note that X coordinates have increasing x moving to the right on 
c the screen, increasing y moving down. origin is upper left corner of screen.
c
c ix11window1_width, ix11window1_height are width and height, in pixels, for 
c X11 window 1
c
c ix11window1_title is the title for window 1.
c
c pixels_per_xy, pixels_per_z are pixels per millimeter in x (or y) and z
c for the telescope's h8 lab frame. pixels_per_x, pixels_per_y are for5
c use in situations when i want separate scales in the two views.
c ditto pixels_per_zx, pixels_per_zy.
c
c pixel_at_x_0, ...y_0, ...z_0 are the screen coordinates describing
c where telescope coordinates x=0, z=0 and y=0, z=0 are to be plotted in
c the display window. 
c
c xplane_x0(7), xplane_z0(7) are telescope frame coordinates for the
c four strip planes (1-4), dem1 plane (5), dem2 plane (6), and marebo (7). 
c Use these
c to say where the "raw" detector coordinate (eg, the first strip at x=0)
c lives in the lab frame relative to a perfectly aligned detector (units are 
c millimeters). I can use this at some point to work up alignments.
c
c yplane_y0(7), yplane_z0(7) work similarly.
c
c strip_pitch is the width of one strip, in millimeters.
c
c dem1_pitch_fine, dem1_pitch_coarse are fine and coarse pixel widths for
c demonstrator 1. dem2_pitch_fine, dem2_pitch_coarse are for the other chip.
c
c ipldem1, ipldem2 are 5,6 to indicate which planes the pixel detectors are.
c ipldemm is 7 for marebo.
c
c phidem1, psidem1, thetadem1 describe rotation angles (degrees) to describe 
c dem1's location in space. similar definitions for dem2...
c
c pixels_clearance is the number of pixels of white space I want to use in
c various places...
c
c shift_right is an extra distance to shift stuff to the right so that I
c gave space for some labels to the left of the first plane if desired.
c
c top_edge_x, bot_edge_x, top_edge_y, bot_edge_y are pixel vertical 
c coordinates for the upper and lower edges of the two telescope view plots.
c
c left_edge_z, right_edge_z are the pixel horizontal coordinates for the
c two telescope views.
c
c message_left, message_right, message_top, message_bot are pixels for the
c edges of the area meant to hold status messages.
c
c max_strip_pulseheight, max_dem1_pulseheight, max_dem2_pulseheight are
c only used to give me an idea how large the signals migh be so I can 
c calculate the scaling required to keep the tickmarks from bumping into
c the next plane.
c
c pixels_per_strip_pulseheight, pixels_per_dem1_pulseheight, and
c pixels_per_dem2_pulseheight give the number of pixels per unit ADC count.
c
c itext_pixels is the approximate height, in pixels, of text I'll write.
c
c button_row_height is the number of pixels high I'll use to make a set
c of buttons
c
c message_height is the height of the nmessage window.
c
c number_of_buttons is the number of buttons to put in this row.
c
c button_left(20), button_right(20), button_top(20), button_bot(20) are
c pixel coordinates for the edges of up to 20 buttons.
c
c map_button(j) tells which button on the screen the particular button in 
c question actually maps to.
c
c next_event_button says which screen button refers to request for next event
c
c new_dem1_phi_button, new_dem1_psi_button , new_dem1_theta_button say which 
c buttons are for requests to enter new phi, psi, theta values for dem1. 
c similarly for dem2...
c
c delta_angle_per_click is the number of degrees per mouse button click to
c change the phi, psi, theta angles.
c
c istop_button indicates which button to click to stop the program.
c
c icurrent_mouse_button, icurrent_button are numbers of most recently
c detected mouse button that was clicked (1=left, 2=middle, 3=right) and
c window button that was clicked.
c
c icurrent_click_pixel_x, icurrent_click_pixel_y are the x,y values for the
c display window pixel of the most recent mouse click.
c
c iprevious_mouse_button,iprevious_button are similar, but for next-most-
c recently detected button clicks.
c
c iprevious_click_pixel_x, iprevious_click_pixel_y are the x,y values for the
c display window pixel of the previous mouse click.
c
c icol_polarity_dem1, irow_polarity_dem1, iswap_rows_cols_dem1 deal with
c how I label the rows and columns. ditto for dem2...
c
c factor_dem_z_exaggerate is a scale factor to exaggerate how much I show
c the change in z position of the corners of the pixel planes in order to 
c make it easier to see the rotations.
c
c lun_data is unit for event data.
c
c lun_control is unit for event data.
c
c lun_parameters is unit for a file holding various pieces of configuration
c information, stuff like z positions.
c
c lun_default_parameters is the unit for a file I'll have the program write
c which can serve as a template for the parameter file.
c
c file_data is the file name for event data
c
c file_default_parameters is the file name for the default parameters I'll 
c write
c
c i_want_to_stop is set .true. by the mouse event routine when it's time to
c stop, since the user clicked the stop button.
c
c number_for_control_file is the number written to the control file: it is
c the periodicity with which to write events to the buffeering file. make
c it 1 to get the next available event, larger to skip a bunch of events.
c
c i_want_new_event is .true. if the user has asked for a new event.
c
c index_color_white, index_color_black, index_color_red, index_color_green, 
c and index_color_blue are color indices to use with the X11 routines.
c index_color1, etc. refer to home-brewed colors I might want to use.
c
c iamzooming_x, iamzooming_y, iamzooming x_has_been_zoomed, y_has_been_zoomed
c give status information about computing/executing zooms.
c
c icurrent_click_in_x_window, icurrent_click_in_y_window are set when the last
c mouse click was in the x-view window or y-view window.
c
c irubber_cursor, idefault_cursor are cursor numbers for two kinds
c of cursors.
c
c telescope_max_zx, telescope_max_zy, telescope_max_x, telescope_max_y are
c telescope coordinates which map into the last pixels in the plot area.
c
c something_changed is true when the detector geometry, or X window size
c has changed sine the last time event_display_initialize_geometry was called.
c 
c
c fortran tends to complain if character variables live in the same common
c block as non-character variables, so segregate them:
      common /event_display_char/ hostname, ix11window1_title,
     .	button_labels(20),
     .	file_data, file_default_parameters, file_control,
     .	file_data_cern, file_default_parameters_cern, 
     .	file_control_cern,
     .	file_data_cppm, file_default_parameters_cppm, 
     .	file_control_cppm,
     .	font_name(10),
     .	web_document_url, web_document_url_IP,
     .  web_document_url_path
c
      character*120 hostname, ix11window1_title, button_labels
      character*120 file_data, file_default_parameters, file_control
      character*120
     .	file_data_cern, file_default_parameters_cern, 
     .	file_control_cern,
     .	file_data_cppm, file_default_parameters_cppm, 
     .	file_control_cppm
      character*200 web_document_url
      character*100 web_document_url_IP, web_document_url_path
      character*80 font_name
c
c
c hostname is name of device on which the graphics will be drawn.
c
c ix11window1_title is the X11 window1's title. 
c
c button_labels are labels to put in the button boxes.
c
c file_data is the file name for event data
c
c file_default_parameters is the file name for the default parameters I'll 
c write to disk; can be used as a template for other parameter files.
c
c file_control is the name of a file I'll use to communicate with the
c routine that launches display program this in standalone mode.
c
c ... _cern are the file names to be used when running at cern
c ... _cppm are the file names to be used when I am running this at cppm
c
c font_name is an array holding a list of X11 font names I'd like 
c to try using.
c
c web_document_url is the URL of a web page describing the event display.
c I build it up from  web_document_url_IP, web_document_url_path since
c URL names can be so long!
c
c \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\