#!/usr/bin/gmake -f
LDFLAGS=-lm
CFLAGS=-Wall
SELF=$(word $(words $(MAKEFILE_LIST)),$(MAKEFILE_LIST))
REGEX_QUOTE=$(subst .,\.,$(subst /,\/,$(subst \,\\,$(1))))

.PHONY: all
all: gtf

.INTERMEDIATE: %.c
%.c:
	sed -n '/^#> $(call REGEX_QUOTE,$@)$$/,/^$$/{ ; s/^#= // ; T ; p ; }' < $(SELF) > $@

#> gtf.c
#= /* gtf.c  Generate mode timings using the GTF Timing Standard
#=  *
#=  * Copyright (c) 2001, Andy Ritger  aritger@nvidia.com
#=  * All rights reserved.
#=  * 
#=  * Redistribution and use in source and binary forms, with or without
#=  * modification, are permitted provided that the following conditions
#=  * are met:
#=  * 
#=  * o Redistributions of source code must retain the above copyright
#=  *   notice, this list of conditions and the following disclaimer.
#=  * o Redistributions in binary form must reproduce the above copyright
#=  *   notice, this list of conditions and the following disclaimer
#=  *   in the documentation and/or other materials provided with the
#=  *   distribution.
#=  * o Neither the name of NVIDIA nor the names of its contributors
#=  *   may be used to endorse or promote products derived from this
#=  *   software without specific prior written permission.
#=  *
#=  *
#=  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
#=  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT
#=  * NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
#=  * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
#=  * THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
#=  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
#=  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
#=  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
#=  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
#=  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
#=  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
#=  * POSSIBILITY OF SUCH DAMAGE.
#=  *
#=  * 
#=  *
#=  * This program is based on the Generalized Timing Formula(GTF TM)
#=  * Standard Version: 1.0, Revision: 1.0
#=  *
#=  * The GTF Document contains the following Copyright information:
#=  *
#=  * Copyright (c) 1994, 1995, 1996 - Video Electronics Standards
#=  * Association. Duplication of this document within VESA member
#=  * companies for review purposes is permitted. All other rights
#=  * reserved.
#=  *
#=  * While every precaution has been taken in the preparation
#=  * of this standard, the Video Electronics Standards Association and
#=  * its contributors assume no responsibility for errors or omissions,
#=  * and make no warranties, expressed or implied, of functionality
#=  * of suitability for any purpose. The sample code contained within
#=  * this standard may be used without restriction.
#=  *
#=  * 
#=  *
#=  * The GTF EXCEL(TM) SPREADSHEET, a sample (and the definitive)
#=  * implementation of the GTF Timing Standard, is available at:
#=  *
#=  * ftp://ftp.vesa.org/pub/GTF/GTF_V1R1.xls
#=  *
#=  *
#=  *
#=  * This program takes a desired resolution and vertical refresh rate,
#=  * and computes mode timings according to the GTF Timing Standard.
#=  * These mode timings can then be formatted as an XFree86 modeline
#=  * or a mode description for use by fbset(8).
#=  *
#=  *
#=  *
#=  * NOTES:
#=  *
#=  * The GTF allows for computation of "margins" (the visible border
#=  * surrounding the addressable video); on most non-overscan type
#=  * systems, the margin period is zero.  I've implemented the margin
#=  * computations but not enabled it because 1) I don't really have
#=  * any experience with this, and 2) neither XFree86 modelines nor
#=  * fbset fb.modes provide an obvious way for margin timings to be
#=  * included in their mode descriptions (needs more investigation).
#=  * 
#=  * The GTF provides for computation of interlaced mode timings;
#=  * I've implemented the computations but not enabled them, yet.
#=  * I should probably enable and test this at some point.
#=  *
#=  * 
#=  *
#=  * TODO:
#=  *
#=  * o Add support for interlaced modes.
#=  *
#=  * o Implement the other portions of the GTF: compute mode timings
#=  *   given either the desired pixel clock or the desired horizontal
#=  *   frequency.
#=  *
#=  * o It would be nice if this were more general purpose to do things
#=  *   outside the scope of the GTF: like generate double scan mode
#=  *   timings, for example.
#=  *   
#=  * o Printing digits to the right of the decimal point when the
#=  *   digits are 0 annoys me.
#=  *
#=  * o Error checking.
#=  *
#=  */
#= 
#= 
#= #include <stdio.h>
#= #include <stdlib.h>
#= #include <math.h>
#= 
#= 
#= 
#= #define MARGIN_PERCENT    1.8   /* % of active vertical image                */
#= #define CELL_GRAN         8.0   /* assumed character cell granularity        */
#= #define MIN_PORCH         1     /* minimum front porch                       */
#= #define V_SYNC_RQD        3     /* width of vsync in lines                   */
#= #define H_SYNC_PERCENT    8.0   /* width of hsync as % of total line         */
#= #define MIN_VSYNC_PLUS_BP 550.0 /* min time of vsync + back porch (microsec) */
#= #define M                 600.0 /* blanking formula gradient                 */
#= #define C                 40.0  /* blanking formula offset                   */
#= #define K                 128.0 /* blanking formula scaling factor           */
#= #define J                 20.0  /* blanking formula scaling factor           */
#= 
#= /* C' and M' are part of the Blanking Duty Cycle computation */
#= 
#= #define C_PRIME           (((C - J) * K/256.0) + J)
#= #define M_PRIME           (K/256.0 * M)
#= 
#= 
#= /* struct definitions */
#= 
#= typedef struct __mode
#= {
#= 	int hr, hss, hse, hfl;
#= 	int vr, vss, vse, vfl;
#= 	float pclk, h_freq, v_freq;
#= } mode;
#= 
#= 
#= typedef struct __options
#= {
#= 	int x, y;
#= 	int xf86mode, fbmode;
#= 	float v_freq;
#= } options;
#= 
#= 
#= 
#= 
#= /* prototypes */
#= 
#= void print_value(int n, char *name, float val);
#= void print_xf86_mode (mode *m);
#= void print_fb_mode (mode *m);
#= mode *vert_refresh (int h_pixels, int v_lines, float freq,
#= 					int interlaced, int margins);
#= options *parse_command_line (int argc, char *argv[]);
#= 
#= 
#= 
#= 
#= /*
#=  * print_value() - print the result of the named computation; this is
#=  * useful when comparing against the GTF EXCEL spreadsheet.
#=  */
#= 
#= int global_verbose = 0;
#= 
#= void print_value(int n, char *name, float val)
#= {
#= 	if (global_verbose) {
#= 		printf("%2d: %-27s: %15f\n", n, name, val);
#= 	}
#= } // print_value()
#= 
#= 
#= 
#= /* print_xf86_mode() - print the XFree86 modeline, given mode timings. */
#= 
#= void print_xf86_mode (mode *m)
#= {
#= 	printf ("\n");
#= 	printf ("  # %dx%d @ %.2f Hz (GTF) hsync: %.2f kHz; pclk: %.2f MHz\n",
#= 			m->hr, m->vr, m->v_freq, m->h_freq, m->pclk);
#= 	
#= 	printf ("  Modeline \"%dx%d_%.2f\"  %.2f"
#= 			"  %d %d %d %d"
#= 			"  %d %d %d %d"
#= 			"  -HSync +Vsync\n\n",
#= 			m->hr, m->vr, m->v_freq, m->pclk,
#= 			m->hr, m->hss, m->hse, m->hfl,
#= 			m->vr, m->vss, m->vse, m->vfl);
#= 	
#= } // print_xf86_mode()
#= 
#= 
#= 
#= /*
#=  * print_fb_mode() - print a mode description in fbset(8) format;
#=  * see the fb.modes(8) manpage.  The timing description used in
#=  * this is rather odd; they use "left and right margin" to refer
#=  * to the portion of the hblank before and after the sync pulse
#=  * by conceptually wrapping the portion of the blank after the pulse
#=  * to infront of the visible region; ie:
#=  * 
#=  *
#=  * Timing description I'm accustomed to:
#=  *
#=  *
#=  *
#=  *     <--------1--------> <--2--> <--3--> <--4-->
#=  *                                _________
#=  *    |-------------------|_______|       |_______
#=  *
#=  *                        R       SS      SE     FL
#=  *       
#=  * 1: visible image
#=  * 2: blank before sync (aka front porch)
#=  * 3: sync pulse
#=  * 4: blank after sync (aka back porch)
#=  * R: Resolution
#=  * SS: Sync Start
#=  * SE: Sync End
#=  * FL: Frame Length
#=  *
#=  *
#=  * But the fb.modes format is:
#=  *
#=  *
#=  *    <--4--> <--------1--------> <--2--> <--3--> 
#=  *                                       _________
#=  *    _______|-------------------|_______|       |
#=  *  
#=  * The fb.modes(8) manpage refers to <4> and <2> as the left and
#=  * right "margin" (as well as upper and lower margin in the vertical
#=  * direction) -- note that this has nothing to do with the term
#=  * "margin" used in the GTF Timing Standard.
#=  *
#=  * XXX always prints the 32 bit mode -- should I provide a command
#=  * line option to specify the bpp?  It's simple enough for a user
#=  * to edit the mode description after it's generated.
#=  */
#= 
#= void print_fb_mode (mode *m)
#= {
#= 	printf ("\n");
#= 	printf ("mode \"%dx%d %.2fHz 32bit (GTF)\"\n",
#= 			m->hr, m->vr, m->v_freq);
#= 	printf ("    # PCLK: %.2f MHz, H: %.2f kHz, V: %.2f Hz\n",
#= 			m->pclk, m->h_freq, m->v_freq);
#= 	printf ("    geometry %d %d %d %d 32\n",
#= 			m->hr, m->vr, m->hr, m->vr);
#= 	printf ("    timings %d %d %d %d %d %d %d\n",
#= 			(int) rint(1000000.0/m->pclk),// pixclock in picoseconds
#= 			m->hfl - m->hse,              // left margin (in pixels)
#= 			m->hss - m->hr,               // right margin (in pixels)
#= 			m->vfl - m->vse,              // upper margin (in pixel lines)
#= 			m->vss - m->vr,               // lower margin (in pixel lines)
#= 			m->hse - m->hss,              // horizontal sync length (in pixels)
#= 			m->vse - m->vss);             // vert sync length (in pixel lines)
#= 	printf ("    hsync low\n");
#= 	printf ("    vsync high\n");
#= 	printf ("endmode\n\n");
#= 	
#= } // print_fb_mode()
#= 
#= 
#= 
#= 
#= /*
#=  * vert_refresh() - as defined by the GTF Timing Standard, compute the
#=  * Stage 1 Parameters using the vertical refresh frequency.  In other
#=  * words: input a desired resolution and desired refresh rate, and
#=  * output the GTF mode timings.
#=  *
#=  * XXX All the code is in place to compute interlaced modes, but I don't
#=  * feel like testing it right now.
#=  *
#=  * XXX margin computations are implemented but not tested (nor used by
#=  * XFree86 of fbset mode descriptions, from what I can tell).
#=  */
#= 
#= mode *vert_refresh (int h_pixels, int v_lines, float freq,
#= 					int interlaced, int margins)
#= {
#= 	float h_pixels_rnd;
#= 	float v_lines_rnd;
#= 	float v_field_rate_rqd;
#= 	float top_margin;
#= 	float bottom_margin;
#= 	float interlace;
#= 	float h_period_est;
#= 	float vsync_plus_bp;
#= 	float v_back_porch;
#= 	float total_v_lines;
#= 	float v_field_rate_est;
#= 	float h_period;
#= 	float v_field_rate;
#= 	float v_frame_rate;
#= 	float left_margin;
#= 	float right_margin;
#= 	float total_active_pixels;
#= 	float ideal_duty_cycle;
#= 	float h_blank;
#= 	float total_pixels;
#= 	float pixel_freq;
#= 	float h_freq;
#= 
#= 	float h_sync;
#= 	float h_front_porch;
#= 	float v_odd_front_porch_lines;
#= 
#= 	mode *m = (mode*) malloc (sizeof (mode));
#= 	
#= 	
#= 	/*  1. In order to give correct results, the number of horizontal
#= 	 *  pixels requested is first processed to ensure that it is divisible
#= 	 *  by the character size, by rounding it to the nearest character
#= 	 *  cell boundary:
#= 	 *
#= 	 *  [H PIXELS RND] = ((ROUND([H PIXELS]/[CELL GRAN RND],0))*[CELLGRAN RND])
#= 	 */
#= 	
#= 	h_pixels_rnd = rint((float) h_pixels / CELL_GRAN) * CELL_GRAN;
#= 	
#= 	print_value(1, "[H PIXELS RND]", h_pixels_rnd);
#= 
#= 	
#= 	/*  2. If interlace is requested, the number of vertical lines assumed
#= 	 *  by the calculation must be halved, as the computation calculates
#= 	 *  the number of vertical lines per field. In either case, the
#= 	 *  number of lines is rounded to the nearest integer.
#= 	 *   
#= 	 *  [V LINES RND] = IF([INT RQD?]="y", ROUND([V LINES]/2,0),
#= 	 *                                     ROUND([V LINES],0))
#= 	 */
#= 
#= 	v_lines_rnd = interlaced ?
#= 			rint((float) v_lines) / 2.0 :
#= 			rint((float) v_lines);
#= 	
#= 	print_value(2, "[V LINES RND]", v_lines_rnd);
#= 	
#= 	
#= 	/*  3. Find the frame rate required:
#= 	 *
#= 	 *  [V FIELD RATE RQD] = IF([INT RQD?]="y", [I/P FREQ RQD]*2,
#= 	 *                                          [I/P FREQ RQD])
#= 	 */
#= 
#= 	v_field_rate_rqd = interlaced ? (freq * 2.0) : (freq);
#= 
#= 	print_value(3, "[V FIELD RATE RQD]", v_field_rate_rqd);
#= 	
#= 
#= 	/*  4. Find number of lines in Top margin:
#= 	 *
#= 	 *  [TOP MARGIN (LINES)] = IF([MARGINS RQD?]="Y",
#= 	 *          ROUND(([MARGIN%]/100*[V LINES RND]),0),
#= 	 *          0)
#= 	 */
#= 
#= 	top_margin = margins ? rint(MARGIN_PERCENT / 100.0 * v_lines_rnd) : (0.0);
#= 
#= 	print_value(4, "[TOP MARGIN (LINES)]", top_margin);
#= 	
#= 
#= 	/*  5. Find number of lines in Bottom margin:
#= 	 *
#= 	 *  [BOT MARGIN (LINES)] = IF([MARGINS RQD?]="Y",
#= 	 *          ROUND(([MARGIN%]/100*[V LINES RND]),0),
#= 	 *          0)
#= 	 */
#= 
#= 	bottom_margin = margins ? rint(MARGIN_PERCENT/100.0 * v_lines_rnd) : (0.0);
#= 
#= 	print_value(5, "[BOT MARGIN (LINES)]", bottom_margin);
#= 
#= 	
#= 	/*  6. If interlace is required, then set variable [INTERLACE]=0.5:
#= 	 *   
#= 	 *  [INTERLACE]=(IF([INT RQD?]="y",0.5,0))
#= 	 */
#= 
#= 	interlace = interlaced ? 0.5 : 0.0;
#= 
#= 	print_value(6, "[INTERLACE]", interlace);
#= 	
#= 
#= 	/*  7. Estimate the Horizontal period
#= 	 *
#= 	 *  [H PERIOD EST] = ((1/[V FIELD RATE RQD]) - [MIN VSYNC+BP]/1000000) /
#= 	 *                    ([V LINES RND] + (2*[TOP MARGIN (LINES)]) +
#= 	 *                     [MIN PORCH RND]+[INTERLACE]) * 1000000
#= 	 */
#= 
#= 	h_period_est = (((1.0/v_field_rate_rqd) - (MIN_VSYNC_PLUS_BP/1000000.0))
#= 					/ (v_lines_rnd + (2*top_margin) + MIN_PORCH + interlace)
#= 					* 1000000.0);
#= 
#= 	print_value(7, "[H PERIOD EST]", h_period_est);
#= 	
#= 
#= 	/*  8. Find the number of lines in V sync + back porch:
#= 	 *
#= 	 *  [V SYNC+BP] = ROUND(([MIN VSYNC+BP]/[H PERIOD EST]),0)
#= 	 */
#= 
#= 	vsync_plus_bp = rint(MIN_VSYNC_PLUS_BP/h_period_est);
#= 
#= 	print_value(8, "[V SYNC+BP]", vsync_plus_bp);
#= 	
#= 	
#= 	/*  9. Find the number of lines in V back porch alone:
#= 	 *
#= 	 *  [V BACK PORCH] = [V SYNC+BP] - [V SYNC RND]
#= 	 *
#= 	 *  XXX is "[V SYNC RND]" a typo? should be [V SYNC RQD]?
#= 	 */
#= 	
#= 	v_back_porch = vsync_plus_bp - V_SYNC_RQD;
#= 	
#= 	print_value(9, "[V BACK PORCH]", v_back_porch);
#= 	
#= 
#= 	/*  10. Find the total number of lines in Vertical field period:
#= 	 *
#= 	 *  [TOTAL V LINES] = [V LINES RND] + [TOP MARGIN (LINES)] +
#= 	 *                    [BOT MARGIN (LINES)] + [V SYNC+BP] + [INTERLACE] +
#= 	 *                    [MIN PORCH RND]
#= 	 */
#= 
#= 	total_v_lines = v_lines_rnd + top_margin + bottom_margin + vsync_plus_bp +
#= 		interlace + MIN_PORCH;
#= 	
#= 	print_value(10, "[TOTAL V LINES]", total_v_lines);
#= 	
#= 
#= 	/*  11. Estimate the Vertical field frequency:
#= 	 *
#= 	 *  [V FIELD RATE EST] = 1 / [H PERIOD EST] / [TOTAL V LINES] * 1000000
#= 	 */
#= 
#= 	v_field_rate_est = 1.0 / h_period_est / total_v_lines * 1000000.0;
#= 	
#= 	print_value(11, "[V FIELD RATE EST]", v_field_rate_est);
#= 	
#= 
#= 	/*  12. Find the actual horizontal period:
#= 	 *
#= 	 *  [H PERIOD] = [H PERIOD EST] / ([V FIELD RATE RQD] / [V FIELD RATE EST])
#= 	 */
#= 
#= 	h_period = h_period_est / (v_field_rate_rqd / v_field_rate_est);
#= 	
#= 	print_value(12, "[H PERIOD]", h_period);
#= 	
#= 
#= 	/*  13. Find the actual Vertical field frequency:
#= 	 *
#= 	 *  [V FIELD RATE] = 1 / [H PERIOD] / [TOTAL V LINES] * 1000000
#= 	 */
#= 
#= 	v_field_rate = 1.0 / h_period / total_v_lines * 1000000.0;
#= 
#= 	print_value(13, "[V FIELD RATE]", v_field_rate);
#= 	
#= 
#= 	/*  14. Find the Vertical frame frequency:
#= 	 *
#= 	 *  [V FRAME RATE] = (IF([INT RQD?]="y", [V FIELD RATE]/2, [V FIELD RATE]))
#= 	 */
#= 
#= 	v_frame_rate = interlaced ? v_field_rate / 2.0 : v_field_rate;
#= 
#= 	print_value(14, "[V FRAME RATE]", v_frame_rate);
#= 	
#= 
#= 	/*  15. Find number of pixels in left margin:
#= 	 *
#= 	 *  [LEFT MARGIN (PIXELS)] = (IF( [MARGINS RQD?]="Y",
#= 	 *          (ROUND( ([H PIXELS RND] * [MARGIN%] / 100 /
#= 	 *                   [CELL GRAN RND]),0)) * [CELL GRAN RND],
#= 	 *          0))
#= 	 */
#= 
#= 	left_margin = margins ?
#= 		rint(h_pixels_rnd * MARGIN_PERCENT / 100.0 / CELL_GRAN) * CELL_GRAN :
#= 		0.0;
#= 	
#= 	print_value(15, "[LEFT MARGIN (PIXELS)]", left_margin);
#= 	
#= 
#= 	/*  16. Find number of pixels in right margin:
#= 	 *
#= 	 *  [RIGHT MARGIN (PIXELS)] = (IF( [MARGINS RQD?]="Y",
#= 	 *          (ROUND( ([H PIXELS RND] * [MARGIN%] / 100 /
#= 	 *                   [CELL GRAN RND]),0)) * [CELL GRAN RND],
#= 	 *          0))
#= 	 */
#= 	
#= 	right_margin = margins ?
#= 		rint(h_pixels_rnd * MARGIN_PERCENT / 100.0 / CELL_GRAN) * CELL_GRAN :
#= 		0.0;
#= 	
#= 	print_value(16, "[RIGHT MARGIN (PIXELS)]", right_margin);
#= 	
#= 
#= 	/*  17. Find total number of active pixels in image and left and right
#= 	 *  margins:
#= 	 *
#= 	 *  [TOTAL ACTIVE PIXELS] = [H PIXELS RND] + [LEFT MARGIN (PIXELS)] +
#= 	 *                          [RIGHT MARGIN (PIXELS)]
#= 	 */
#= 
#= 	total_active_pixels = h_pixels_rnd + left_margin + right_margin;
#= 	
#= 	print_value(17, "[TOTAL ACTIVE PIXELS]", total_active_pixels);
#= 	
#= 	
#= 	/*  18. Find the ideal blanking duty cycle from the blanking duty cycle
#= 	 *  equation:
#= 	 *
#= 	 *  [IDEAL DUTY CYCLE] = [C'] - ([M']*[H PERIOD]/1000)
#= 	 */
#= 
#= 	ideal_duty_cycle = C_PRIME - (M_PRIME * h_period / 1000.0);
#= 	
#= 	print_value(18, "[IDEAL DUTY CYCLE]", ideal_duty_cycle);
#= 	
#= 
#= 	/*  19. Find the number of pixels in the blanking time to the nearest
#= 	 *  double character cell:
#= 	 *
#= 	 *  [H BLANK (PIXELS)] = (ROUND(([TOTAL ACTIVE PIXELS] *
#= 	 *                               [IDEAL DUTY CYCLE] /
#= 	 *                               (100-[IDEAL DUTY CYCLE]) /
#= 	 *                               (2*[CELL GRAN RND])), 0))
#= 	 *                       * (2*[CELL GRAN RND])
#= 	 */
#= 
#= 	h_blank = rint(total_active_pixels *
#= 				   ideal_duty_cycle /
#= 				   (100.0 - ideal_duty_cycle) /
#= 				   (2.0 * CELL_GRAN)) * (2.0 * CELL_GRAN);
#= 	
#= 	print_value(19, "[H BLANK (PIXELS)]", h_blank);
#= 	
#= 
#= 	/*  20. Find total number of pixels:
#= 	 *
#= 	 *  [TOTAL PIXELS] = [TOTAL ACTIVE PIXELS] + [H BLANK (PIXELS)]
#= 	 */
#= 
#= 	total_pixels = total_active_pixels + h_blank;
#= 	
#= 	print_value(20, "[TOTAL PIXELS]", total_pixels);
#= 	
#= 
#= 	/*  21. Find pixel clock frequency:
#= 	 *
#= 	 *  [PIXEL FREQ] = [TOTAL PIXELS] / [H PERIOD]
#= 	 */
#= 	
#= 	pixel_freq = total_pixels / h_period;
#= 	
#= 	print_value(21, "[PIXEL FREQ]", pixel_freq);
#= 	
#= 
#= 	/*  22. Find horizontal frequency:
#= 	 *
#= 	 *  [H FREQ] = 1000 / [H PERIOD]
#= 	 */
#= 
#= 	h_freq = 1000.0 / h_period;
#= 	
#= 	print_value(22, "[H FREQ]", h_freq);
#= 	
#= 
#= 
#= 	/* Stage 1 computations are now complete; I should really pass
#= 	   the results to another function and do the Stage 2
#= 	   computations, but I only need a few more values so I'll just
#= 	   append the computations here for now */
#= 
#= 	
#= 
#= 	/*  17. Find the number of pixels in the horizontal sync period:
#= 	 *
#= 	 *  [H SYNC (PIXELS)] =(ROUND(([H SYNC%] / 100 * [TOTAL PIXELS] /
#= 	 *                             [CELL GRAN RND]),0))*[CELL GRAN RND]
#= 	 */
#= 
#= 	h_sync = rint(H_SYNC_PERCENT/100.0 * total_pixels / CELL_GRAN) * CELL_GRAN;
#= 
#= 	print_value(17, "[H SYNC (PIXELS)]", h_sync);
#= 	
#= 
#= 	/*  18. Find the number of pixels in the horizontal front porch period:
#= 	 *
#= 	 *  [H FRONT PORCH (PIXELS)] = ([H BLANK (PIXELS)]/2)-[H SYNC (PIXELS)]
#= 	 */
#= 
#= 	h_front_porch = (h_blank / 2.0) - h_sync;
#= 
#= 	print_value(18, "[H FRONT PORCH (PIXELS)]", h_front_porch);
#= 	
#= 	
#= 	/*  36. Find the number of lines in the odd front porch period:
#= 	 *
#= 	 *  [V ODD FRONT PORCH(LINES)]=([MIN PORCH RND]+[INTERLACE])
#= 	 */
#= 	
#= 	v_odd_front_porch_lines = MIN_PORCH + interlace;
#= 	
#= 	print_value(36, "[V ODD FRONT PORCH(LINES)]", v_odd_front_porch_lines);
#= 	
#= 
#= 	/* finally, pack the results in the mode struct */
#= 	
#= 	m->hr  = (int) (h_pixels_rnd);
#= 	m->hss = (int) (h_pixels_rnd + h_front_porch);
#= 	m->hse = (int) (h_pixels_rnd + h_front_porch + h_sync);
#= 	m->hfl = (int) (total_pixels);
#= 
#= 	m->vr  = (int) (v_lines_rnd);
#= 	m->vss = (int) (v_lines_rnd + v_odd_front_porch_lines);
#= 	m->vse = (int) (int) (v_lines_rnd + v_odd_front_porch_lines + V_SYNC_RQD);
#= 	m->vfl = (int) (total_v_lines);
#= 
#= 	m->pclk   = pixel_freq;
#= 	m->h_freq = h_freq;
#= 	m->v_freq = freq;
#= 
#= 	return (m);
#= 	
#= } // vert_refresh()
#= 
#= 
#= 
#= 
#= /*
#=  * parse_command_line() - parse the command line and return an
#=  * alloced structure containing the results.  On error print usage
#=  * and return NULL.
#=  */ 
#= 
#= options *parse_command_line (int argc, char *argv[])
#= {
#= 	int n;
#= 
#= 	options *o = (options *) calloc (1, sizeof (options));
#= 
#= 	if (argc < 4) goto bad_option;
#= 
#= 	o->x = atoi (argv[1]);
#= 	o->y = atoi (argv[2]);
#= 	o->v_freq = atof (argv[3]);
#= 
#= 	/* XXX should check for errors in the above */
#= 	
#= 	n = 4;
#= 
#= 	while (n < argc) {
#= 		if ((strcmp (argv[n], "-v") == 0) ||
#= 			(strcmp (argv[n], "--verbose") == 0)) {
#= 			global_verbose = 1;
#= 		} else if ((strcmp (argv[n], "-f") == 0) ||
#= 				   (strcmp (argv[n], "--fbmode") == 0)) {
#= 			o->fbmode = 1;
#= 		} else if ((strcmp (argv[n], "-x") == 0) ||
#= 				   (strcmp (argv[n], "--xf86mode") == 0)) {
#= 			o->xf86mode = 1;
#= 		} else {
#= 			goto bad_option;
#= 		}
#= 		
#= 		n++;
#= 	}
#= 
#= 	/* if neither xf86mode nor fbmode were requested, default to
#= 	   xf86mode */
#= 
#= 	if (!o->fbmode && !o->xf86mode) o->xf86mode = 1;
#= 	
#= 	return (o);
#= 	
#=  bad_option:
#= 
#= 	fprintf (stderr, "\n");
#= 	fprintf (stderr, "usage: %s x y refresh [-v|--verbose] "
#= 			 "[-f|--fbmode] [-x|-xf86mode]\n", argv[0]);
#= 
#= 	fprintf (stderr, "\n");
#= 	
#= 	fprintf (stderr, "            x : the desired horizontal "
#= 			 "resolution (required)\n");
#= 	fprintf (stderr, "            y : the desired vertical "
#= 			 "resolution (required)\n");
#= 	fprintf (stderr, "      refresh : the desired refresh "
#= 			 "rate (required)\n");
#= 	fprintf (stderr, " -v|--verbose : enable verbose printouts "
#= 			 "(traces each step of the computation)\n");
#= 	fprintf (stderr, "  -f|--fbmode : output an fbset(8)-style mode "
#= 			 "description\n");
#= 	fprintf (stderr, " -x|-xf86mode : output an XFree86-style mode "
#= 			 "description (this is the default\n"
#= 			 "                if no mode description is requested)\n");
#= 	
#= 	fprintf (stderr, "\n");
#= 	
#= 	free (o);
#= 	return (NULL);
#= 
#= } // parse_command_line()
#= 
#= 
#= 
#= int main (int argc, char *argv[])
#= {
#= 	mode *m;
#= 	options *o;
#= 
#= 	o = parse_command_line (argc, argv);
#= 	if (!o) exit (1);
#= 	
#= 	m = vert_refresh (o->x, o->y, o->v_freq, 0, 0);
#= 	if (!m) exit (1);
#= 
#= 	if (o->xf86mode)
#= 		print_xf86_mode(m);
#= 	
#= 	if (o->fbmode)
#= 		print_fb_mode(m);
#= 	
#= 	return 0;
#= 	
#= } // main()