/* (c) 2021 Aaron Taylor <ataylor at subgeniuskitty dot com> */
/* See LICENSE.txt file for copyright and license details. */
-// TODO:
-// - Write a brief description of the machine being simulated. Only one thread, reduced RAM, no meaningful console when running as screensaver, etc.
-
-// Ideas for sample programs to include:
-// - Build list of integers on the stack (DUP, IM_1, ADD).
-// - Calculate prime numbers, placing them on the stack.
-// - Lights sliding back and forth, like PDP-11 front panel with some OSes.
-
#include "screenhack.h"
#include "simulator.h"
-/* Keep this source code C89 compliant per XScreensaver's instructions. */
+/* -------------------------------------------------------------------------- */
+/* Front Panel Layout */
+/* -------------------------------------------------------------------------- */
+
+// All of these values are in units of 'cells', not 'pixels'. Where applicable,
+// coordinates refer to the upper-left corner of a cell. See the files
+// `layout_reference.*` for details.
+
+#define OVERALL_WIDTH_IN_CELLS 70
+#define HEADER_HEIGHT_IN_CELLS 14
+#define FOOTER_HEIGHT_IN_CELLS 2
+
+#define LOGO_X_OFFSET 2
+#define LOGO_Y_OFFSET 2
+#define LOGO_WIDTH 20
+#define LOGO_NAME_HEIGHT 6
+#define LOGO_WEBSITE_HEIGHT 2
+
+#define HALT_X_OFFSET 26
+#define HALT_Y_OFFSET 2
+#define HALT_WIDTH 6
+#define HALT_LIGHT_HEIGHT 6
+#define HALT_LABEL_HEIGHT 2
+
+#define WORDLINE_BITS_PER_STRIPE 4
+#define WORDLINE_WIDTH 32
+#define WORDLINE_HEIGHT 1
+
+#define PC_X_OFFSET 36
+#define PC_Y_OFFSET 7
+#define PC_WIDTH 32
+#define PC_LABEL_HEIGHT 2
+#define PC_LIGHT_HEIGHT 1
+
+#define SC_X_OFFSET 42
+#define SC_Y_OFFSET 2
+#define SC_WIDTH 5
+#define SC_LABEL_HEIGHT 2
+#define SC_LIGHT_HEIGHT 1
+
+#define PSW_N_X_OFFSET 51
+#define PSW_Z_X_OFFSET 58
+#define PSW_Y_OFFSET 2
+#define PSW_LABEL_WIDTH 3
+#define PSW_LABEL_HEIGHT 2
+#define PSW_LIGHT_WIDTH 1
+#define PSW_LIGHT_HEIGHT 1
+
+#define STACK_X_OFFSET 2
+#define STACK_Y_OFFSET 12
+#define STACK_WIDTH 32
+#define STACK_LABEL_HEIGHT 2
+#define STACK_LIGHT_HEIGHT 1
+
+#define HEAP_X_OFFSET 36
+#define HEAP_Y_OFFSET 12
+#define HEAP_WIDTH 32
+#define HEAP_LABEL_HEIGHT 2
+#define HEAP_LIGHT_HEIGHT 1
/* -------------------------------------------------------------------------- */
/* Data Structures */
/* -------------------------------------------------------------------------- */
struct NEDsim {
- /* Various X resources */
+ // Various X resources
Display * dpy;
Window win;
GC gc;
- // TODO: Explain these
+ // Tracks the width and height (in pixels) of 'win' on 'dpy'.
int dpy_width, dpy_height;
- // TODO: Explain that this is created during init, then lights are populated/overwritten on each frame.
+ // To ensure the NED display is always synchronized/valid, we
+ // double-buffer. This is that buffer.
Pixmap panel;
- /* Delay (in microseconds) between clock cycles in the NED CPU. */
- size_t delay;
-
+ // The front panel is defined in a fixed grid of 'cells' which are then
+ // scaled and projected onto the actual screen. This variable tracks the
+ // size of one 'cell' in screen pixels.
int cell_size;
+ // Like above, this variable tracks the scaled size (in pixels) of cell
+ // borders when projecting them on the screen.
int border_size;
+
+ // Since the panel will be smaller than the display window, these two
+ // variable track the location (in pixels) of the upper left corner of the
+ // NED panel (pretending it didn't have rounded corners) relative to the
+ // display window's origin.
int origin_x_offset, origin_y_offset;
+
+ // Delay (in microseconds) between clock cycles in the NED CPU.
+ size_t delay;
+
+ // Since the heap and stack areas are resized to fit the display, this
+ // variable tracks their height.
int num_data_rows;
+ // This is an index into the color_list[] array, selecting a color scheme.
size_t color_index;
+ // If the display is unsuitable (e.g. too small), this boolean is 'true'.
+ // With this, we blank the display but keep the simulation itself running,
+ // allowing the ongoing simulation to display when the situation is
+ // corrected, and allowing us to avoid boring the user with unnecessary
+ // simulation restarts.
Bool suitable_display;
+ // The font size is dynamically adjusted based on display size. This
+ // variable stores the full font description, including the correct font
+ // size, all in the X11 font specifier format. For example,
+ // -*-helvetica-*-r-*-*-72-*-*-*-*-*-*-*
+ // if the display were using a 72 point helvetica font without emphasis.
char * current_font;
- // TODO: Explain that this contains all the actual state of the NED machine being simulated.
+ // This struct contains all machine state for the simulated NED computer.
struct NEDstate * nedstate;
};
struct color_rgb {
- // TODO: Explain why this is an unsigned short. Copy from WolframAutomata.
+ // The type 'unsigned short' comes from the XColor struct definition.
+ // The red, green, and blue values are always in the range 0 to 65535
+ // inclusive, independent of the number of bits actually used in the
+ // display hardware. The server scales these values to the range used
+ // by the hardware. Black is represented by (0,0,0), and white is
+ // represented by (65535,65535,65535).
unsigned short red, green, blue;
};
struct color_scheme {
- // TODO: Explain all this.
+ // The following entries define a full color scheme for a NED panel.
struct color_rgb
- panel_bg,
- panel_fg,
- light_on,
- light_off,
- error_on,
- error_off,
- primary,
- secondary,
- tertiary,
- border,
- text;
+ panel_bg, // Empty screen space not taken up by the panel
+ panel_fg, // Panel body/faceplate
+ light_on, // Illuminated data indicator
+ light_off, // Non-illuminated data indicator
+ error_on, // Illuminated error indicator
+ error_off, // Non-illuminated error indicator
+ primary, // Primary panel color (see: logo background)
+ secondary, // Secondary panel color (see: "HALT" text background)
+ tertiary, // Tertiary panel color (see: "subgeniuskitty.com" text background)
+ border, // Cell borders
+ text; // Panel text
};
-//static struct color_scheme color_list[] = {
-// // TODO: Explain all this.
-// // TODO: Add other color schemes, like purple PDP-11/70.
-// // TODO: http://www.chdickman.com/pdp8/DECcolors/
-// {
-// {63479,63479,63479}, // 092-XXXX-123
-// { 5140, 2056, 5654}, // 092-XXXX-152
-// {40092,11051,15677}, // 092-XXXX-139
-// {30326,13107,12850}, // 092-XXXX-154
-// {65535,13107,12850}, // homemade
-// {30326,13107,12850}, // 092-XXXX-154
-// { 4112,12850,20046}, // 092-XXXX-145
-// {12336,29555,37008}, // 092-XXXX-151
-// {30326,24158, 6425}, // 092-XXXX-157
-// {63479,63479,63479}, // 092-XXXX-123
-// {63479,63479,63479} // 092-XXXX-123
-// }
-//};
-
+// All included color schemes for NEDsim are defined in this array. To select a
+// particular color scheme at runtime, use the `-color N` CLI option.
static struct color_scheme color_list[] = {
- // TODO: Explain all this.
- // TODO: Add other color schemes, like purple PDP-11/70.
- // TODO: http://www.chdickman.com/pdp8/DECcolors/
- {
+ { // This color scheme is inspired by the KI10 version of the PDP-10.
+ // Many RGB values came from: http://www.chdickman.com/pdp8/DECcolors/
{63479,63479,63479}, // 092-XXXX-123
{ 5140, 2056, 5654}, // 092-XXXX-152
- {65535,11051,15677}, // 092-XXXX-139 - edit
- {20000,13107,12850}, // 092-XXXX-154 - edit
- {65535,13107,12850}, // homemade
- {20000,13107,12850}, // 092-XXXX-154 - edit
+ {65535,11051,15677}, // homemade, derived from 092-XXXX-139
+ {20000,13107,12850}, // homemade, derived from 092-XXXX-154
+ {65535,13107,12850}, // homemade, derived from 092-XXXX-154
+ {20000,13107,12850}, // homemade, derived from 092-XXXX-154
{ 4112,12850,20046}, // 092-XXXX-145
{12336,29555,37008}, // 092-XXXX-151
{30326,24158, 6425}, // 092-XXXX-157
{63479,63479,63479}, // 092-XXXX-123
{63479,63479,63479} // 092-XXXX-123
+ },
+ { // This color scheme is (very loosely) inspired by the first version of the PDP-11/70.
+ // Many RGB values came from: http://www.chdickman.com/pdp8/DECcolors/
+ {63479,63479,63479}, // 092-XXXX-123
+ { 5140, 2056, 5654}, // 092-XXXX-152
+ {51400,34952,26682}, // homemade, derived from 092-XXXX-136
+ {20000,13107,12850}, // homemade, derived from 092-XXXX-154
+ {65535,13107,12850}, // homemade, derived from 092-XXXX-154
+ {20000,13107,12850}, // homemade, derived from 092-XXXX-154
+ {28270, 8995,19532}, // 092-XXXX-140
+ {40092,11051,15677}, // 092-XXXX-139
+ {15000,21000, 4000}, // homemade, derived from 092-XXXX-129
+ {63479,63479,63479}, // 092-XXXX-123
+ {63479,63479,63479} // 092-XXXX-123
}
};
/* Helper Functions */
/* -------------------------------------------------------------------------- */
-// TODO: Explain
+// Set foreground color for the current graphics context.
static void
set_color(struct NEDsim * nedsim, struct color_rgb * color)
{
XSetForeground(nedsim->dpy, nedsim->gc, temp.pixel);
}
-// TODO: Explain
// TODO: Make this a lot faster.
-// Input: size in 'cells', and sets font to fill that size, minus border and padding room.
+// Set font size to fill 'size' cells vertically, minus space for border and padding.
static void
set_font_size(struct NEDsim * nedsim, int size)
{
nedsim->current_font = font_full_name;
}
-// TODO: Explain
-// TODO: Explain that this returns result in pixels so we can track fractional cell usage.
+// Unlike most functions in this program that input/output in units of 'cells',
+// this function uses units of 'pixels' so the caller can track fractional cell
+// usage (e.g. for centering the text).
static void
get_text_size(struct NEDsim * nedsim, const char * text, int * x_size, int * y_size)
{
*y_size = overall.ascent - overall.descent;
}
-// TODO: Explain
-// TODO: Note that this might leave the foreground color changed.
-// Argument coordinates are in 'cells', not pixels.
+// When specifying the rectangular area to draw, all coordinates and sizes are
+// in units of 'cells'. Also, be aware that this function alters the
+// foreground color.
static void
draw_rect_area(struct NEDsim * nedsim, size_t x_origin, size_t y_origin, size_t x_size, size_t y_size,
Bool bord_top, Bool bord_bottom, Bool bord_left, Bool bord_right)
{
+ // First fill in the rectangular area...
x_origin *= nedsim->cell_size;
x_origin += nedsim->origin_x_offset;
y_origin *= nedsim->cell_size;
y_origin += nedsim->origin_y_offset;
x_size *= nedsim->cell_size;
y_size *= nedsim->cell_size;
- XFillRectangle(nedsim->dpy, nedsim->win, nedsim->gc, x_origin, y_origin, x_size, y_size);
+ XFillRectangle(nedsim->dpy, nedsim->panel, nedsim->gc, x_origin, y_origin, x_size, y_size);
+ // ...then give it a border, if requested.
set_color(nedsim, &color_list[nedsim->color_index].border);
if (bord_top) {
- XFillRectangle(nedsim->dpy, nedsim->win, nedsim->gc, x_origin, y_origin, x_size, nedsim->border_size);
+ XFillRectangle(nedsim->dpy, nedsim->panel, nedsim->gc,
+ x_origin, y_origin, x_size, nedsim->border_size);
}
if (bord_bottom) {
- XFillRectangle(nedsim->dpy, nedsim->win, nedsim->gc, x_origin, (y_origin + y_size - nedsim->border_size), x_size, nedsim->border_size);
+ XFillRectangle(nedsim->dpy, nedsim->panel, nedsim->gc,
+ x_origin, (y_origin + y_size - nedsim->border_size), x_size, nedsim->border_size);
}
if (bord_left) {
- XFillRectangle(nedsim->dpy, nedsim->win, nedsim->gc, x_origin, y_origin, nedsim->border_size, y_size);
+ XFillRectangle(nedsim->dpy, nedsim->panel, nedsim->gc,
+ x_origin, y_origin, nedsim->border_size, y_size);
}
if (bord_right) {
- XFillRectangle(nedsim->dpy, nedsim->win, nedsim->gc, (x_origin + x_size - nedsim->border_size), y_origin, nedsim->border_size, y_size);
+ XFillRectangle(nedsim->dpy, nedsim->panel, nedsim->gc,
+ (x_origin + x_size - nedsim->border_size), y_origin, nedsim->border_size, y_size);
}
}
-// TODO: Explain
-// Arguments are in units of 'cells', not pixels.
-// Will leave foreground color changed.
-// Draws filled circle with upper left corner at x,y.
+// Draws filled circle in a square area with upper left corner at x,y. When
+// specifying the location and size to draw, all values are in units of
+// 'cells'. Also, be aware that this function alters the foreground color.
static void
draw_circular_area(struct NEDsim * nedsim, size_t x, size_t y, double diameter)
{
y -= (0.5 * nedsim->border_size);
// Start angle 0 and ending angle 360*64 is one full circle in Xlib units.
- XFillArc(nedsim->dpy, nedsim->win, nedsim->gc, x, y, diameter, diameter, 0, 360*64);
+ XFillArc(nedsim->dpy, nedsim->panel, nedsim->gc, x, y, diameter, diameter, 0, 360*64);
}
-// TODO: Explain
+// Draws the panel itself. Not the lights/labels/etc, but the flat sheet of
+// metal that is the front panel.
static void
draw_panel(struct NEDsim * nedsim)
{
-// TODO: Collect all relevant #defines somewhere.
-#define OVERALL_WIDTH_IN_CELLS 70
-#define HEADER_HEIGHT_IN_CELLS 14
-#define FOOTER_HEIGHT_IN_CELLS 2
-
// Draw background color over entire window.
set_color(nedsim, &color_list[nedsim->color_index].panel_bg);
- XFillRectangle(nedsim->dpy, nedsim->win, nedsim->gc, 0, 0, nedsim->dpy_width, nedsim->dpy_height);
+ XFillRectangle(nedsim->dpy, nedsim->panel, nedsim->gc, 0, 0, nedsim->dpy_width, nedsim->dpy_height);
// Draw NED panel in foreground color.
set_color(nedsim, &color_list[nedsim->color_index].panel_fg);
- XFillRectangle(nedsim->dpy, nedsim->win, nedsim->gc,
+ XFillRectangle(nedsim->dpy, nedsim->panel, nedsim->gc,
nedsim->origin_x_offset,
nedsim->origin_y_offset,
nedsim->cell_size * OVERALL_WIDTH_IN_CELLS,
// Give the panel rounded corners by first deleting the four right-angle corners...
set_color(nedsim, &color_list[nedsim->color_index].panel_bg);
- XFillRectangle(nedsim->dpy, nedsim->win, nedsim->gc,
+ XFillRectangle(nedsim->dpy, nedsim->panel, nedsim->gc,
nedsim->origin_x_offset,
nedsim->origin_y_offset,
nedsim->cell_size,
nedsim->cell_size
);
- XFillRectangle(nedsim->dpy, nedsim->win, nedsim->gc,
+ XFillRectangle(nedsim->dpy, nedsim->panel, nedsim->gc,
nedsim->origin_x_offset + (nedsim->cell_size * (OVERALL_WIDTH_IN_CELLS-1)),
nedsim->origin_y_offset,
nedsim->cell_size,
nedsim->cell_size
);
- XFillRectangle(nedsim->dpy, nedsim->win, nedsim->gc,
+ XFillRectangle(nedsim->dpy, nedsim->panel, nedsim->gc,
nedsim->origin_x_offset,
nedsim->origin_y_offset + (nedsim->cell_size * (HEADER_HEIGHT_IN_CELLS + nedsim->num_data_rows + FOOTER_HEIGHT_IN_CELLS - 1)),
nedsim->cell_size,
nedsim->cell_size
);
- XFillRectangle(nedsim->dpy, nedsim->win, nedsim->gc,
+ XFillRectangle(nedsim->dpy, nedsim->panel, nedsim->gc,
nedsim->origin_x_offset + (nedsim->cell_size * (OVERALL_WIDTH_IN_CELLS-1)),
nedsim->origin_y_offset + (nedsim->cell_size * (HEADER_HEIGHT_IN_CELLS + nedsim->num_data_rows + FOOTER_HEIGHT_IN_CELLS - 1)),
nedsim->cell_size,
);
// ...and then replacing them with filled arcs, forming rounded corners.
set_color(nedsim, &color_list[nedsim->color_index].panel_fg);
- XFillArc(nedsim->dpy, nedsim->win, nedsim->gc,
+ XFillArc(nedsim->dpy, nedsim->panel, nedsim->gc,
nedsim->origin_x_offset,
nedsim->origin_y_offset,
nedsim->cell_size * 2, nedsim->cell_size * 2,
180*64, -90*64
);
- XFillArc(nedsim->dpy, nedsim->win, nedsim->gc,
+ XFillArc(nedsim->dpy, nedsim->panel, nedsim->gc,
nedsim->origin_x_offset + (nedsim->cell_size * (OVERALL_WIDTH_IN_CELLS-2)),
nedsim->origin_y_offset,
nedsim->cell_size * 2, nedsim->cell_size * 2,
0, 90*64
);
- XFillArc(nedsim->dpy, nedsim->win, nedsim->gc,
+ XFillArc(nedsim->dpy, nedsim->panel, nedsim->gc,
nedsim->origin_x_offset,
nedsim->origin_y_offset + (nedsim->cell_size * (HEADER_HEIGHT_IN_CELLS + nedsim->num_data_rows + FOOTER_HEIGHT_IN_CELLS - 2)),
nedsim->cell_size * 2, nedsim->cell_size * 2,
180*64, 90*64
);
- XFillArc(nedsim->dpy, nedsim->win, nedsim->gc,
+ XFillArc(nedsim->dpy, nedsim->panel, nedsim->gc,
nedsim->origin_x_offset + (nedsim->cell_size * (OVERALL_WIDTH_IN_CELLS-2)),
nedsim->origin_y_offset + (nedsim->cell_size * (HEADER_HEIGHT_IN_CELLS + nedsim->num_data_rows + FOOTER_HEIGHT_IN_CELLS - 2)),
nedsim->cell_size * 2, nedsim->cell_size * 2,
);
}
-// TODO: Explain
+// Draw the "NED" and "subgeniuskitty.com" logos on the front panel.
static void
draw_logo(struct NEDsim * nedsim)
{
-#define LOGO_X_OFFSET 2
-#define LOGO_Y_OFFSET 2
-#define LOGO_WIDTH 20
-#define LOGO_NAME_HEIGHT 6
-#define LOGO_WEBSITE_HEIGHT 2
-
// First draw the two colored boxes that comprise the logo area.
set_color(nedsim, &color_list[nedsim->color_index].primary);
draw_rect_area(nedsim, LOGO_X_OFFSET, LOGO_Y_OFFSET, LOGO_WIDTH, LOGO_NAME_HEIGHT, True, True, False, False);
get_text_size(nedsim, "NED", &text_x_size, &text_y_size);
int local_x_offset = ((LOGO_WIDTH * nedsim->cell_size) - text_x_size) / 2;
int local_y_offset = ((LOGO_NAME_HEIGHT * nedsim->cell_size) - text_y_size) / 2;
- XDrawString(nedsim->dpy, nedsim->win, nedsim->gc, (LOGO_X_OFFSET * nedsim->cell_size + nedsim->origin_x_offset + local_x_offset),
+ XDrawString(nedsim->dpy, nedsim->panel, nedsim->gc, (LOGO_X_OFFSET * nedsim->cell_size + nedsim->origin_x_offset + local_x_offset),
((LOGO_Y_OFFSET+LOGO_NAME_HEIGHT) * nedsim->cell_size + nedsim->origin_y_offset - local_y_offset), "NED", 3);
// And draw the 'subgeniuskitty.com' text in the bottom box.
get_text_size(nedsim, "subgeniuskitty.com", &text_x_size, &text_y_size);
local_x_offset = ((LOGO_WIDTH * nedsim->cell_size) - text_x_size) / 2;
local_y_offset = ((LOGO_WEBSITE_HEIGHT * nedsim->cell_size) - text_y_size) / 2;
- XDrawString(nedsim->dpy, nedsim->win, nedsim->gc, (LOGO_X_OFFSET * nedsim->cell_size + nedsim->origin_x_offset + local_x_offset),
+ XDrawString(nedsim->dpy, nedsim->panel, nedsim->gc, (LOGO_X_OFFSET * nedsim->cell_size + nedsim->origin_x_offset + local_x_offset),
((LOGO_Y_OFFSET+LOGO_NAME_HEIGHT+LOGO_WEBSITE_HEIGHT) * nedsim->cell_size + nedsim->origin_y_offset - local_y_offset), "subgeniuskitty.com", 18);
}
-// TODO: Explain
+// Draw the HALT indicator area on the front panel.
static void
draw_halt(struct NEDsim * nedsim)
{
-#define HALT_X_OFFSET 26
-#define HALT_Y_OFFSET 2
-#define HALT_WIDTH 6
-#define HALT_LIGHT_HEIGHT 6
-#define HALT_LABEL_HEIGHT 2
-
// First draw the two colored boxes that comprise the halt area.
set_color(nedsim, &color_list[nedsim->color_index].tertiary);
draw_rect_area(nedsim, HALT_X_OFFSET, HALT_Y_OFFSET, HALT_WIDTH, HALT_LIGHT_HEIGHT, True, True, False, False);
get_text_size(nedsim, "HALT", &text_x_size, &text_y_size);
int local_x_offset = ((HALT_WIDTH * nedsim->cell_size) - text_x_size) / 2;
int local_y_offset = ((HALT_LABEL_HEIGHT * nedsim->cell_size) - text_y_size) / 2;
- XDrawString(nedsim->dpy, nedsim->win, nedsim->gc, (HALT_X_OFFSET * nedsim->cell_size + nedsim->origin_x_offset + local_x_offset),
+ XDrawString(nedsim->dpy, nedsim->panel, nedsim->gc, (HALT_X_OFFSET * nedsim->cell_size + nedsim->origin_x_offset + local_x_offset),
((HALT_Y_OFFSET+HALT_LIGHT_HEIGHT+HALT_LABEL_HEIGHT) * nedsim->cell_size + nedsim->origin_y_offset - local_y_offset), "HALT", 4);
}
-// TODO: Explain
+// Draw the 32 lights corresponding to 'word' at coordinates ('x','y').
+// Note that this function ONLY draws the lights and is used each frame for
+// updating the panel. To draw the wordline area itself, use draw_wordline().
static void
draw_wordline_lights(struct NEDsim * nedsim, uint32_t word, int x, int y)
{
-#define WORDLINE_BITS_PER_STRIPE 4
-#define WORDLINE_WIDTH 32
-#define WORDLINE_HEIGHT 1
-
for (int i = 0; i < WORDLINE_WIDTH; i++) {
if (word & (1<<(WORDLINE_WIDTH-1-i))) {
set_color(nedsim, &color_list[nedsim->color_index].light_on);
}
}
-// TODO: Explain
+// Draw a single 32-bit NED word line at coordinates ('x','y').
+// Note that this draws a wordline with value 0. To update with a specific
+// value, call draw_wordline_lights() after drawing the wordline area at least
+// once.
static void
draw_wordline(struct NEDsim * nedsim, int x, int y)
{
draw_wordline_lights(nedsim, 0, x, y);
}
-// TODO: Explain
+// Draw the Program Counter area (but don't populate it yet).
static void
draw_pc(struct NEDsim * nedsim)
{
-// TODO: Note that all #defines use units of 'cells', not 'pixels', etc.
-#define PC_X_OFFSET 36
-#define PC_Y_OFFSET 7
-#define PC_WIDTH 32
-#define PC_LABEL_HEIGHT 2
-#define PC_LIGHT_HEIGHT 1
-
// First draw the two colored boxes that comprise the PC area.
set_color(nedsim, &color_list[nedsim->color_index].tertiary);
draw_rect_area(nedsim, PC_X_OFFSET, PC_Y_OFFSET, PC_WIDTH, PC_LABEL_HEIGHT, True, True, False, False);
get_text_size(nedsim, "PC", &text_x_size, &text_y_size);
int local_x_offset = ((PC_WIDTH * nedsim->cell_size) - text_x_size) / 2;
int local_y_offset = ((PC_LABEL_HEIGHT * nedsim->cell_size) - text_y_size) / 2;
- XDrawString(nedsim->dpy, nedsim->win, nedsim->gc, (PC_X_OFFSET * nedsim->cell_size + nedsim->origin_x_offset + local_x_offset),
+ XDrawString(nedsim->dpy, nedsim->panel, nedsim->gc, (PC_X_OFFSET * nedsim->cell_size + nedsim->origin_x_offset + local_x_offset),
((PC_Y_OFFSET+PC_LABEL_HEIGHT) * nedsim->cell_size + nedsim->origin_y_offset - local_y_offset), "PC", 2);
}
-// TODO: Explain
+// Draw the Stack Counter area (but don't populate it yet).
static void
draw_sc(struct NEDsim * nedsim)
{
-#define SC_X_OFFSET 42
-#define SC_Y_OFFSET 2
-#define SC_WIDTH 5
-#define SC_LABEL_HEIGHT 2
-#define SC_LIGHT_HEIGHT 1
-
// First draw the two colored boxes that comprise the SC area.
set_color(nedsim, &color_list[nedsim->color_index].secondary);
draw_rect_area(nedsim, SC_X_OFFSET, SC_Y_OFFSET, SC_WIDTH, SC_LABEL_HEIGHT, True, True, False, False);
get_text_size(nedsim, "SC", &text_x_size, &text_y_size);
int local_x_offset = ((SC_WIDTH * nedsim->cell_size) - text_x_size) / 2;
int local_y_offset = ((SC_LABEL_HEIGHT * nedsim->cell_size) - text_y_size) / 2;
- XDrawString(nedsim->dpy, nedsim->win, nedsim->gc, (SC_X_OFFSET * nedsim->cell_size + nedsim->origin_x_offset + local_x_offset),
+ XDrawString(nedsim->dpy, nedsim->panel, nedsim->gc, (SC_X_OFFSET * nedsim->cell_size + nedsim->origin_x_offset + local_x_offset),
((SC_Y_OFFSET+SC_LABEL_HEIGHT) * nedsim->cell_size + nedsim->origin_y_offset - local_y_offset), "SC", 2);
}
-// TODO: Explain
+// Draw areas for the two PSW flags, 'Z'ero and 'N'egative.
static void
draw_psw(struct NEDsim * nedsim)
{
-#define PSW_N_X_OFFSET 51
-#define PSW_Z_X_OFFSET 58
-#define PSW_Y_OFFSET 2
-#define PSW_LABEL_WIDTH 3
-#define PSW_LABEL_HEIGHT 2
-#define PSW_LIGHT_WIDTH 1
-#define PSW_LIGHT_HEIGHT 1
-
// First draw the four colored boxes that comprise the two PSW areas.
set_color(nedsim, &color_list[nedsim->color_index].secondary);
draw_rect_area(nedsim, PSW_N_X_OFFSET, PSW_Y_OFFSET, PSW_LABEL_WIDTH, PSW_LABEL_HEIGHT, True, True, False, False);
get_text_size(nedsim, "N", &text_x_size, &text_y_size);
int local_x_offset = ((PSW_LABEL_WIDTH * nedsim->cell_size) - text_x_size) / 2;
int local_y_offset = ((PSW_LABEL_HEIGHT * nedsim->cell_size) - text_y_size) / 2;
- XDrawString(nedsim->dpy, nedsim->win, nedsim->gc, (PSW_N_X_OFFSET * nedsim->cell_size + nedsim->origin_x_offset + local_x_offset),
+ XDrawString(nedsim->dpy, nedsim->panel, nedsim->gc, (PSW_N_X_OFFSET * nedsim->cell_size + nedsim->origin_x_offset + local_x_offset),
((PSW_Y_OFFSET+PSW_LABEL_HEIGHT) * nedsim->cell_size + nedsim->origin_y_offset - local_y_offset), "N", 1);
// Now draw the label text "Z".
get_text_size(nedsim, "Z", &text_x_size, &text_y_size);
local_x_offset = ((PSW_LABEL_WIDTH * nedsim->cell_size) - text_x_size) / 2;
local_y_offset = ((PSW_LABEL_HEIGHT * nedsim->cell_size) - text_y_size) / 2;
- XDrawString(nedsim->dpy, nedsim->win, nedsim->gc, (PSW_Z_X_OFFSET * nedsim->cell_size + nedsim->origin_x_offset + local_x_offset),
+ XDrawString(nedsim->dpy, nedsim->panel, nedsim->gc, (PSW_Z_X_OFFSET * nedsim->cell_size + nedsim->origin_x_offset + local_x_offset),
((PSW_Y_OFFSET+PSW_LABEL_HEIGHT) * nedsim->cell_size + nedsim->origin_y_offset - local_y_offset), "Z", 1);
}
-// TODO: Explain
+// Draw the stack area (but don't populate it yet).
static void
draw_stack(struct NEDsim * nedsim)
{
-#define STACK_X_OFFSET 2
-#define STACK_Y_OFFSET 12
-#define STACK_WIDTH 32
-#define STACK_LABEL_HEIGHT 2
-#define STACK_LIGHT_HEIGHT 1
-
// First draw the two colored boxes that comprise the stack area.
set_color(nedsim, &color_list[nedsim->color_index].tertiary);
draw_rect_area(nedsim, STACK_X_OFFSET, STACK_Y_OFFSET, STACK_WIDTH, STACK_LABEL_HEIGHT, True, True, False, False);
int text_x_size, text_y_size;
get_text_size(nedsim, "Stack Size:", &text_x_size, &text_y_size);
int local_y_offset = ((STACK_LABEL_HEIGHT * nedsim->cell_size) - text_y_size) / 2;
- XDrawString(nedsim->dpy, nedsim->win, nedsim->gc, ((STACK_X_OFFSET + 1) * nedsim->cell_size + nedsim->origin_x_offset),
+ XDrawString(nedsim->dpy, nedsim->panel, nedsim->gc, ((STACK_X_OFFSET + 1) * nedsim->cell_size + nedsim->origin_x_offset),
((STACK_Y_OFFSET+STACK_LABEL_HEIGHT) * nedsim->cell_size + nedsim->origin_y_offset - local_y_offset), "Stack Size:", 11);
}
-// TODO: Explain
+// Draw the heap area (but don't populate it yet).
static void
draw_heap(struct NEDsim * nedsim)
{
-#define HEAP_X_OFFSET 36
-#define HEAP_Y_OFFSET 12
-#define HEAP_WIDTH 32
-#define HEAP_LABEL_HEIGHT 2
-#define HEAP_LIGHT_HEIGHT 1
// TODO: What should I do about this define? I would like to be able to specify the address so I can do things like display the code itself if nothign interesting happens in RAM.
#define HEAP_START_ADDRESS 0x20000000
int text_x_size, text_y_size;
get_text_size(nedsim, "RAM Base:", &text_x_size, &text_y_size);
int local_y_offset = ((HEAP_LABEL_HEIGHT * nedsim->cell_size) - text_y_size) / 2;
- XDrawString(nedsim->dpy, nedsim->win, nedsim->gc, ((HEAP_X_OFFSET + 1) * nedsim->cell_size + nedsim->origin_x_offset),
+ XDrawString(nedsim->dpy, nedsim->panel, nedsim->gc, ((HEAP_X_OFFSET + 1) * nedsim->cell_size + nedsim->origin_x_offset),
((HEAP_Y_OFFSET+HEAP_LABEL_HEIGHT) * nedsim->cell_size + nedsim->origin_y_offset - local_y_offset), "RAM Base:", 9);
// Now draw the address text.
snprintf(address, sizeof(address), "0x%08X", HEAP_START_ADDRESS);
get_text_size(nedsim, address, &text_x_size, &text_y_size);
local_y_offset = ((HEAP_LABEL_HEIGHT * nedsim->cell_size) - text_y_size) / 2;
- XDrawString(nedsim->dpy, nedsim->win, nedsim->gc, ((HEAP_X_OFFSET + 1 + (HEAP_WIDTH / 2)) * nedsim->cell_size + nedsim->origin_x_offset),
+ XDrawString(nedsim->dpy, nedsim->panel, nedsim->gc, ((HEAP_X_OFFSET + 1 + (HEAP_WIDTH / 2)) * nedsim->cell_size + nedsim->origin_x_offset),
((HEAP_Y_OFFSET+HEAP_LABEL_HEIGHT) * nedsim->cell_size + nedsim->origin_y_offset - local_y_offset), address, strlen(address));
}
-// TODO: Explain
+// After the static front panel has been drawn at least once, this function
+// updates all the dynamic parts of the panel (lights + text values) and is
+// called every frame.
static void
update_display(struct NEDsim * nedsim)
{
int text_x_size, text_y_size;
get_text_size(nedsim, stack_size, &text_x_size, &text_y_size);
int local_y_offset = ((STACK_LABEL_HEIGHT * nedsim->cell_size) - text_y_size) / 2;
- XDrawString(nedsim->dpy, nedsim->win, nedsim->gc, ((STACK_X_OFFSET + 1 + (STACK_WIDTH / 2)) * nedsim->cell_size + nedsim->origin_x_offset),
+ XDrawString(nedsim->dpy, nedsim->panel, nedsim->gc, ((STACK_X_OFFSET + 1 + (STACK_WIDTH / 2)) * nedsim->cell_size + nedsim->origin_x_offset),
((STACK_Y_OFFSET+STACK_LABEL_HEIGHT) * nedsim->cell_size + nedsim->origin_y_offset - local_y_offset), stack_size, strlen(stack_size));
// Draw the heap lights.
// TODO: Replace all this with proper code to free everything related to the screensaver itself.
XFreeGC(nedsim->dpy, nedsim->gc);
+ XFreePixmap(nedsim->dpy, nedsim->panel);
free(nedsim);
}
static void *
NEDsim_init(Display * dpy, Window win)
{
+ // =========================================================================
+ // Basic Setup
+ // =========================================================================
+
struct NEDsim * nedsim;
- XGCValues gcv;
- XWindowAttributes xgwa;
nedsim = calloc(1, sizeof(*nedsim));
if (!nedsim) {
nedsim->dpy = dpy;
nedsim->win = win;
+ XGCValues gcv;
+ nedsim->gc = XCreateGC(nedsim->dpy, nedsim->win, GCForeground, &gcv);
+
+ XWindowAttributes xgwa;
XGetWindowAttributes(nedsim->dpy, nedsim->win, &xgwa);
nedsim->dpy_width = xgwa.width;
nedsim->dpy_height = xgwa.height;
- // TODO: Explain that this is the delay between each clock cycle of the simulated NED CPU.
+ nedsim->panel = XCreatePixmap(nedsim->dpy, nedsim->win, nedsim->dpy_width, nedsim->dpy_height, xgwa.depth);
+
+ // =========================================================================
+ // Process User Requests
+ // =========================================================================
+
nedsim->delay = get_integer_resource(nedsim->dpy, "delay", "Integer");
nedsim->delay *= 1000; /* Turn milliseconds into microseconds. */
- // Load the program file specified by the user or, if none is specified,
- // randomly select one of the included programs.
+ // If the user did not supply a program for execution, randomly select one
+ // of the included programs.
char * input_file = get_string_resource(nedsim->dpy, "binary", "String");
if (input_file == NULL) {
// TODO: Need to include some default programs and randomly select one to load into RAM.
nedsim->nedstate = init_simulator(input_file);
}
- nedsim->gc = XCreateGC(nedsim->dpy, nedsim->win, GCForeground, &gcv);
-
- // TODO: Do this properly.
- nedsim->color_index = 0;
+ // If the user did not select a color scheme, select one randomly.
+ nedsim->color_index = get_integer_resource(nedsim->dpy, "color", "Integer");
+ if (nedsim->color_index == -1) {
+ nedsim->color_index = random() % sizeof(color_list)/sizeof(color_list[0]);
+ } else if (nedsim->color_index >= sizeof(color_list)/sizeof(color_list[0])) {
+ fprintf(stderr, "WARNING: Color index out of range.\n");
+ nedsim->color_index = 0;
+ }
-// TODO: Save the GIMP reference diagram somewhere, along with notes about the size/spacing, and that each cell is 10 pixels across in the reference image.
+ // =========================================================================
+ // Scale Panel To Screen
+ // =========================================================================
- nedsim->cell_size = nedsim->dpy_width / OVERALL_WIDTH_IN_CELLS ; // make panel as wide as it can be while keeping every cell an integer pixel size.
- // TODO: What is my minimum cell_size? Below that, I should simply paint the window red and print an error in the console. Perform that check here, right after setting cell_size.
- // For now, we'll just make it 10 pixels?
+ // We desire to make the panel as wide as possible while also making the
+ // cell size an integer pixel size.
+ nedsim->cell_size = nedsim->dpy_width / OVERALL_WIDTH_IN_CELLS;
+ // Cell sizes below about 10 pixels result in unreadable fonts. For now,
+ // we'll use that as our cutoff. It also works well with a 1:10 border:cell
+ // ratio.
if (nedsim->cell_size < 10) {
nedsim->suitable_display = False;
return nedsim;
}
- nedsim->origin_x_offset = (nedsim->dpy_width - (nedsim->cell_size * OVERALL_WIDTH_IN_CELLS)) / 2; // center panel horizontally
-
- // Determine how many rows for the stack and heap displays. Make it the largest power of two that fits on the display.
- int available_space_for_data_rows = nedsim->dpy_height - (nedsim->cell_size * (HEADER_HEIGHT_IN_CELLS + FOOTER_HEIGHT_IN_CELLS));
+ // Center the panel horizontally.
+ nedsim->origin_x_offset = (nedsim->dpy_width -
+ (nedsim->cell_size * OVERALL_WIDTH_IN_CELLS)) / 2;
+
+ // The stack and heap displays are variable height. Size them to fit the
+ // display window.
+ int available_space_for_data_rows = nedsim->dpy_height -
+ (nedsim->cell_size * (HEADER_HEIGHT_IN_CELLS + FOOTER_HEIGHT_IN_CELLS));
for (int i = 0; ; i++) {
- if ((nedsim->cell_size * (1 << i)) > available_space_for_data_rows) {
- nedsim->num_data_rows = (1 << --i);
+ if ((nedsim->cell_size * i) > available_space_for_data_rows) {
+ nedsim->num_data_rows = --i;
break;
}
}
+ // Enforce a minimum vertical size, though '4' is arbitrary.
if (nedsim->num_data_rows < 4) {
nedsim->suitable_display = False;
return nedsim;
}
- nedsim->origin_y_offset = (nedsim->dpy_height - (nedsim->cell_size * (HEADER_HEIGHT_IN_CELLS + nedsim->num_data_rows + FOOTER_HEIGHT_IN_CELLS))) / 2; // center panel vertically
+ // Center the panel vertically.
+ nedsim->origin_y_offset = (nedsim->dpy_height -
+ (nedsim->cell_size * (HEADER_HEIGHT_IN_CELLS + nedsim->num_data_rows + FOOTER_HEIGHT_IN_CELLS))) / 2;
// Scale border relative to cell_size in a 1:10 relationship.
nedsim->border_size = nedsim->cell_size / 10;
+ // =========================================================================
+ // Draw Initial Panel
+ // =========================================================================
+
draw_panel(nedsim);
draw_logo(nedsim);
draw_halt(nedsim);
{
struct NEDsim * nedsim = closure;
+ // Update the panel display buffer.
if (nedsim->suitable_display) {
nedsim->nedstate = run_simulator(nedsim->nedstate);
update_display(nedsim);
} else {
set_color(nedsim, &color_list[nedsim->color_index].error_on);
- XFillRectangle(nedsim->dpy, nedsim->win, nedsim->gc, 0, 0, nedsim->dpy_width, nedsim->dpy_height);
+ XFillRectangle(nedsim->dpy, nedsim->panel, nedsim->gc, 0, 0, nedsim->dpy_width, nedsim->dpy_height);
}
+ // Copy panel buffer to display window.
+ XCopyArea(nedsim->dpy, nedsim->panel, nedsim->win, nedsim->gc, 0, 0, nedsim->dpy_width, nedsim->dpy_height, 0, 0);
+
return nedsim->delay;
}
NEDsim_reshape(Display * dpy, Window win, void * closure, unsigned int w, unsigned int h)
{
struct NEDsim * nedsim = closure;
+
+ // Only re-initialize the display if it changed size.
XWindowAttributes xgwa;
XGetWindowAttributes(nedsim->dpy, nedsim->win, &xgwa);
- /* Only restart the simulation if the window changed size. */
if (nedsim->dpy_width != xgwa.width || nedsim->dpy_height != xgwa.height) {
+ // Although we are re-initializing the display, we wish to retain the
+ // in-progress NED simulation. Thus, we retain the NEDstate pointer.
struct NEDstate * original_nedstate = nedsim->nedstate;
nedsim->nedstate = NULL;
NEDsim_free(dpy, win, nedsim);
static const char * NEDsim_defaults[] = {
"*delay: 250",
+ "*color: -1",
0
};
static XrmOptionDescRec NEDsim_options[] = {
{ "-delay", ".delay", XrmoptionSepArg, 0 },
{ "-binary", ".binary", XrmoptionSepArg, 0 },
+ { "-color", ".color", XrmoptionSepArg, 0 },
{ 0, 0, 0, 0 }
};