From 3bdd7b1ed3f93de922f0ef15bd70dc6bfd979566 Mon Sep 17 00:00:00 2001
From: Scott Lahteine <github@thinkyhead.com>
Date: Sat, 3 Feb 2018 19:12:38 -0600
Subject: [PATCH] Reduce trig table down to 6 floats
---
Marlin/G26_Mesh_Validation_Tool.cpp | 106 ++++++++++++----------------
1 file changed, 45 insertions(+), 61 deletions(-)
diff --git a/Marlin/G26_Mesh_Validation_Tool.cpp b/Marlin/G26_Mesh_Validation_Tool.cpp
index b74ec05ac91..88a6252e4f7 100644
--- a/Marlin/G26_Mesh_Validation_Tool.cpp
+++ b/Marlin/G26_Mesh_Validation_Tool.cpp
@@ -48,11 +48,11 @@
#define PRIME_LENGTH 10.0
#define OOZE_AMOUNT 0.3
- #define SIZE_OF_INTERSECTION_CIRCLES 5
- #define SIZE_OF_CROSSHAIRS 3
+ #define INTERSECTION_CIRCLE_RADIUS 5
+ #define CROSSHAIRS_SIZE 3
- #if SIZE_OF_CROSSHAIRS >= SIZE_OF_INTERSECTION_CIRCLES
- #error "SIZE_OF_CROSSHAIRS must be less than SIZE_OF_INTERSECTION_CIRCLES."
+ #if CROSSHAIRS_SIZE >= INTERSECTION_CIRCLE_RADIUS
+ #error "CROSSHAIRS_SIZE must be less than INTERSECTION_CIRCLE_RADIUS."
#endif
#define G26_OK false
@@ -371,7 +371,7 @@
// If the end point of the line is closer to the nozzle, flip the direction,
// moving from the end to the start. On very small lines the optimization isn't worth it.
- if (dist_end < dist_start && (SIZE_OF_INTERSECTION_CIRCLES) < FABS(line_length))
+ if (dist_end < dist_start && (INTERSECTION_CIRCLE_RADIUS) < FABS(line_length))
return print_line_from_here_to_there(ex, ey, ez, sx, sy, sz);
// Decide whether to retract & bump
@@ -411,8 +411,8 @@
// We found two circles that need a horizontal line to connect them
// Print it!
//
- sx = _GET_MESH_X( i ) + (SIZE_OF_INTERSECTION_CIRCLES - (SIZE_OF_CROSSHAIRS)); // right edge
- ex = _GET_MESH_X(i + 1) - (SIZE_OF_INTERSECTION_CIRCLES - (SIZE_OF_CROSSHAIRS)); // left edge
+ sx = _GET_MESH_X( i ) + (INTERSECTION_CIRCLE_RADIUS - (CROSSHAIRS_SIZE)); // right edge
+ ex = _GET_MESH_X(i + 1) - (INTERSECTION_CIRCLE_RADIUS - (CROSSHAIRS_SIZE)); // left edge
sx = constrain(sx, X_MIN_POS + 1, X_MAX_POS - 1);
sy = ey = constrain(_GET_MESH_Y(j), Y_MIN_POS + 1, Y_MAX_POS - 1);
@@ -444,8 +444,8 @@
// We found two circles that need a vertical line to connect them
// Print it!
//
- sy = _GET_MESH_Y( j ) + (SIZE_OF_INTERSECTION_CIRCLES - (SIZE_OF_CROSSHAIRS)); // top edge
- ey = _GET_MESH_Y(j + 1) - (SIZE_OF_INTERSECTION_CIRCLES - (SIZE_OF_CROSSHAIRS)); // bottom edge
+ sy = _GET_MESH_Y( j ) + (INTERSECTION_CIRCLE_RADIUS - (CROSSHAIRS_SIZE)); // top edge
+ ey = _GET_MESH_Y(j + 1) - (INTERSECTION_CIRCLE_RADIUS - (CROSSHAIRS_SIZE)); // bottom edge
sx = ex = constrain(_GET_MESH_X(i), X_MIN_POS + 1, X_MAX_POS - 1);
sy = constrain(sy, Y_MIN_POS + 1, Y_MAX_POS - 1);
@@ -555,9 +555,6 @@
*/
void gcode_G26() {
SERIAL_ECHOLNPGM("G26 command started. Waiting for heater(s).");
- float tmp, start_angle, end_angle;
- int i, xi, yi;
- mesh_index_pair location;
// Don't allow Mesh Validation without homing first,
// or if the parameter parsing did not go OK, abort
@@ -730,17 +727,18 @@
//debug_current_and_destination(PSTR("Starting G26 Mesh Validation Pattern."));
/**
- * Declare and generate a sin() & cos() table to be used during the circle drawing. This will lighten
- * the CPU load and make the arc drawing faster and more smooth
+ * Pre-generate radius offset values at 30 degree intervals to reduce CPU load.
+ * All angles are offset by 15 degrees to allow for a smaller table.
*/
- float sin_table[360 / 15 + 1], cos_table[360 / 15 + 1];
- for (i = 0; i <= 360 / 15; i++) {
- cos_table[i] = SIZE_OF_INTERSECTION_CIRCLES * cos(RADIANS(valid_trig_angle(i * 15.0)));
- sin_table[i] = SIZE_OF_INTERSECTION_CIRCLES * sin(RADIANS(valid_trig_angle(i * 15.0)));
- }
+ #define A_CNT ((360 / 30) / 2)
+ #define _COS(A) (trig_table[((N + A_CNT * 8) % A_CNT)] * (A >= A_CNT ? -1 : 1))
+ #define _SIN(A) (-_COS((A + A_CNT / 2) % (A_CNT * 2)))
+ float trig_table[A_CNT];
+ for (uint8_t i = 0; i < A_CNT; i++)
+ trig_table[i] = INTERSECTION_CIRCLE_RADIUS * cos(RADIANS(i * 30 + 15));
do {
- location = g26_continue_with_closest
+ const mesh_index_pair location = g26_continue_with_closest
? find_closest_circle_to_print(current_position[X_AXIS], current_position[Y_AXIS])
: find_closest_circle_to_print(g26_x_pos, g26_y_pos); // Find the closest Mesh Intersection to where we are now.
@@ -749,12 +747,29 @@
circle_y = _GET_MESH_Y(location.y_index);
// If this mesh location is outside the printable_radius, skip it.
-
if (!position_is_reachable(circle_x, circle_y)) continue;
- xi = location.x_index; // Just to shrink the next few lines and make them easier to understand
- yi = location.y_index;
-
+ // Determine where to start and end the circle,
+ // which is always drawn counter-clockwise.
+ const uint8_t xi = location.x_index, yi = location.y_index;
+ const bool f = yi == 0, r = xi == GRID_MAX_POINTS_X - 1, b = yi == GRID_MAX_POINTS_Y - 1;
+ int8_t start_ind = -2, end_ind = 10; // Assume a full circle (from 4:30 to 4:30)
+ if (xi == 0) { // Left edge? Just right half.
+ start_ind = f ? 0 : -3; // 05:30 (02:30 for front-left)
+ end_ind = b ? -1 : 2; // 12:30 (03:30 for back-left)
+ }
+ else if (r) { // Right edge? Just left half.
+ start_ind = f ? 5 : 3; // 11:30 (09:30 for front-right)
+ end_ind = b ? 6 : 8; // 06:30 (08:30 for back-right)
+ }
+ else if (f) { // Front edge? Just back half.
+ start_ind = 0; // 02:30
+ end_ind = 5; // 09:30
+ }
+ else if (b) { // Back edge? Just front half.
+ start_ind = 6; // 08:30
+ end_ind = 11; // 03:30
+ }
if (g26_debug_flag) {
SERIAL_ECHOPAIR(" Doing circle at: (xi=", xi);
SERIAL_ECHOPAIR(", yi=", yi);
@@ -762,48 +777,17 @@
SERIAL_EOL();
}
- // start and end the circle at an 45 degree angle to avoid lines crossing start-/end-points
- start_angle = -45.0; // assume it is going to be a full circle
- end_angle = 315.0;
- if (xi == 0) { // Check for bottom edge
- start_angle = -75.0;
- end_angle = 75.0;
- if (yi == 0) // it is an edge, check for the two left corners
- start_angle = 15.0;
- else if (yi == GRID_MAX_POINTS_Y - 1)
- end_angle = -15.0;
- }
- else if (xi == GRID_MAX_POINTS_X - 1) { // Check for top edge
- start_angle = 105.0;
- end_angle = 255.0;
- if (yi == 0) // it is an edge, check for the two right corners
- end_angle = 165.0;
- else if (yi == GRID_MAX_POINTS_Y - 1)
- start_angle = 195.0;
- }
- else if (yi == 0) {
- start_angle = 15.0; // only do the top side of the circle
- end_angle = 165.0;
- }
- else if (yi == GRID_MAX_POINTS_Y - 1) {
- start_angle = 195.0; // only do the bottom side of the circle
- end_angle = 345.0;
- }
-
- for (tmp = start_angle; tmp < end_angle - 0.1; tmp += 30.0) {
+ for (int8_t ind = start_ind; ind < end_ind; ind++) {
#if ENABLED(NEWPANEL)
- if (user_canceled()) goto LEAVE; // Check if the user wants to stop the Mesh Validation
+ if (user_canceled()) goto LEAVE; // Check if the user wants to stop the Mesh Validation
#endif
- int tmp_div_15 = tmp / 15.0;
- while (tmp_div_15 < 0) tmp_div_15 += 360 / 15;
- while (tmp_div_15 >= 360 / 15) tmp_div_15 -= 360 / 15;
+ float rx = circle_x + _COS(ind), // For speed, these are now a lookup table entry
+ ry = circle_y + _SIN(ind),
+ xe = circle_x + _COS(ind + 1),
+ ye = circle_y + _SIN(ind + 1);
- float rx = circle_x + cos_table[tmp_div_15], // for speed, these are now a lookup table entry
- ry = circle_y + sin_table[tmp_div_15],
- xe = circle_x + cos_table[tmp_div_15 + 1],
- ye = circle_y + sin_table[tmp_div_15 + 1];
#if IS_KINEMATIC
// Check to make sure this segment is entirely on the bed, skip if not.
if (!position_is_reachable(rx, ry) || !position_is_reachable(xe, ye)) continue;