canvas-axonomgrid.cpp revision c2057a738f9ea8cb7acdeb1feb69cef5b0d4bc56
#define CANVAS_AXONOMGRID_C
/*
* Copyright (C) 2006-2007 Johan Engelen <johan@shouraizou.nl>
*/
/*
* Current limits are: one axis (y-axis) is always vertical. The other two
* axes are bound to a certain range of angles. The z-axis always has an angle
* smaller than 90 degrees (measured from horizontal, 0 degrees being a line extending
* to the right). The x-axis will always have an angle between 0 and 90 degrees.
* When I quickly think about it: all possibilities are probably covered this way. Eg.
* a z-axis with negative angle can be replaced with an x-axis, etc.
*/
/*
* TODO:
* THIS FILE AND THE HEADER FILE NEED CLEANING UP. PLEASE DO NOT HESISTATE TO DO SO.
* For example: the line drawing code should not be here. There _must_ be a function somewhere else that can provide this functionality...
*/
#include "sp-canvas-util.h"
#include "canvas-axonomgrid.h"
#include "util/mathfns.h"
#include "2geom/geom.h"
#include "display-forward.h"
#include <libnr/nr-pixops.h>
#include "canvas-grid.h"
#include "desktop-handles.h"
#include "helper/units.h"
#include "svg/svg-color.h"
#include "xml/node-event-vector.h"
#include "sp-object.h"
#include "sp-namedview.h"
#include "inkscape.h"
#include "desktop.h"
#include "document.h"
#include "prefs-utils.h"
#define SAFE_SETPIXEL //undefine this when it is certain that setpixel is never called with invalid params
enum Dim3 { X=0, Y, Z };
#ifndef M_PI
# define M_PI 3.14159265358979323846
#endif
static double deg_to_rad(double deg) { return deg*M_PI/180.0;}
/**
\brief This function renders a pixel on a particular buffer.
The topleft of the buffer equals
( rect.x0 , rect.y0 ) in screen coordinates
( 0 , 0 ) in setpixel coordinates
The bottomright of the buffer equals
( rect.x1 , rect,y1 ) in screen coordinates
( rect.x1 - rect.x0 , rect.y1 - rect.y0 ) in setpixel coordinates
*/
static void
sp_caxonomgrid_setpixel (SPCanvasBuf *buf, gint x, gint y, guint32 rgba)
{
#ifdef SAFE_SETPIXEL
if ( (x >= buf->rect.x0) && (x < buf->rect.x1) && (y >= buf->rect.y0) && (y < buf->rect.y1) ) {
#endif
guint r, g, b, a;
r = NR_RGBA32_R (rgba);
g = NR_RGBA32_G (rgba);
b = NR_RGBA32_B (rgba);
a = NR_RGBA32_A (rgba);
guchar * p = buf->buf + (y - buf->rect.y0) * buf->buf_rowstride + (x - buf->rect.x0) * 3;
p[0] = NR_COMPOSEN11_1111 (r, a, p[0]);
p[1] = NR_COMPOSEN11_1111 (g, a, p[1]);
p[2] = NR_COMPOSEN11_1111 (b, a, p[2]);
#ifdef SAFE_SETPIXEL
}
#endif
}
/**
\brief This function renders a line on a particular canvas buffer,
using Bresenham's line drawing function.
http://www.cs.unc.edu/~mcmillan/comp136/Lecture6/Lines.html
Coordinates are interpreted as SCREENcoordinates
*/
static void
sp_caxonomgrid_drawline (SPCanvasBuf *buf, gint x0, gint y0, gint x1, gint y1, guint32 rgba)
{
int dy = y1 - y0;
int dx = x1 - x0;
int stepx, stepy;
if (dy < 0) { dy = -dy; stepy = -1; } else { stepy = 1; }
if (dx < 0) { dx = -dx; stepx = -1; } else { stepx = 1; }
dy <<= 1; // dy is now 2*dy
dx <<= 1; // dx is now 2*dx
sp_caxonomgrid_setpixel(buf, x0, y0, rgba);
if (dx > dy) {
int fraction = dy - (dx >> 1); // same as 2*dy - dx
while (x0 != x1) {
if (fraction >= 0) {
y0 += stepy;
fraction -= dx; // same as fraction -= 2*dx
}
x0 += stepx;
fraction += dy; // same as fraction -= 2*dy
sp_caxonomgrid_setpixel(buf, x0, y0, rgba);
}
} else {
int fraction = dx - (dy >> 1);
while (y0 != y1) {
if (fraction >= 0) {
x0 += stepx;
fraction -= dy;
}
y0 += stepy;
fraction += dx;
sp_caxonomgrid_setpixel(buf, x0, y0, rgba);
}
}
}
static void
sp_grid_vline (SPCanvasBuf *buf, gint x, gint ys, gint ye, guint32 rgba)
{
if ((x >= buf->rect.x0) && (x < buf->rect.x1)) {
guint r, g, b, a;
gint y0, y1, y;
guchar *p;
r = NR_RGBA32_R(rgba);
g = NR_RGBA32_G (rgba);
b = NR_RGBA32_B (rgba);
a = NR_RGBA32_A (rgba);
y0 = MAX (buf->rect.y0, ys);
y1 = MIN (buf->rect.y1, ye + 1);
p = buf->buf + (y0 - buf->rect.y0) * buf->buf_rowstride + (x - buf->rect.x0) * 3;
for (y = y0; y < y1; y++) {
p[0] = NR_COMPOSEN11_1111 (r, a, p[0]);
p[1] = NR_COMPOSEN11_1111 (g, a, p[1]);
p[2] = NR_COMPOSEN11_1111 (b, a, p[2]);
p += buf->buf_rowstride;
}
}
}
namespace Inkscape {
/**
* A DIRECT COPY-PASTE FROM DOCUMENT-PROPERTIES.CPP TO QUICKLY GET RESULTS
*
* Helper function that attachs widgets in a 3xn table. The widgets come in an
* array that has two entries per table row. The two entries code for four
* possible cases: (0,0) means insert space in first column; (0, non-0) means
* widget in columns 2-3; (non-0, 0) means label in columns 1-3; and
* (non-0, non-0) means two widgets in columns 2 and 3.
**/
#define SPACE_SIZE_X 15
#define SPACE_SIZE_Y 10
static inline void
attach_all(Gtk::Table &table, Gtk::Widget const *const arr[], unsigned size, int start = 0)
{
for (unsigned i=0, r=start; i<size/sizeof(Gtk::Widget*); i+=2) {
if (arr[i] && arr[i+1]) {
table.attach (const_cast<Gtk::Widget&>(*arr[i]), 1, 2, r, r+1,
Gtk::FILL|Gtk::EXPAND, (Gtk::AttachOptions)0,0,0);
table.attach (const_cast<Gtk::Widget&>(*arr[i+1]), 2, 3, r, r+1,
Gtk::FILL|Gtk::EXPAND, (Gtk::AttachOptions)0,0,0);
} else {
if (arr[i+1]) {
table.attach (const_cast<Gtk::Widget&>(*arr[i+1]), 1, 3, r, r+1,
Gtk::FILL|Gtk::EXPAND, (Gtk::AttachOptions)0,0,0);
} else if (arr[i]) {
Gtk::Label& label = reinterpret_cast<Gtk::Label&> (const_cast<Gtk::Widget&>(*arr[i]));
label.set_alignment (0.0);
table.attach (label, 0, 3, r, r+1,
Gtk::FILL|Gtk::EXPAND, (Gtk::AttachOptions)0,0,0);
} else {
Gtk::HBox *space = manage (new Gtk::HBox);
space->set_size_request (SPACE_SIZE_X, SPACE_SIZE_Y);
table.attach (*space, 0, 1, r, r+1,
(Gtk::AttachOptions)0, (Gtk::AttachOptions)0,0,0);
}
}
++r;
}
}
CanvasAxonomGrid::CanvasAxonomGrid (SPNamedView * nv, Inkscape::XML::Node * in_repr, SPDocument * in_doc)
: CanvasGrid(nv, in_repr, in_doc, GRID_AXONOMETRIC)
{
gridunit = sp_unit_get_by_abbreviation( prefs_get_string_attribute("options.grids.axonom", "units") );
if (!gridunit)
gridunit = &sp_unit_get_by_id(SP_UNIT_PX);
origin[NR::X] = sp_units_get_pixels( prefs_get_double_attribute ("options.grids.axonom", "origin_x", 0.0), *(gridunit) );
origin[NR::Y] = sp_units_get_pixels( prefs_get_double_attribute ("options.grids.axonom", "origin_y", 0.0), *(gridunit) );
color = prefs_get_int_attribute("options.grids.axonom", "color", 0x0000ff20);
empcolor = prefs_get_int_attribute("options.grids.axonom", "empcolor", 0x0000ff40);
empspacing = prefs_get_int_attribute("options.grids.axonom", "empspacing", 5);
lengthy = sp_units_get_pixels( prefs_get_double_attribute ("options.grids.axonom", "spacing_y", 1.0), *(gridunit) );
angle_deg[X] = prefs_get_double_attribute ("options.grids.axonom", "angle_x", 30.0);
angle_deg[Z] = prefs_get_double_attribute ("options.grids.axonom", "angle_z", 30.0);
angle_deg[Y] = 0;
angle_rad[X] = deg_to_rad(angle_deg[X]);
tan_angle[X] = tan(angle_rad[X]);
angle_rad[Z] = deg_to_rad(angle_deg[Z]);
tan_angle[Z] = tan(angle_rad[Z]);
snapper = new CanvasAxonomGridSnapper(this, namedview, 0);
}
CanvasAxonomGrid::~CanvasAxonomGrid ()
{
if (snapper) delete snapper;
}
/* fixme: Collect all these length parsing methods and think common sane API */
static gboolean sp_nv_read_length(gchar const *str, guint base, gdouble *val, SPUnit const **unit)
{
if (!str) {
return FALSE;
}
gchar *u;
gdouble v = g_ascii_strtod(str, &u);
if (!u) {
return FALSE;
}
while (isspace(*u)) {
u += 1;
}
if (!*u) {
/* No unit specified - keep default */
*val = v;
return TRUE;
}
if (base & SP_UNIT_DEVICE) {
if (u[0] && u[1] && !isalnum(u[2]) && !strncmp(u, "px", 2)) {
*unit = &sp_unit_get_by_id(SP_UNIT_PX);
*val = v;
return TRUE;
}
}
if (base & SP_UNIT_ABSOLUTE) {
if (!strncmp(u, "pt", 2)) {
*unit = &sp_unit_get_by_id(SP_UNIT_PT);
} else if (!strncmp(u, "mm", 2)) {
*unit = &sp_unit_get_by_id(SP_UNIT_MM);
} else if (!strncmp(u, "cm", 2)) {
*unit = &sp_unit_get_by_id(SP_UNIT_CM);
} else if (!strncmp(u, "m", 1)) {
*unit = &sp_unit_get_by_id(SP_UNIT_M);
} else if (!strncmp(u, "in", 2)) {
*unit = &sp_unit_get_by_id(SP_UNIT_IN);
} else {
return FALSE;
}
*val = v;
return TRUE;
}
return FALSE;
}
static gboolean sp_nv_read_opacity(gchar const *str, guint32 *color)
{
if (!str) {
return FALSE;
}
gchar *u;
gdouble v = g_ascii_strtod(str, &u);
if (!u) {
return FALSE;
}
v = CLAMP(v, 0.0, 1.0);
*color = (*color & 0xffffff00) | (guint32) floor(v * 255.9999);
return TRUE;
}
void
CanvasAxonomGrid::readRepr()
{
gchar const *value;
if ( (value = repr->attribute("originx")) ) {
sp_nv_read_length(value, SP_UNIT_ABSOLUTE | SP_UNIT_DEVICE, &origin[NR::X], &gridunit);
origin[NR::X] = sp_units_get_pixels(origin[NR::X], *(gridunit));
}
if ( (value = repr->attribute("originy")) ) {
sp_nv_read_length(value, SP_UNIT_ABSOLUTE | SP_UNIT_DEVICE, &origin[NR::Y], &gridunit);
origin[NR::Y] = sp_units_get_pixels(origin[NR::Y], *(gridunit));
}
if ( (value = repr->attribute("spacingy")) ) {
sp_nv_read_length(value, SP_UNIT_ABSOLUTE | SP_UNIT_DEVICE, &lengthy, &gridunit);
lengthy = sp_units_get_pixels(lengthy, *(gridunit));
if (lengthy < 1.0) lengthy = 1.0;
}
if ( (value = repr->attribute("gridanglex")) ) {
angle_deg[X] = g_ascii_strtod(value, NULL);
if (angle_deg[X] < 1.0) angle_deg[X] = 1.0;
if (angle_deg[X] > 89.0) angle_deg[X] = 89.0;
angle_rad[X] = deg_to_rad(angle_deg[X]);
tan_angle[X] = tan(angle_rad[X]);
}
if ( (value = repr->attribute("gridanglez")) ) {
angle_deg[Z] = g_ascii_strtod(value, NULL);
if (angle_deg[Z] < 1.0) angle_deg[Z] = 1.0;
if (angle_deg[Z] > 89.0) angle_deg[Z] = 89.0;
angle_rad[Z] = deg_to_rad(angle_deg[Z]);
tan_angle[Z] = tan(angle_rad[Z]);
}
if ( (value = repr->attribute("color")) ) {
color = (color & 0xff) | sp_svg_read_color(value, color);
}
if ( (value = repr->attribute("empcolor")) ) {
empcolor = (empcolor & 0xff) | sp_svg_read_color(value, empcolor);
}
if ( (value = repr->attribute("opacity")) ) {
sp_nv_read_opacity(value, &color);
}
if ( (value = repr->attribute("empopacity")) ) {
sp_nv_read_opacity(value, &empcolor);
}
if ( (value = repr->attribute("empspacing")) ) {
empspacing = atoi(value);
}
if ( (value = repr->attribute("visible")) ) {
visible = (strcmp(value,"true") == 0);
}
if ( (value = repr->attribute("enabled")) ) {
g_assert(snapper != NULL);
snapper->setEnabled(strcmp(value,"true") == 0);
}
for (GSList *l = canvasitems; l != NULL; l = l->next) {
sp_canvas_item_request_update ( SP_CANVAS_ITEM(l->data) );
}
return;
}
/**
* Called when XML node attribute changed; updates dialog widgets if change was not done by widgets themselves.
*/
void
CanvasAxonomGrid::onReprAttrChanged(Inkscape::XML::Node */*repr*/, gchar const */*key*/, gchar const */*oldval*/, gchar const */*newval*/, bool /*is_interactive*/)
{
readRepr();
if ( ! (_wr.isUpdating()) )
updateWidgets();
}
Gtk::Widget *
CanvasAxonomGrid::newSpecificWidget()
{
Gtk::Table * table = Gtk::manage( new Gtk::Table(1,1) );
table->set_spacings(2);
_wr.setUpdating (true);
Inkscape::UI::Widget::RegisteredUnitMenu *_rumg = new Inkscape::UI::Widget::RegisteredUnitMenu();
Inkscape::UI::Widget::RegisteredScalarUnit *_rsu_ox = new Inkscape::UI::Widget::RegisteredScalarUnit();
Inkscape::UI::Widget::RegisteredScalarUnit *_rsu_oy = new Inkscape::UI::Widget::RegisteredScalarUnit();
Inkscape::UI::Widget::RegisteredScalarUnit *_rsu_sy = new Inkscape::UI::Widget::RegisteredScalarUnit();
Inkscape::UI::Widget::RegisteredScalar *_rsu_ax = Gtk::manage( new Inkscape::UI::Widget::RegisteredScalar(
_("Angle X:"), _("Angle of x-axis"), "gridanglex", _wr, repr, doc ) );
Inkscape::UI::Widget::RegisteredScalar *_rsu_az = Gtk::manage( new Inkscape::UI::Widget::RegisteredScalar(
_("Angle Z:"), _("Angle of z-axis"), "gridanglez", _wr, repr, doc ) );
Inkscape::UI::Widget::RegisteredColorPicker *_rcp_gcol = new Inkscape::UI::Widget::RegisteredColorPicker();
Inkscape::UI::Widget::RegisteredColorPicker *_rcp_gmcol = new Inkscape::UI::Widget::RegisteredColorPicker();
Inkscape::UI::Widget::RegisteredSuffixedInteger *_rsi = new Inkscape::UI::Widget::RegisteredSuffixedInteger();
Inkscape::UI::Widget::ScalarUnit * sutemp = NULL;
_rumg->init (_("Grid _units:"), "units", _wr, repr, doc);
_rsu_ox->init (_("_Origin X:"), _("X coordinate of grid origin"),
"originx", *_rumg, _wr, repr, doc);
sutemp = _rsu_ox->getSU();
sutemp->setDigits(4);
sutemp->setIncrements(0.1, 1.0);
_rsu_oy->init (_("O_rigin Y:"), _("Y coordinate of grid origin"),
"originy", *_rumg, _wr, repr, doc);
sutemp = _rsu_oy->getSU();
sutemp->setDigits(4);
sutemp->setIncrements(0.1, 1.0);
_rsu_sy->init (_("Spacing _Y:"), _("Base length of z-axis"),
"spacingy", *_rumg, _wr, repr, doc);
sutemp = _rsu_sy->getSU();
sutemp->setDigits(4);
sutemp->setIncrements(0.1, 1.0);
_rcp_gcol->init (_("Grid line _color:"), _("Grid line color"),
_("Color of grid lines"), "color", "opacity", _wr, repr, doc);
_rcp_gmcol->init (_("Ma_jor grid line color:"), _("Major grid line color"),
_("Color of the major (highlighted) grid lines"),
"empcolor", "empopacity", _wr, repr, doc);
_rsi->init (_("_Major grid line every:"), _("lines"), "empspacing", _wr, repr, doc);
_wr.setUpdating (false);
Gtk::Widget const *const widget_array[] = {
_rumg->_label, _rumg->_sel,
0, _rsu_ox->getSU(),
0, _rsu_oy->getSU(),
0, _rsu_sy->getSU(),
0, _rsu_ax,
0, _rsu_az,
_rcp_gcol->_label, _rcp_gcol->_cp,
0, 0,
_rcp_gmcol->_label, _rcp_gmcol->_cp,
_rsi->_label, &_rsi->_hbox,
};
attach_all (*table, widget_array, sizeof(widget_array));
if (repr) readRepr();
updateWidgets();
return table;
}
/**
* Update dialog widgets from object's values.
*/
void
CanvasAxonomGrid::updateWidgets()
{
/* if (_wr.isUpdating()) return;
_wr.setUpdating (true);
_rcb_visible.setActive(visible);
if (snapper != NULL) {
_rcb_enabled.setActive(snapper->getEnabled());
}
_rumg.setUnit (gridunit);
gdouble val;
val = origin[NR::X];
val = sp_pixels_get_units (val, *(gridunit));
_rsu_ox.setValue (val);
val = origin[NR::Y];
val = sp_pixels_get_units (val, *(gridunit));
_rsu_oy.setValue (val);
val = lengthy;
double gridy = sp_pixels_get_units (val, *(gridunit));
_rsu_sy.setValue (gridy);
_rsu_ax.setValue(angle_deg[X]);
_rsu_az.setValue(angle_deg[Z]);
_rcp_gcol.setRgba32 (color);
_rcp_gmcol.setRgba32 (empcolor);
_rsi.setValue (empspacing);
_wr.setUpdating (false);
return;
*/
}
void
CanvasAxonomGrid::Update (NR::Matrix const &affine, unsigned int /*flags*/)
{
ow = origin * affine;
sw = NR::Point(fabs(affine[0]),fabs(affine[3]));
for(int dim = 0; dim < 2; dim++) {
gint scaling_factor = empspacing;
if (scaling_factor <= 1)
scaling_factor = 5;
scaled = FALSE;
int watchdog = 0;
while ( (sw[dim] < 8.0) & (watchdog < 100) ) {
scaled = TRUE;
sw[dim] *= scaling_factor;
// First pass, go up to the major line spacing, then
// keep increasing by two.
scaling_factor = 2;
watchdog++;
}
}
spacing_ylines = sw[NR::X] * lengthy /(tan_angle[X] + tan_angle[Z]);
lyw = sw[NR::Y] * lengthy;
lxw_x = (lengthy / tan_angle[X]) * sw[NR::X];
lxw_z = (lengthy / tan_angle[Z]) * sw[NR::X];
if (empspacing == 0) {
scaled = TRUE;
}
}
void
CanvasAxonomGrid::Render (SPCanvasBuf *buf)
{
// gc = gridcoordinates (the coordinates calculated from the grids origin 'grid->ow'.
// sc = screencoordinates ( for example "buf->rect.x0" is in screencoordinates )
// bc = buffer patch coordinates
// tl = topleft ; br = bottomright
NR::Point buf_tl_gc;
NR::Point buf_br_gc;
buf_tl_gc[NR::X] = buf->rect.x0 - ow[NR::X];
buf_tl_gc[NR::Y] = buf->rect.y0 - ow[NR::Y];
buf_br_gc[NR::X] = buf->rect.x1 - ow[NR::X];
buf_br_gc[NR::Y] = buf->rect.y1 - ow[NR::Y];
gdouble x;
gdouble y;
// render the three separate line groups representing the main-axes
// x-axis always goes from topleft to bottomright. (0,0) - (1,1)
gdouble const xintercept_y_bc = (buf_tl_gc[NR::X] * tan_angle[X]) - buf_tl_gc[NR::Y] ;
gdouble const xstart_y_sc = ( xintercept_y_bc - floor(xintercept_y_bc/lyw)*lyw ) + buf->rect.y0;
gint const xlinestart = (gint) Inkscape::round( (xstart_y_sc - buf->rect.x0*tan_angle[X] -ow[NR::Y]) / lyw );
gint xlinenum = xlinestart;
// lines starting on left side.
for (y = xstart_y_sc; y < buf->rect.y1; y += lyw, xlinenum++) {
gint const x0 = buf->rect.x0;
gint const y0 = (gint) Inkscape::round(y);
gint const x1 = x0 + (gint) Inkscape::round( (buf->rect.y1 - y) / tan_angle[X] );
gint const y1 = buf->rect.y1;
if (!scaled && (xlinenum % empspacing) == 0) {
sp_caxonomgrid_drawline (buf, x0, y0, x1, y1, empcolor);
} else {
sp_caxonomgrid_drawline (buf, x0, y0, x1, y1, color);
}
}
// lines starting from top side
gdouble const xstart_x_sc = buf->rect.x0 + (lxw_x - (xstart_y_sc - buf->rect.y0) / tan_angle[X]) ;
xlinenum = xlinestart-1;
for (x = xstart_x_sc; x < buf->rect.x1; x += lxw_x, xlinenum--) {
gint const y0 = buf->rect.y0;
gint const y1 = buf->rect.y1;
gint const x0 = (gint) Inkscape::round(x);
gint const x1 = x0 + (gint) Inkscape::round( (y1 - y0) / tan_angle[X] );
if (!scaled && (xlinenum % empspacing) == 0) {
sp_caxonomgrid_drawline (buf, x0, y0, x1, y1, empcolor);
} else {
sp_caxonomgrid_drawline (buf, x0, y0, x1, y1, color);
}
}
// y-axis lines (vertical)
gdouble const ystart_x_sc = floor (buf_tl_gc[NR::X] / spacing_ylines) * spacing_ylines + ow[NR::X];
gint const ylinestart = (gint) Inkscape::round((ystart_x_sc - ow[NR::X]) / spacing_ylines);
gint ylinenum = ylinestart;
for (x = ystart_x_sc; x < buf->rect.x1; x += spacing_ylines, ylinenum++) {
gint const x0 = (gint) Inkscape::round(x);
if (!scaled && (ylinenum % empspacing) == 0) {
sp_grid_vline (buf, x0, buf->rect.y0, buf->rect.y1 - 1, empcolor);
} else {
sp_grid_vline (buf, x0, buf->rect.y0, buf->rect.y1 - 1, color);
}
}
// z-axis always goes from bottomleft to topright. (0,1) - (1,0)
gdouble const zintercept_y_bc = (buf_tl_gc[NR::X] * -tan_angle[Z]) - buf_tl_gc[NR::Y] ;
gdouble const zstart_y_sc = ( zintercept_y_bc - floor(zintercept_y_bc/lyw)*lyw ) + buf->rect.y0;
gint const zlinestart = (gint) Inkscape::round( (zstart_y_sc + buf->rect.x0*tan_angle[X] - ow[NR::Y]) / lyw );
gint zlinenum = zlinestart;
// lines starting from left side
for (y = zstart_y_sc; y < buf->rect.y1; y += lyw, zlinenum++) {
gint const x0 = buf->rect.x0;
gint const y0 = (gint) Inkscape::round(y);
gint const x1 = x0 + (gint) Inkscape::round( (y - buf->rect.y0 ) / tan_angle[Z] );
gint const y1 = buf->rect.y0;
if (!scaled && (zlinenum % empspacing) == 0) {
sp_caxonomgrid_drawline (buf, x0, y0, x1, y1, empcolor);
} else {
sp_caxonomgrid_drawline (buf, x0, y0, x1, y1, color);
}
}
// draw lines from bottom-up
gdouble const zstart_x_sc = buf->rect.x0 + (y - buf->rect.y1) / tan_angle[Z] ;
for (x = zstart_x_sc; x < buf->rect.x1; x += lxw_z, zlinenum++) {
gint const y0 = buf->rect.y1;
gint const y1 = buf->rect.y0;
gint const x0 = (gint) Inkscape::round(x);
gint const x1 = x0 + (gint) Inkscape::round( (buf->rect.y1 - buf->rect.y0) / tan_angle[Z] );
if (!scaled && (zlinenum % empspacing) == 0) {
sp_caxonomgrid_drawline (buf, x0, y0, x1, y1, empcolor);
} else {
sp_caxonomgrid_drawline (buf, x0, y0, x1, y1, color);
}
}
}
CanvasAxonomGridSnapper::CanvasAxonomGridSnapper(CanvasAxonomGrid *grid, SPNamedView const *nv, NR::Coord const d) : LineSnapper(nv, d)
{
this->grid = grid;
}
LineSnapper::LineList
CanvasAxonomGridSnapper::_getSnapLines(NR::Point const &p) const
{
LineList s;
if ( grid == NULL ) {
return s;
}
/* This is to make sure we snap to only visible grid lines */
double scaled_spacing_h = grid->spacing_ylines; // this is spacing of visible lines if screen pixels
double scaled_spacing_v = grid->lyw; // vertical
// convert screen pixels to px
// FIXME: after we switch to snapping dist in screen pixels, this will be unnecessary
if (SP_ACTIVE_DESKTOP) {
scaled_spacing_h /= SP_ACTIVE_DESKTOP->current_zoom();
scaled_spacing_v /= SP_ACTIVE_DESKTOP->current_zoom();
}
// In an axonometric grid, any point will be surrounded by 6 grid lines:
// - 2 vertical grid lines, one left and one right from the point
// - 2 angled z grid lines, one above and one below the point
// - 2 angled x grid lines, one above and one below the point
// Calculate the x coordinate of the vertical grid lines
NR::Coord x_max = Inkscape::Util::round_to_upper_multiple_plus(p[NR::X], scaled_spacing_h, grid->origin[NR::X]);
NR::Coord x_min = Inkscape::Util::round_to_lower_multiple_plus(p[NR::X], scaled_spacing_h, grid->origin[NR::X]);
// Calculate the y coordinate of the intersection of the angled grid lines with the y-axis
double y_proj_along_z = p[NR::Y] - grid->tan_angle[Z]*(p[NR::X] - grid->origin[NR::X]);
double y_proj_along_x = p[NR::Y] + grid->tan_angle[X]*(p[NR::X] - grid->origin[NR::X]);
double y_proj_along_z_max = Inkscape::Util::round_to_upper_multiple_plus(y_proj_along_z, scaled_spacing_v, grid->origin[NR::Y]);
double y_proj_along_z_min = Inkscape::Util::round_to_lower_multiple_plus(y_proj_along_z, scaled_spacing_v, grid->origin[NR::Y]);
double y_proj_along_x_max = Inkscape::Util::round_to_upper_multiple_plus(y_proj_along_x, scaled_spacing_v, grid->origin[NR::Y]);
double y_proj_along_x_min = Inkscape::Util::round_to_lower_multiple_plus(y_proj_along_x, scaled_spacing_v, grid->origin[NR::Y]);
// Calculate the normal for the angled grid lines
NR::Point norm_x = NR::rot90(NR::Point(1, -grid->tan_angle[X]));
NR::Point norm_z = NR::rot90(NR::Point(1, grid->tan_angle[Z]));
// The four angled grid lines form a parallellogram, enclosing the point
// One of the two vertical grid lines divides this parallellogram in two triangles
// We will now try to find out in which half (i.e. triangle) our point is, and return
// only the three grid lines defining that triangle
// The vertical grid line is at the intersection of two angled grid lines.
// Now go find that intersection!
Geom::Point result;
Geom::IntersectorKind is = line_intersection(norm_x.to_2geom(), norm_x[NR::Y]*y_proj_along_x_max,
norm_z.to_2geom(), norm_z[NR::Y]*y_proj_along_z_max,
result);
// Determine which half of the parallellogram to use
bool use_left_half = true;
bool use_right_half = true;
if (is == Geom::intersects) {
use_left_half = (p[NR::X] - grid->origin[NR::X]) < result[Geom::X];
use_right_half = !use_left_half;
}
//std::cout << "intersection at " << result << " leads to use_left_half = " << use_left_half << " and use_right_half = " << use_right_half << std::endl;
// Return the three grid lines which define the triangle that encloses our point
// If we didn't find an intersection above, all 6 grid lines will be returned
if (use_left_half) {
s.push_back(std::make_pair(norm_z, NR::Point(grid->origin[NR::X], y_proj_along_z_max)));
s.push_back(std::make_pair(norm_x, NR::Point(grid->origin[NR::X], y_proj_along_x_min)));
s.push_back(std::make_pair(component_vectors[NR::X], NR::Point(x_max, 0)));
}
if (use_right_half) {
s.push_back(std::make_pair(norm_z, NR::Point(grid->origin[NR::X], y_proj_along_z_min)));
s.push_back(std::make_pair(norm_x, NR::Point(grid->origin[NR::X], y_proj_along_x_max)));
s.push_back(std::make_pair(component_vectors[NR::X], NR::Point(x_min, 0)));
}
return s;
}
void CanvasAxonomGridSnapper::_addSnappedLine(SnappedConstraints &sc, NR::Point const snapped_point, NR::Coord const snapped_distance, NR::Point const normal_to_line, NR::Point const point_on_line) const
{
SnappedLine dummy = SnappedLine(snapped_point, snapped_distance, getSnapperTolerance(), getSnapperAlwaysSnap(), normal_to_line, point_on_line);
sc.grid_lines.push_back(dummy);
}
}; // namespace Inkscape
/*
Local Variables:
mode:c++
c-file-style:"stroustrup"
c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
indent-tabs-mode:nil
fill-column:99
End:
*/
// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=99 :