xref: /external/pdfium/core/src/fxge/agg/agg23/fx_agg_vcgen_stroke.cpp

//----------------------------------------------------------------------------
// XYQ: 2006-01-22 Copied from AGG project.
// TODO: This file uses intensive floating point operations, so it's NOT suitable
// for platforms like Symbian OS. We need to change to FIX format.
//----------------------------------------------------------------------------
//----------------------------------------------------------------------------
// Anti-Grain Geometry - Version 2.3
// Copyright (C) 2002-2005 Maxim Shemanarev (http://www.antigrain.com)
//
// Permission to copy, use, modify, sell and distribute this software
// is granted provided this copyright notice appears in all copies.
// This software is provided "as is" without express or implied
// warranty, and with no claim as to its suitability for any purpose.
//
//----------------------------------------------------------------------------
// Contact: mcseem@antigrain.com
//          mcseemagg@yahoo.com
//          http://www.antigrain.com
//----------------------------------------------------------------------------
//
// Stroke generator
//
//----------------------------------------------------------------------------
#include "../../../../include/fxcrt/fx_basic.h"
#include "agg_vcgen_stroke.h"
namespace agg
{

vcgen_stroke::vcgen_stroke() :
    m_src_vertices(),
    m_out_vertices(),
    m_width(0.5f),
    m_miter_limit(4 * 1.0f),
    m_inner_miter_limit(1.0f + 1.0f / 100),
    m_approx_scale(1.0f),
    m_line_cap(butt_cap),
    m_line_join(miter_join),
    m_inner_join(inner_miter),
    m_closed(0),
    m_status(initial),
    m_src_vertex(0),
    m_out_vertex(0)
{
}
void vcgen_stroke::remove_all()
{
    m_src_vertices.remove_all();
    m_closed = 0;
    m_status = initial;
}
void vcgen_stroke::add_vertex(FX_FLOAT x, FX_FLOAT y, unsigned cmd)
{
    m_status = initial;
    if(is_move_to(cmd)) {
        m_src_vertices.modify_last(vertex_dist_cmd(x, y, cmd));
    } else {
        if(is_vertex(cmd)) {
            m_src_vertices.add(vertex_dist_cmd(x, y, cmd));
        } else {
            m_closed = get_close_flag(cmd);
        }
    }
}
static inline void calc_butt_cap(FX_FLOAT* cap,
                                 const vertex_dist& v0,
                                 const vertex_dist& v1,
                                 FX_FLOAT len,
                                 FX_FLOAT width)
{
    FX_FLOAT dx = FXSYS_MulDiv(v1.y - v0.y, width, len);
    FX_FLOAT dy = FXSYS_MulDiv(v1.x - v0.x, width, len);
    cap[0] = v0.x - dx;
    cap[1] = v0.y + dy;
    cap[2] = v0.x + dx;
    cap[3] = v0.y - dy;
}
void vcgen_stroke::rewind(unsigned)
{
    if(m_status == initial) {
        m_src_vertices.close(m_closed != 0);
        if(m_src_vertices.size() < 3) {
            m_closed = 0;
        }
    }
    m_status = ready;
    m_src_vertex = 0;
    m_out_vertex = 0;
}
unsigned vcgen_stroke::vertex(FX_FLOAT* x, FX_FLOAT* y)
{
    unsigned cmd = path_cmd_line_to;
    line_join_e curj;
    while(!is_stop(cmd)) {
        switch(m_status) {
            case initial:
                rewind(0);
            case ready:
                if(m_src_vertices.size() < 2 + unsigned(m_closed != 0)) {
                    cmd = path_cmd_stop;
                    break;
                }
                m_status = m_closed ? outline1 : cap1;
                cmd = path_cmd_move_to;
                m_src_vertex = 0;
                m_out_vertex = 0;
                break;
            case cap1:
                stroke_calc_cap(m_out_vertices,
                                m_src_vertices[0],
                                m_src_vertices[1],
                                m_src_vertices[0].dist,
                                m_line_cap,
                                m_width,
                                m_approx_scale);
                m_src_vertex = 1;
                m_prev_status = outline1;
                m_status = out_vertices;
                m_out_vertex = 0;
                break;
            case cap2:
                stroke_calc_cap(m_out_vertices,
                                m_src_vertices[m_src_vertices.size() - 1],
                                m_src_vertices[m_src_vertices.size() - 2],
                                m_src_vertices[m_src_vertices.size() - 2].dist,
                                m_line_cap,
                                m_width,
                                m_approx_scale);
                m_prev_status = outline2;
                m_status = out_vertices;
                m_out_vertex = 0;
                break;
            case outline1:
                if(m_closed) {
                    if(m_src_vertex >= m_src_vertices.size()) {
                        m_prev_status = close_first;
                        m_status = end_poly1;
                        break;
                    }
                } else {
                    if(m_src_vertex >= m_src_vertices.size() - 1) {
                        m_status = cap2;
                        break;
                    }
                }
                curj = m_src_vertices[m_src_vertex].cmd & path_flags_jr ? miter_join_round : m_line_join;
                stroke_calc_join(m_out_vertices,
                                 m_src_vertices.prev(m_src_vertex),
                                 m_src_vertices.curr(m_src_vertex),
                                 m_src_vertices.next(m_src_vertex),
                                 m_src_vertices.prev(m_src_vertex).dist,
                                 m_src_vertices.curr(m_src_vertex).dist,
                                 m_width,
                                 curj,
                                 m_inner_join,
                                 m_miter_limit,
                                 m_inner_miter_limit,
                                 m_approx_scale);
                ++m_src_vertex;
                m_prev_status = m_status;
                m_status = out_vertices;
                m_out_vertex = 0;
                break;
            case close_first:
                m_status = outline2;
                cmd = path_cmd_move_to;
            case outline2:
                if(m_src_vertex <= unsigned(m_closed == 0)) {
                    m_status = end_poly2;
                    m_prev_status = stop;
                    break;
                }
                --m_src_vertex;
                curj = m_src_vertices[m_src_vertex].cmd & path_flags_jr ? miter_join_round : m_line_join;
                stroke_calc_join(m_out_vertices,
                                 m_src_vertices.next(m_src_vertex),
                                 m_src_vertices.curr(m_src_vertex),
                                 m_src_vertices.prev(m_src_vertex),
                                 m_src_vertices.curr(m_src_vertex).dist,
                                 m_src_vertices.prev(m_src_vertex).dist,
                                 m_width,
                                 curj,
                                 m_inner_join,
                                 m_miter_limit,
                                 m_inner_miter_limit,
                                 m_approx_scale);
                m_prev_status = m_status;
                m_status = out_vertices;
                m_out_vertex = 0;
                break;
            case out_vertices:
                if(m_out_vertex >= m_out_vertices.size()) {
                    m_status = m_prev_status;
                } else {
                    const point_type& c = m_out_vertices[m_out_vertex++];
                    *x = c.x;
                    *y = c.y;
                    return cmd;
                }
                break;
            case end_poly1:
                m_status = m_prev_status;
                return path_cmd_end_poly | path_flags_close | path_flags_ccw;
            case end_poly2:
                m_status = m_prev_status;
                return path_cmd_end_poly | path_flags_close | path_flags_cw;
            case stop:
                cmd = path_cmd_stop;
                break;
        }
    }
    return cmd;
}
}