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-rw-r--r--third_party/agg23/agg_math_stroke.h272
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diff --git a/third_party/agg23/agg_math_stroke.h b/third_party/agg23/agg_math_stroke.h
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+++ b/third_party/agg23/agg_math_stroke.h
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+
+//----------------------------------------------------------------------------
+// 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 math
+//
+//----------------------------------------------------------------------------
+#ifndef AGG_STROKE_MATH_INCLUDED
+#define AGG_STROKE_MATH_INCLUDED
+#include "agg_math.h"
+#include "agg_vertex_sequence.h"
+namespace agg
+{
+enum line_cap_e {
+ butt_cap,
+ square_cap,
+ round_cap
+};
+enum line_join_e {
+ miter_join = 0,
+ miter_join_revert = 1,
+ miter_join_round = 4,
+ round_join = 2,
+ bevel_join = 3
+};
+enum inner_join_e {
+ inner_bevel,
+ inner_miter,
+ inner_jag,
+ inner_round
+};
+const FX_FLOAT stroke_theta = 1.0f / 1000.0f;
+template<class VertexConsumer>
+void stroke_calc_arc(VertexConsumer& out_vertices,
+ FX_FLOAT x, FX_FLOAT y,
+ FX_FLOAT dx1, FX_FLOAT dy1,
+ FX_FLOAT dx2, FX_FLOAT dy2,
+ FX_FLOAT width,
+ FX_FLOAT approximation_scale)
+{
+ typedef typename VertexConsumer::value_type coord_type;
+ FX_FLOAT a1 = FXSYS_atan2(dy1, dx1);
+ FX_FLOAT a2 = FXSYS_atan2(dy2, dx2);
+ FX_FLOAT da = a1 - a2;
+ bool ccw = da > 0 && da < FX_PI;
+ if(width < 0) {
+ width = -width;
+ }
+ da = FXSYS_acos(FXSYS_Div(width, width + FXSYS_Div(1.0f / 8, approximation_scale))) * 2;
+ out_vertices.add(coord_type(x + dx1, y + dy1));
+ if(!ccw) {
+ if(a1 > a2) {
+ a2 += 2 * FX_PI;
+ }
+ a2 -= da / 4;
+ a1 += da;
+ while(a1 < a2) {
+ out_vertices.add(coord_type(x + FXSYS_Mul(width, FXSYS_cos(a1)),
+ y + FXSYS_Mul(width, FXSYS_sin(a1))));
+ a1 += da;
+ }
+ } else {
+ if(a1 < a2) {
+ a2 -= 2 * FX_PI;
+ }
+ a2 += da / 4;
+ a1 -= da;
+ while(a1 > a2) {
+ out_vertices.add(coord_type(x + FXSYS_Mul(width, FXSYS_cos(a1)),
+ y + FXSYS_Mul(width, FXSYS_sin(a1))));
+ a1 -= da;
+ }
+ }
+ out_vertices.add(coord_type(x + dx2, y + dy2));
+}
+template<class VertexConsumer>
+void stroke_calc_miter(VertexConsumer& out_vertices,
+ const vertex_dist& v0,
+ const vertex_dist& v1,
+ const vertex_dist& v2,
+ FX_FLOAT dx1, FX_FLOAT dy1,
+ FX_FLOAT dx2, FX_FLOAT dy2,
+ FX_FLOAT width,
+ line_join_e line_join,
+ FX_FLOAT miter_limit,
+ FX_FLOAT approximation_scale)
+{
+ typedef typename VertexConsumer::value_type coord_type;
+ FX_FLOAT xi = v1.x;
+ FX_FLOAT yi = v1.y;
+ bool miter_limit_exceeded = true;
+ if(calc_intersection(v0.x + dx1, v0.y - dy1,
+ v1.x + dx1, v1.y - dy1,
+ v1.x + dx2, v1.y - dy2,
+ v2.x + dx2, v2.y - dy2,
+ &xi, &yi)) {
+ FX_FLOAT d1 = calc_distance(v1.x, v1.y, xi, yi);
+ FX_FLOAT lim = FXSYS_Mul(width, miter_limit);
+ if(d1 <= lim) {
+ out_vertices.add(coord_type(xi, yi));
+ miter_limit_exceeded = false;
+ }
+ } else {
+ FX_FLOAT x2 = v1.x + dx1;
+ FX_FLOAT y2 = v1.y - dy1;
+ if((FXSYS_Mul(x2 - v0.x, dy1) - FXSYS_Mul(v0.y - y2, dx1) < 0) !=
+ (FXSYS_Mul(x2 - v2.x, dy1) - FXSYS_Mul(v2.y - y2, dx1) < 0)) {
+ out_vertices.add(coord_type(v1.x + dx1, v1.y - dy1));
+ miter_limit_exceeded = false;
+ }
+ }
+ if(miter_limit_exceeded) {
+ switch(line_join) {
+ case miter_join_revert:
+ out_vertices.add(coord_type(v1.x + dx1, v1.y - dy1));
+ out_vertices.add(coord_type(v1.x + dx2, v1.y - dy2));
+ break;
+ case miter_join_round:
+ stroke_calc_arc(out_vertices,
+ v1.x, v1.y, dx1, -dy1, dx2, -dy2,
+ width, approximation_scale);
+ break;
+ default:
+ out_vertices.add(coord_type(v1.x + dx1 + FXSYS_Mul(dy1, miter_limit),
+ v1.y - dy1 + FXSYS_Mul(dx1, miter_limit)));
+ out_vertices.add(coord_type(v1.x + dx2 - FXSYS_Mul(dy2, miter_limit),
+ v1.y - dy2 - FXSYS_Mul(dx2, miter_limit)));
+ break;
+ }
+ }
+}
+template<class VertexConsumer>
+void stroke_calc_cap(VertexConsumer& out_vertices,
+ const vertex_dist& v0,
+ const vertex_dist& v1,
+ FX_FLOAT len,
+ line_cap_e line_cap,
+ FX_FLOAT width,
+ FX_FLOAT approximation_scale)
+{
+ typedef typename VertexConsumer::value_type coord_type;
+ out_vertices.remove_all();
+ FX_FLOAT dx1 = FXSYS_Div(v1.y - v0.y, len);
+ FX_FLOAT dy1 = FXSYS_Div(v1.x - v0.x, len);
+ FX_FLOAT dx2 = 0;
+ FX_FLOAT dy2 = 0;
+ dx1 = FXSYS_Mul(dx1, width);
+ dy1 = FXSYS_Mul(dy1, width);
+ if(line_cap != round_cap) {
+ if(line_cap == square_cap) {
+ dx2 = dy1;
+ dy2 = dx1;
+ }
+ out_vertices.add(coord_type(v0.x - dx1 - dx2, v0.y + dy1 - dy2));
+ out_vertices.add(coord_type(v0.x + dx1 - dx2, v0.y - dy1 - dy2));
+ } else {
+ FX_FLOAT a1 = FXSYS_atan2(dy1, -dx1);
+ FX_FLOAT a2 = a1 + FX_PI;
+ FX_FLOAT da = FXSYS_acos(FXSYS_Div(width, width +
+ FXSYS_Div(1.0f / 8, approximation_scale))) * 2;
+ out_vertices.add(coord_type(v0.x - dx1, v0.y + dy1));
+ a1 += da;
+ a2 -= da / 4;
+ while(a1 < a2) {
+ out_vertices.add(coord_type(v0.x + FXSYS_Mul(width, FXSYS_cos(a1)),
+ v0.y + FXSYS_Mul(width, FXSYS_sin(a1))));
+ a1 += da;
+ }
+ out_vertices.add(coord_type(v0.x + dx1, v0.y - dy1));
+ }
+}
+template<class VertexConsumer>
+void stroke_calc_join(VertexConsumer& out_vertices,
+ const vertex_dist& v0,
+ const vertex_dist& v1,
+ const vertex_dist& v2,
+ FX_FLOAT len1,
+ FX_FLOAT len2,
+ FX_FLOAT width,
+ line_join_e line_join,
+ inner_join_e inner_join,
+ FX_FLOAT miter_limit,
+ FX_FLOAT inner_miter_limit,
+ FX_FLOAT approximation_scale)
+{
+ typedef typename VertexConsumer::value_type coord_type;
+ FX_FLOAT dx1, dy1, dx2, dy2;
+ dx1 = FXSYS_MulDiv(width, v1.y - v0.y, len1);
+ dy1 = FXSYS_MulDiv(width, v1.x - v0.x, len1);
+ dx2 = FXSYS_MulDiv(width, v2.y - v1.y, len2);
+ dy2 = FXSYS_MulDiv(width, v2.x - v1.x, len2);
+ out_vertices.remove_all();
+ if(calc_point_location(v0.x, v0.y, v1.x, v1.y, v2.x, v2.y) > 0) {
+ switch(inner_join) {
+ default:
+ out_vertices.add(coord_type(v1.x + dx1, v1.y - dy1));
+ out_vertices.add(coord_type(v1.x + dx2, v1.y - dy2));
+ break;
+ case inner_miter:
+ stroke_calc_miter(out_vertices,
+ v0, v1, v2, dx1, dy1, dx2, dy2,
+ width,
+ miter_join_revert,
+ inner_miter_limit,
+ 1.0f);
+ break;
+ case inner_jag:
+ case inner_round: {
+ FX_FLOAT d = (dx1 - dx2) * (dx1 - dx2) + (dy1 - dy2) * (dy1 - dy2);
+ if(d < len1 * len1 && d < len2 * len2) {
+ stroke_calc_miter(out_vertices,
+ v0, v1, v2, dx1, dy1, dx2, dy2,
+ width,
+ miter_join_revert,
+ inner_miter_limit,
+ 1.0f);
+ } else {
+ if(inner_join == inner_jag) {
+ out_vertices.add(coord_type(v1.x + dx1, v1.y - dy1));
+ out_vertices.add(coord_type(v1.x, v1.y ));
+ out_vertices.add(coord_type(v1.x + dx2, v1.y - dy2));
+ } else {
+ out_vertices.add(coord_type(v1.x + dx1, v1.y - dy1));
+ out_vertices.add(coord_type(v1.x, v1.y ));
+ stroke_calc_arc(out_vertices,
+ v1.x, v1.y, dx2, -dy2, dx1, -dy1,
+ width, approximation_scale);
+ out_vertices.add(coord_type(v1.x, v1.y ));
+ out_vertices.add(coord_type(v1.x + dx2, v1.y - dy2));
+ }
+ }
+ }
+ break;
+ }
+ } else {
+ switch(line_join) {
+ case miter_join:
+ case miter_join_revert:
+ case miter_join_round:
+ stroke_calc_miter(out_vertices,
+ v0, v1, v2, dx1, dy1, dx2, dy2,
+ width,
+ line_join,
+ miter_limit,
+ approximation_scale);
+ break;
+ case round_join:
+ stroke_calc_arc(out_vertices,
+ v1.x, v1.y, dx1, -dy1, dx2, -dy2,
+ width, approximation_scale);
+ break;
+ default:
+ out_vertices.add(coord_type(v1.x + dx1, v1.y - dy1));
+ out_vertices.add(coord_type(v1.x + dx2, v1.y - dy2));
+ break;
+ }
+ }
+}
+}
+#endif
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