beter join handling, dot = -1 still problematic

diff --git a/src/vkvg_context_internal.c b/src/vkvg_context_internal.c
index ddc120e091a87cb92108e0625fa632ecb09ca556..b8419e857ec0894fd8d43f69aab290e8c792ab33 100644 (file)
--- a/src/vkvg_context_internal.c
+++ b/src/vkvg_context_internal.c
@@ -193,8 +193,11 @@ void _resetMinMax (VkvgContext ctx) {
 void _add_point (VkvgContext ctx, float x, float y){
        if (_check_point_array(ctx))
                return;
+       vec2 v = {x,y};
+       /*if (!_current_path_is_empty(ctx) && vec2_length(vec2_sub(ctx->points[ctx->pointCount-1], v))<1.f)
+               return;*/
 
-       ctx->points[ctx->pointCount] = (vec2){x,y};
+       ctx->points[ctx->pointCount] = v;
        ctx->pointCount++;//total point count of pathes, (for array bounds check)
        ctx->pathes[ctx->pathPtr]++;//total point count in path
        if (ctx->segmentPtr > 0)
@@ -796,7 +799,7 @@ bool _build_vb_step (vkvg_context* ctx, float hw, stroke_context_t* str, bool is
 
        //limit bisectrice length
        float rlh = lh;
-       if (dot<0.f)
+       if (dot < 0.f)
                rlh = fminf (rlh, fminf (length_v0, length_v1));
        //---
 
@@ -804,63 +807,82 @@ bool _build_vb_step (vkvg_context* ctx, float hw, stroke_context_t* str, bool is
 
        VKVG_IBO_INDEX_TYPE idx = (VKVG_IBO_INDEX_TYPE)(ctx->vertCount - ctx->curVertOffset);
 
-       vec2 rlh_inside_pos;
-
-       if (!isCurve && (rlh < lh || ctx->lineJoin != VKVG_LINE_JOIN_MITER)) {
+       vec2 rlh_inside_pos, rlh_outside_pos;
+       if (rlh < lh) {
                vec2 vnPerp;
                if (length_v0 < length_v1)
                        vnPerp = vec2_perp (v1n);
                else
                        vnPerp = vec2_perp (v0n);
                vec2 vHwPerp = vec2_mult_s(vnPerp, hw);
+
                double lbc = cosf(halfAlpha) * rlh;
-               if (det < 0.f)
-                       rlh_inside_pos = vec2_add (vec2_add (vec2_mult_s(vnPerp, -lbc), vec2_add(p0, bisec)), vHwPerp);
-               else
-                       rlh_inside_pos = vec2_sub (vec2_add (vec2_mult_s(vnPerp, lbc), vec2_sub(p0, bisec)), vHwPerp);
+               if (det < 0.f) {
+                       rlh_inside_pos  = vec2_add (vec2_add (vec2_mult_s(vnPerp, -lbc), vec2_add(p0, bisec)), vHwPerp);
+                       rlh_outside_pos = vec2_sub (p0, vec2_mult_s (bisec_n_perp, lh));
+               } else {
+                       rlh_inside_pos  = vec2_sub (vec2_add (vec2_mult_s(vnPerp, lbc), vec2_sub(p0, bisec)), vHwPerp);
+                       rlh_outside_pos = vec2_add (p0, vec2_mult_s (bisec_n_perp, lh));
+               }
+       } else {
+               if (det < 0.0) {
+                       rlh_inside_pos  = vec2_add (p0, bisec);
+                       rlh_outside_pos = vec2_sub (p0, bisec);
+               } else {
+                       rlh_inside_pos  = vec2_sub (p0, bisec);
+                       rlh_outside_pos = vec2_add (p0, bisec);
+               }
        }
 
+
        if (ctx->lineJoin == VKVG_LINE_JOIN_MITER || isCurve){
-               if (!isCurve && dot < 0.f && rlh < lh) {
+               if (dot < -0.95f && rlh < lh) {
                        double x = (lh - rlh) * cosf (halfAlpha);
                        vec2 bisecPerp = vec2_mult_s (bisec_n, x);
-                       vec2 p = vec2_add(p0, bisec);
-                       if (det > 0) {
-                               v.pos = vec2_sub(p, bisecPerp);
-                               _add_vertex(ctx, v);
-
+                       if (det < 0) {
                                v.pos = rlh_inside_pos;
                                _add_vertex(ctx, v);
 
+                               vec2 p = vec2_sub(p0, bisec);
+
+                               v.pos = vec2_sub(p, bisecPerp);
+                               _add_vertex(ctx, v);
                                v.pos = vec2_add(p, bisecPerp);
                                _add_vertex(ctx, v);
 
                                _add_triangle_indices(ctx, idx, idx+2, idx+1);
-                               _add_triangle_indices(ctx, idx+2, idx+3, idx+1);
-                               _add_triangle_indices(ctx, idx+1, idx+3, idx+4);
-                               return false;
+                               _add_triangle_indices(ctx, idx+2, idx+4, idx);
+                               _add_triangle_indices(ctx, idx, idx+3, idx+4);
+                               return true;
                        } else {
-                               v.pos = v.pos = rlh_inside_pos;
+                               vec2 p = vec2_add(p0, bisec);
+                               v.pos = vec2_sub(p, bisecPerp);
                                _add_vertex(ctx, v);
 
-                               p = vec2_sub(p0, bisec);
-
-                               v.pos = vec2_sub(p, bisecPerp);
+                               v.pos = rlh_inside_pos;
                                _add_vertex(ctx, v);
+
                                v.pos = vec2_add(p, bisecPerp);
                                _add_vertex(ctx, v);
 
                                _add_triangle_indices(ctx, idx, idx+2, idx+1);
-                               _add_triangle_indices(ctx, idx+2, idx+4, idx);
-                               _add_triangle_indices(ctx, idx, idx+3, idx+4);
-                               return true;
+                               _add_triangle_indices(ctx, idx+2, idx+3, idx+1);
+                               _add_triangle_indices(ctx, idx+1, idx+3, idx+4);
+                               return false;
                        }
 
                } else {
-                       v.pos = vec2_add(p0, bisec);
-                       _add_vertex(ctx, v);
-                       v.pos = vec2_sub(p0, bisec);
-                       _add_vertex(ctx, v);
+                       if (det < 0) {
+                               v.pos = rlh_inside_pos;
+                               _add_vertex(ctx, v);
+                               v.pos = rlh_outside_pos;
+                               _add_vertex(ctx, v);
+                       } else {
+                               v.pos = rlh_outside_pos;
+                               _add_vertex(ctx, v);
+                               v.pos = rlh_inside_pos;
+                               _add_vertex(ctx, v);
+                       }
 
                        _add_tri_indices_for_rect(ctx, idx);
                        return false;