From: Jean-Philippe Bruyère <jp_bruyere@hotmail.com>
Date: Mon, 29 Nov 2021 05:07:16 +0000 (+0100)
Subject: dynamic distanceTolerance in _recursive_bezier
X-Git-Tag: v0.2.0~49
X-Git-Url: https://git.osiis.dedyn.io/?a=commitdiff_plain;h=bd4255a6a92d251d81fc672ee6d5468477753f0e;p=jp%2Fvkvg.git

dynamic distanceTolerance in _recursive_bezier
---

diff --git a/src/vkvg_context.c b/src/vkvg_context.c
index 5f912e6..c53369c 100644
--- a/src/vkvg_context.c
+++ b/src/vkvg_context.c
@@ -496,7 +496,12 @@ void vkvg_curve_to (VkvgContext ctx, float x1, float y1, float x2, float y2, flo
 
 	vec2 cp = _get_current_position(ctx);
 
-	_recursive_bezier (ctx, cp.x, cp.y, x1, y1, x2, y2, x3, y3, 0);
+	//compute dyn distanceTolerance depending on current transform
+	float dx = 1, dy = 1;
+	vkvg_matrix_transform_distance (&ctx->pushConsts.mat, &dx, &dy);
+	float distanceTolerance = 0.02f / fmaxf(dx,dy);
+
+	_recursive_bezier (ctx, distanceTolerance, cp.x, cp.y, x1, y1, x2, y2, x3, y3, 0);
 	/*cp.x = x3;
 	cp.y = y3;
 	if (!vec2_equ(ctx->points[ctx->pointCount-1],cp))*/
diff --git a/src/vkvg_context_internal.c b/src/vkvg_context_internal.c
index d5be84a..a1a634c 100644
--- a/src/vkvg_context_internal.c
+++ b/src/vkvg_context_internal.c
@@ -880,14 +880,13 @@ void _free_ctx_save (vkvg_context_save_t* sav){
 
 #define M_APPROXIMATION_SCALE	1.0
 #define M_ANGLE_TOLERANCE		0.01
-#define M_DISTANCE_TOLERANCE	1.0
 #define M_CUSP_LIMIT			0.01
-#define CURVE_RECURSION_LIMIT	10
+#define CURVE_RECURSION_LIMIT	100
 #define CURVE_COLLINEARITY_EPSILON 1.7
 #define CURVE_ANGLE_TOLERANCE_EPSILON 0.001
 //no floating point arithmetic operation allowed in macro.
 #pragma warning(disable:4127)
-void _recursive_bezier (VkvgContext ctx,
+void _recursive_bezier (VkvgContext ctx, float distanceTolerance,
 						float x1, float y1, float x2, float y2,
 						float x3, float y3, float x4, float y4,
 						unsigned level) {
@@ -927,7 +926,7 @@ void _recursive_bezier (VkvgContext ctx,
 		{
 			// Regular care
 			//-----------------
-			if((d2 + d3)*(d2 + d3) <= (dx*dx + dy*dy) * (float)M_DISTANCE_TOLERANCE)
+			if((d2 + d3)*(d2 + d3) <= (dx*dx + dy*dy) * distanceTolerance)
 			{
 				// If the curvature doesn't exceed the distance_tolerance value
 				// we tend to finish subdivisions.
@@ -973,7 +972,7 @@ void _recursive_bezier (VkvgContext ctx,
 			{
 				// p1,p3,p4 are collinear, p2 is considerable
 				//----------------------
-				if(d2 * d2 <= (float)M_DISTANCE_TOLERANCE * (dx*dx + dy*dy))
+				if(d2 * d2 <= distanceTolerance * (dx*dx + dy*dy))
 				{
 					if(M_ANGLE_TOLERANCE < CURVE_ANGLE_TOLERANCE_EPSILON)
 					{
@@ -1005,7 +1004,7 @@ void _recursive_bezier (VkvgContext ctx,
 			} else if(d3 > CURVE_COLLINEARITY_EPSILON) {
 				// p1,p2,p4 are collinear, p3 is considerable
 				//----------------------
-				if(d3 * d3 <= (float)M_DISTANCE_TOLERANCE * (dx*dx + dy*dy))
+				if(d3 * d3 <= distanceTolerance* (dx*dx + dy*dy))
 				{
 					if(M_ANGLE_TOLERANCE < CURVE_ANGLE_TOLERANCE_EPSILON)
 					{
@@ -1041,7 +1040,7 @@ void _recursive_bezier (VkvgContext ctx,
 				//-----------------
 				dx = x1234 - (x1 + x4) / 2;
 				dy = y1234 - (y1 + y4) / 2;
-				if(dx*dx + dy*dy <= (float)M_DISTANCE_TOLERANCE)
+				if(dx*dx + dy*dy <= distanceTolerance)
 				{
 					_add_point (ctx, x1234, y1234);
 					return;
@@ -1052,8 +1051,8 @@ void _recursive_bezier (VkvgContext ctx,
 
 	// Continue subdivision
 	//----------------------
-	_recursive_bezier (ctx, x1, y1, x12, y12, x123, y123, x1234, y1234, level + 1);
-	_recursive_bezier (ctx, x1234, y1234, x234, y234, x34, y34, x4, y4, level + 1);
+	_recursive_bezier (ctx, distanceTolerance, x1, y1, x12, y12, x123, y123, x1234, y1234, level + 1);
+	_recursive_bezier (ctx, distanceTolerance,x1234, y1234, x234, y234, x34, y34, x4, y4, level + 1);
 }
 #pragma warning(default:4127)
 
diff --git a/src/vkvg_context_internal.h b/src/vkvg_context_internal.h
index 7013690..9c6f962 100644
--- a/src/vkvg_context_internal.h
+++ b/src/vkvg_context_internal.h
@@ -254,7 +254,7 @@ static inline float vec2_zcross (vec2 v1, vec2 v2){
 static inline float ecp_zcross (ear_clip_point* p0, ear_clip_point* p1, ear_clip_point* p2){
 	return vec2_zcross (vec2_sub (p1->pos, p0->pos), vec2_sub (p2->pos, p0->pos));
 }
-void _recursive_bezier(VkvgContext ctx,
+void _recursive_bezier(VkvgContext ctx, float distanceTolerance,
 					   float x1, float y1, float x2, float y2,
 					   float x3, float y3, float x4, float y4,
 					   unsigned level);