[Scummvm-git-logs] scummvm master -> f2195d8dbfd17ae50e094710cdc2207387d5415c

[aquadran]

This automated email contains information about 1 new commit which have been
pushed to the 'scummvm' repo located at https://github.com/scummvm/scummvm .

Summary:
f2195d8dbf MATH: Make implementation of Segment2d more robust


Commit: f2195d8dbfd17ae50e094710cdc2207387d5415c
    https://github.com/scummvm/scummvm/commit/f2195d8dbfd17ae50e094710cdc2207387d5415c
Author: Christian Krause (chkr at plauener.de)
Date: 2020-12-08T19:09:08+01:00

Commit Message:
MATH: Make implementation of Segment2d more robust

- prevent division by zero

Changed paths:
    math/line2d.cpp
    math/utils.h


diff --git a/math/line2d.cpp b/math/line2d.cpp
index 5a269ebddd..9a89485b79 100644
--- a/math/line2d.cpp
+++ b/math/line2d.cpp
@@ -169,14 +169,14 @@ bool Segment2d::intersectsSegment(const Segment2d &other, Vector2d *pos) {
 	float nume_b = ((_end.getX() - _begin.getX()) * (other._begin.getY() - _begin.getY())) -
 	((_end.getY() - _begin.getY()) * (other._begin.getX() - _begin.getX()));
 
-	if (denom == 0.0f) {
+	if (denom == 0.0f || d == 0.0f ) {
 		return false;
 	}
 
 	float ua = nume_a / denom;
 	float ub = nume_b / d;
 
-	if (ua < 0 || ua > 1 || ub < 0 || ub > 1) {
+	if (ua < 0.0f || ua > 1.0f || ub < 0.0f || ub > 1.0f) {
 		return false;
 	}
 
diff --git a/math/utils.h b/math/utils.h
index 2d08ee03d6..00060c02a3 100644
--- a/math/utils.h
+++ b/math/utils.h
@@ -27,6 +27,15 @@
 
 namespace Math {
 
+/* Math::epsilon is a constant with a small value which is used for comparing
+ * floating point numbers.
+ *
+ * The value is based on the previous hard-coded numbers in
+ * Line2d.cpp. Smaller numbers could be used unless they are
+ * smaller than the float granularity.
+ */
+static const float epsilon = 0.0001f;
+
 inline float square(float x) {
 	return x * x;
 }