[game] resolve collisions when following perpendicularly

ghthor · Feb 21, 2015 · 3ad73e2 · 3ad73e2
1 parent 40a807e
commit 3ad73e2
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Showing 2 changed files with 58 additions and 0 deletions.
diff --git a/game/sim.go b/game/sim.go
@@ -139,6 +139,17 @@ func (phase narrowPhase) resolveActorActorCollision(a, b *actor) {
 		pathCollision := coord.NewPathCollision(*a.pathAction, *b.pathAction)
 
 		switch pathCollision.Type() {
+		case coord.CT_A_INTO_B_FROM_SIDE:
+			if *a.pathAction == pathCollision.B {
+				a, b = b, a
+			}
+
+			if a.pathAction.End() >= b.pathAction.End() {
+				return
+			}
+
+			fallthrough
+
 		case coord.CT_A_INTO_B:
 			if *a.pathAction == pathCollision.A {
 				a.undoLastMoveAction()

diff --git a/game/sim_test.go b/game/sim_test.go
@@ -174,8 +174,55 @@ func DescribeCollision(c gospec.Context) {
 					})
 				}
 
+				c.Specify("in perpendicular directions", func() {
+					testCases := []spec_2moving{{
+						spec: "allows the leader to move",
+						paths: []coord.PathAction{
+							pa(0, 10, cell(0, 0), cell(1, 0)),
+							pa(0, 9, cell(0, -1), cell(0, 0)),
+						},
+						expectations: func(testCase spec_2moving, index actorIndex, c gospec.Context) {
+							c.Assume(testCase.paths[0].Direction(), Equals, coord.East)
+							c.Assume(testCase.paths[1].Direction(), Equals, coord.North)
+							c.Expect(*index[0].pathAction, Equals, testCase.paths[0])
+							c.Expect(index[1].pathAction, IsNil)
+						},
+					}, {
+						spec: "allows both to move",
+						paths: []coord.PathAction{
+							pa(0, 10, cell(0, 0), cell(1, 0)),
+							pa(0, 10, cell(0, -1), cell(0, 0)),
+						},
+						expectations: func(testCase spec_2moving, index actorIndex, c gospec.Context) {
+							c.Assume(testCase.paths[0].Direction(), Equals, coord.East)
+							c.Assume(testCase.paths[1].Direction(), Equals, coord.North)
+							c.Expect(*index[0].pathAction, Equals, testCase.paths[0])
+							c.Expect(*index[1].pathAction, Equals, testCase.paths[1])
+						},
+					}, {
+						spec: "allows both to move",
+						paths: []coord.PathAction{
+							pa(0, 10, cell(0, 0), cell(1, 0)),
+							pa(0, 11, cell(0, -1), cell(0, 0)),
+						},
+						expectations: func(testCase spec_2moving, index actorIndex, c gospec.Context) {
+							c.Assume(testCase.paths[0].Direction(), Equals, coord.East)
+							c.Assume(testCase.paths[1].Direction(), Equals, coord.North)
+							c.Expect(*index[0].pathAction, Equals, testCase.paths[0])
+							c.Expect(*index[1].pathAction, Equals, testCase.paths[1])
+						},
+					}}
+
+					for _, testCase := range testCases {
+						c.Specify(testCase.spec, func() {
+							testCase.runSpec(c)
+						})
+					}
+				})
+
 				c.Specify("and contesting the same location", func() {
 					c.Specify("from the side", func() {
+
 						testCases := []spec_2moving{{
 							spec: "moving east loses to moving north",
 							paths: []coord.PathAction{