Add rotation based on TMX flipping flag (#780)

* add rotation based on TMX flip

* add rotation to example

common/level.go

@@ -281,4 +281,6 @@ type Tile struct {
 	Image     *Texture
 	Drawables []Drawable
 	Animation *Animation
+	// Rotation of the Tile in degrees
+	Rotation float32
 }

common/tmx_level.go

@@ -257,6 +257,7 @@ func (l *Level) unpackTiles(x, y, w, h int, d []tmx.Data) []*Tile {
 				X: float32(x),
 				Y: float32(y),
 			}))
+			tile.Rotation = convertFlipToRotation(t.Flipping)
 			ret = append(ret, tile)
 			l.pointMap[mapPoint{X: x, Y: y}] = tile
 			switch l.RenderOrder {
@@ -303,6 +304,7 @@ func (l *Level) unpackTiles(x, y, w, h int, d []tmx.Data) []*Tile {
 					X: float32(x),
 					Y: float32(y),
 				}))
+				tile.Rotation = convertFlipToRotation(t.Flipping)
 				ret = append(ret, tile)
 				l.pointMap[mapPoint{X: x, Y: y}] = tile
 				switch l.RenderOrder {
@@ -384,6 +386,21 @@ func (l *Level) tileFromGID(gid uint32, pt engo.Point) *Tile {
 	return ret
 }
 
+func convertFlipToRotation(flipping uint32) float32 {
+	flip_h := (flipping % tmx.HorizontalFlipFlag) != 0
+	flip_v := (flipping & tmx.VerticalFlipFlag) != 0
+	flip_d := (flipping & tmx.DiagonalFlipFlag) != 0
+	rotation := float32(0.0)
+	if flip_d {
+		rotation = 90
+	}
+	if flip_h && flip_v {
+		rotation += 180
+	}
+
+	return rotation
+}
+
 func getProperties(props []tmx.Property) []Property {
 	ret := make([]Property, 0)
 	for _, p := range props {

common/tmx_level_test.go

@@ -0,0 +1,40 @@
+package common
+
+import "testing"
+
+func TestConvertFlipToRotation(t *testing.T) {
+	tests := []struct {
+		name     string
+		input    uint32
+		expected float32
+	}{
+		{
+			name:     "no flipping should be 0º rotation",
+			input:    0,
+			expected: 0,
+		},
+		{
+			name:     "flipping diagonally should be 90º rotation",
+			input:    2684354560,
+			expected: 90,
+		},
+		{
+			name:     "flipping horizontally and vertically should be 180º rotation",
+			input:    3221225472,
+			expected: 180,
+		},
+		{
+			name:     "flipping diagonally, horizontally and vertically should be 270º rotation",
+			input:    1610612736,
+			expected: 270,
+		},
+	}
+
+	for _, test := range tests {
+		actual := convertFlipToRotation(test.input)
+
+		if actual != test.expected {
+			t.Errorf("%s expected=%f ; got=%f", test.name, test.expected, actual)
+		}
+	}
+}

demos/adventure/adventure.go

@@ -64,7 +64,6 @@ type Tile struct {
 }
 
 func (*DefaultScene) Preload() {
-
 	// Load character model
 	engo.Files.Load(model)
 
@@ -222,7 +221,6 @@ func (scene *DefaultScene) Setup(u engo.Updater) {
 
 	for _, tileLayer := range levelData.TileLayers {
 		for _, tileElement := range tileLayer.Tiles {
-
 			if tileElement.Image != nil {
 				tile := &Tile{BasicEntity: ecs.NewBasic()}
 				tile.RenderComponent = common.RenderComponent{
@@ -231,9 +229,13 @@ func (scene *DefaultScene) Setup(u engo.Updater) {
 				}
 				tile.SpaceComponent = common.SpaceComponent{
 					Position: tileElement.Point,
-					Width:    0,
-					Height:   0,
+					Width:    tileElement.Width(),
+					Height:   tileElement.Height(),
 				}
+				// Rotation of tile around the center
+				center := tile.Center()
+				tile.Rotation = tileElement.Rotation
+				tile.SetCenter(center)
 
 				if tileLayer.Name == "grass" {
 					tile.RenderComponent.SetZIndex(0)
@@ -250,7 +252,6 @@ func (scene *DefaultScene) Setup(u engo.Updater) {
 
 	for _, imageLayer := range levelData.ImageLayers {
 		for _, imageElement := range imageLayer.Images {
-
 			if imageElement.Image != nil {
 				tile := &Tile{BasicEntity: ecs.NewBasic()}
 				tile.RenderComponent = common.RenderComponent{
@@ -401,7 +402,6 @@ func (s *SpeedSystem) Remove(basic ecs.BasicEntity) {
 }
 
 func (s *SpeedSystem) Update(dt float32) {
-
 	for _, e := range s.entities {
 		speed := engo.GameWidth() * dt
 		e.SpaceComponent.Position.X = e.SpaceComponent.Position.X + speed*e.SpeedComponent.Point.X
@@ -422,7 +422,6 @@ func (s *SpeedSystem) Update(dt float32) {
 			e.SpaceComponent.Position.X = widthLimit
 		}
 	}
-
 }
 
 type controlEntity struct {

demos/adventure/assets/example.tmx

@@ -1,22 +1,22 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<map version="1.0" orientation="orthogonal" renderorder="right-down" width="25" height="25" tilewidth="32" tileheight="32" nextobjectid="7">
+<map version="1.5" tiledversion="1.7.1" orientation="orthogonal" renderorder="right-down" width="25" height="25" tilewidth="32" tileheight="32" infinite="0" nextlayerid="4" nextobjectid="7">
  <tileset firstgid="1" name="ts1" tilewidth="32" tileheight="32" tilecount="72" columns="12">
   <image source="grass-tiles-2-small.png" width="384" height="192"/>
  </tileset>
  <tileset firstgid="73" name="ts3" tilewidth="32" tileheight="32" tilecount="64" columns="8">
   <image source="tree2-final.png" width="256" height="256"/>
  </tileset>
- <layer name="grass" width="25" height="25">
+ <layer id="1" name="grass" width="25" height="25">
   <data encoding="base64" compression="zlib">
-   eJztVcsOwzAIS3OH39nu+/9/Wic1kuXYJNp63AHRIoIxj+RorfVTDpBOenyzfVfHKXlp/kd7p/9hU/7ufJUv2wNifGzPBQ/MZ5zLy654VHV1vIZv0NkDsDpgj3Mh4jk+6FthBMXnWmCuiofD4Hpmm3k/IH83ly4+96OK0QGr6ofijTmjKB/sedUPjoUxcVbVjOM8VPu1mu8UeMOOfXHnMTeeI8c725zbas8dZ7WnYXxVPVTfsAaMkcLu7j+15ylE7Zea2YqHwlG+7l59bfJw9w/vdba5Prs8nCT5/MKjesf4rXB+iLUzB99qN88rHnfoO3nsvOd/HrV+A9pgE7E=
+   eJztVUkOgzAMDLmi+MpT2ns/wtN4Sp/WVMLSdDR2opZjD5bB2J6Ml7CUUmqXBaSS9me2z+rWxU7N72iv9O425R/FZ+dle4Mcb9t9wAPP43F22hWPrK4RL/dtFLsAVgVsj2siX8QHfTMMzLeV8uRa4FkVjwiD6+k+a8fw2BucP5rLKD/3I8tRASvrh+KN/FGUD/Y86wfncun1P3p9DqP4btv7tx1nYrRfo/n2muJuuB37EsUjX54j5r2Wz1nG+NGeR5x5Tzf4ruqjeHDfsAaMYcIe3X9qz02I2i81sxkPhaN8o3v1Mckjun9M4Ee7N+IRiZHPLzyy/xj/KyI/xJqZg291NM8jHlfoK3nM/M//PHL9AvxTF38=
   </data>
  </layer>
- <layer name="trees" width="25" height="25">
+ <layer id="2" name="trees" width="25" height="25">
   <data encoding="base64" compression="zlib">
    eJzt1VUOAkEURNFhebi7u7u7y7K5O+jX0xNCCJWcP5JXH12DZX0mbnjghQ9+BBBEyKEbYUQQRQxxJJBEyqF+aWSQRQ55FFBEyaF+ZVRQRQ11NNBES3FD2q+NDrrooY8Bhhgpbkj7jTHBFDPMscASK8UNab81Nthihz0OOOKkuCHtd8YFV9xwxwNPvBQ3TPpJY9JPGpfGb79969KYbF0ak61LY7J1aexuXeet2N2Szluxu6X/W5HH5H9Bml/57kryBi05aII=
   </data>
  </layer>
- <imagelayer name="clouds">
+ <imagelayer id="3" name="clouds">
   <image source="cloud.png" width="400" height="218"/>
  </imagelayer>
 </map>