examples/shader: Add water.go

Updates #1284

examples/shader/generate.go

@@ -19,3 +19,4 @@ package main
 //go:generate file2byteslice -package=main -input=radialblur.go -output=radialblur_go.go -var=radialblur_go
 //go:generate file2byteslice -package=main -input=chromaticaberration.go -output=chromaticaberration_go.go -var=chromaticaberration_go
 //go:generate file2byteslice -package=main -input=dissolve.go -output=dissolve_go.go -var=dissolve_go
+//go:generate file2byteslice -package=main -input=water.go -output=water_go.go -var=water_go

examples/shader/main.go

@@ -87,6 +87,7 @@ var shaderSrcs = [][]byte{
 	radialblur_go,
 	chromaticaberration_go,
 	dissolve_go,
+	water_go,
 }
 
 type Game struct {

examples/shader/water.go

@@ -0,0 +1,42 @@
+// Copyright 2020 The Ebiten Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// +build ignore
+
+package main
+
+var Time float
+var Cursor vec2
+var ScreenSize vec2
+
+func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
+	border := ScreenSize.y*0.6 + 4*cos(Time*3+texCoord.y*200)
+	if position.y < border {
+		return image2TextureAt(texCoord)
+	}
+
+	srcsize := imageSrcTextureSize()
+	rorigin, rsize := imageSrcTextureSourceRegion()
+
+	xoffset := (4 / srcsize.x) * cos(Time*3+texCoord.y*200)
+	yoffset := (20 / srcsize.y) * (1.0 + cos(Time*3+texCoord.y*50))
+	bordertex := border / srcsize.y
+	clr := vec4(image2TextureBoundsAt(vec2(
+		texCoord.x+xoffset,
+		-(texCoord.y+yoffset-rorigin.y)+bordertex*2+rorigin.y,
+	)))
+
+	overlay := vec4(0.5, 1, 1, 1)
+	return mix(clr, overlay, 0.25)
+}

examples/shader/water_go.go

@@ -0,0 +1,5 @@
+// Code generated by file2byteslice. DO NOT EDIT.
+
+package main
+
+var water_go = []byte("// Copyright 2020 The Ebiten Authors\n//\n// Licensed under the Apache License, Version 2.0 (the \"License\");\n// you may not use this file except in compliance with the License.\n// You may obtain a copy of the License at\n//\n//     http://www.apache.org/licenses/LICENSE-2.0\n//\n// Unless required by applicable law or agreed to in writing, software\n// distributed under the License is distributed on an \"AS IS\" BASIS,\n// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.\n// See the License for the specific language governing permissions and\n// limitations under the License.\n\n// +build ignore\n\npackage main\n\nvar Time float\nvar Cursor vec2\nvar ScreenSize vec2\n\nfunc Fragment(position vec4, texCoord vec2, color vec4) vec4 {\n\tborder := ScreenSize.y*0.6 + 4*cos(Time*3+texCoord.y*200)\n\tif position.y < border {\n\t\treturn image2TextureAt(texCoord)\n\t}\n\n\tsrcsize := imageSrcTextureSize()\n\trorigin, rsize := imageSrcTextureSourceRegion()\n\n\txoffset := (4 / srcsize.x) * cos(Time*3+texCoord.y*200)\n\tyoffset := (20 / srcsize.y) * (1.0 + cos(Time*3+texCoord.y*50))\n\tbordertex := border / srcsize.y\n\tclr := vec4(image2TextureBoundsAt(vec2(\n\t\ttexCoord.x+xoffset,\n\t\t-(texCoord.y+yoffset-rorigin.y)+bordertex*2+rorigin.y,\n\t)))\n\n\toverlay := vec4(0.5, 1, 1, 1)\n\treturn mix(clr, overlay, 0.25)\n}\n")