examples/shader: Add build tags for the generated files

Closes #1581

examples/shader/chromaticaberration_go.go

@@ -1,5 +1,7 @@
 // Code generated by file2byteslice. DO NOT EDIT.
 
+// +build example
+
 package main
 
 var chromaticaberration_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\tcenter := ScreenSize / 2\n\tamount := (center - Cursor) / 10 / imageSrcTextureSize()\n\tvar clr vec3\n\tclr.r = imageSrc2At(texCoord + amount).r\n\tclr.g = imageSrc2UnsafeAt(texCoord).g\n\tclr.b = imageSrc2At(texCoord - amount).b\n\treturn vec4(clr, 1.0)\n}\n")

examples/shader/default_go.go

@@ -1,5 +1,7 @@
 // Code generated by file2byteslice. DO NOT EDIT.
 
+// +build example
+
 package main
 
 var default_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\tpos := position.xy/imageDstTextureSize() + Cursor/ScreenSize/4\n\tclr := 0.0\n\tclr += sin(pos.x*cos(Time/15)*80) + cos(pos.y*cos(Time/15)*10)\n\tclr += sin(pos.y*sin(Time/10)*40) + cos(pos.x*sin(Time/25)*40)\n\tclr += sin(pos.x*sin(Time/5)*10) + sin(pos.y*sin(Time/35)*80)\n\tclr *= sin(Time/10) * 0.5\n\treturn vec4(clr, clr*0.5, sin(clr+Time/3)*0.75, 1)\n}\n")

examples/shader/dissolve_go.go

@@ -1,5 +1,7 @@
 // Code generated by file2byteslice. DO NOT EDIT.
 
+// +build example
+
 package main
 
 var dissolve_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\t// Triangle wave to go 0-->1-->0...\n\tlimit := abs(2*fract(Time/3) - 1)\n\tlevel := imageSrc3UnsafeAt(texCoord).x\n\n\t// Add a white border\n\tif limit-0.1 < level && level < limit {\n\t\talpha := imageSrc0UnsafeAt(texCoord).w\n\t\treturn vec4(alpha)\n\t}\n\n\treturn step(limit, level) * imageSrc0UnsafeAt(texCoord)\n}\n")

examples/shader/generate.go

@@ -12,11 +12,13 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+// +build example
+
 package main
 
-//go:generate file2byteslice -package=main -input=default.go -output=default_go.go -var=default_go
-//go:generate file2byteslice -package=main -input=lighting.go -output=lighting_go.go -var=lighting_go
-//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
+//go:generate file2byteslice -package=main -input=default.go -output=default_go.go -var=default_go -buildtags=example
+//go:generate file2byteslice -package=main -input=lighting.go -output=lighting_go.go -var=lighting_go -buildtags=example
+//go:generate file2byteslice -package=main -input=radialblur.go -output=radialblur_go.go -var=radialblur_go -buildtags=example
+//go:generate file2byteslice -package=main -input=chromaticaberration.go -output=chromaticaberration_go.go -var=chromaticaberration_go -buildtags=example
+//go:generate file2byteslice -package=main -input=dissolve.go -output=dissolve_go.go -var=dissolve_go -buildtags=example
+//go:generate file2byteslice -package=main -input=water.go -output=water_go.go -var=water_go -buildtags=example

examples/shader/lighting_go.go

@@ -1,5 +1,7 @@
 // Code generated by file2byteslice. DO NOT EDIT.
 
+// +build example
+
 package main
 
 var lighting_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\tlightpos := vec3(Cursor, 50)\n\tlightdir := normalize(lightpos - position.xyz)\n\tnormal := normalize(imageSrc1UnsafeAt(texCoord) - 0.5)\n\tambient := 0.25\n\tdiffuse := 0.75 * max(0.0, dot(normal.xyz, lightdir))\n\treturn imageSrc0UnsafeAt(texCoord) * (ambient + diffuse)\n}\n")

examples/shader/radialblur_go.go

@@ -1,5 +1,7 @@
 // Code generated by file2byteslice. DO NOT EDIT.
 
+// +build example
+
 package main
 
 var radialblur_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\tdir := normalize(position.xy - Cursor)\n\tclr := imageSrc2UnsafeAt(texCoord)\n\n\tsamples := [...]float{\n\t\t-22, -14, -8, -4, -2, 2, 4, 8, 14, 22,\n\t}\n\tsum := clr\n\tfor i := 0; i < len(samples); i++ {\n\t\tpos := texCoord + dir*samples[i]/imageSrcTextureSize()\n\t\tsum += imageSrc2At(pos)\n\t}\n\tsum /= 10 + 1\n\n\tdist := distance(position.xy, Cursor)\n\tt := clamp(dist/256, 0, 1)\n\treturn mix(clr, sum, t)\n}\n")

examples/shader/water_go.go

@@ -1,5 +1,7 @@
 // Code generated by file2byteslice. DO NOT EDIT.
 
+// +build example
+
 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 imageSrc2UnsafeAt(texCoord)\n\t}\n\n\tsrcsize := imageSrcTextureSize()\n\trorigin, _ := imageSrcRegionOnTexture()\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 := imageSrc2At(vec2(\n\t\ttexCoord.x+xoffset,\n\t\t-(texCoord.y+yoffset-rorigin.y)+bordertex*2+rorigin.y,\n\t)).rgb\n\n\toverlay := vec3(0.5, 1, 1)\n\treturn vec4(mix(clr, overlay, 0.25), 1)\n}\n")