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Diffstat (limited to 'vendor/github.com/llgcode/draw2d/samples/postscriptgl/postscriptgl.go')
-rw-r--r--vendor/github.com/llgcode/draw2d/samples/postscriptgl/postscriptgl.go114
1 files changed, 114 insertions, 0 deletions
diff --git a/vendor/github.com/llgcode/draw2d/samples/postscriptgl/postscriptgl.go b/vendor/github.com/llgcode/draw2d/samples/postscriptgl/postscriptgl.go
new file mode 100644
index 0000000..9e75adb
--- /dev/null
+++ b/vendor/github.com/llgcode/draw2d/samples/postscriptgl/postscriptgl.go
@@ -0,0 +1,114 @@
+// Open a OpenGL window and display a tiger interpreting a postscript file
+package main
+
+import (
+ "io/ioutil"
+ "log"
+ "math"
+ "os"
+ "runtime"
+ "strings"
+ "time"
+
+ "github.com/go-gl/gl/v2.1/gl"
+ "github.com/go-gl/glfw/v3.1/glfw"
+ "github.com/llgcode/draw2d/draw2dgl"
+ "github.com/llgcode/ps"
+)
+
+var postscriptContent string
+
+var (
+ width, height int
+ rotate int
+ window *glfw.Window
+)
+
+func reshape(window *glfw.Window, w, h int) {
+ gl.ClearColor(1, 1, 1, 1)
+ //fmt.Println(gl.GetString(gl.EXTENSIONS))
+ gl.Viewport(0, 0, int32(w), int32(h)) /* Establish viewing area to cover entire window. */
+ gl.MatrixMode(gl.PROJECTION) /* Start modifying the projection matrix. */
+ gl.LoadIdentity() /* Reset project matrix. */
+ gl.Ortho(0, float64(w), 0, float64(h), -1, 1) /* Map abstract coords directly to window coords. */
+ gl.Scalef(1, -1, 1) /* Invert Y axis so increasing Y goes down. */
+ gl.Translatef(0, float32(-h), 0) /* Shift origin up to upper-left corner. */
+ gl.Enable(gl.BLEND)
+ gl.BlendFunc(gl.SRC_ALPHA, gl.ONE_MINUS_SRC_ALPHA)
+ gl.Disable(gl.DEPTH_TEST)
+ width, height = w, h
+}
+
+func display() {
+
+ gl.Clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT)
+
+ lastTime := time.Now()
+ gl.LineWidth(1)
+ gc := draw2dgl.NewGraphicContext(width, height)
+
+ gc.Translate(380, 400)
+ gc.Scale(1, -1)
+ rotate = (rotate + 1) % 360
+ gc.Rotate(float64(rotate) * math.Pi / 180)
+ gc.Translate(-380, -400)
+
+ interpreter := ps.NewInterpreter(gc)
+ reader := strings.NewReader(postscriptContent)
+
+ interpreter.Execute(reader)
+ dt := time.Now().Sub(lastTime)
+ log.Printf("Redraw in : %f ms\n", float64(dt)*1e-6)
+ gl.Flush() /* Single buffered, so needs a flush. */
+}
+
+func main() {
+ src, err := os.OpenFile("tiger.ps", 0, 0)
+ if err != nil {
+ log.Println("can't find postscript file.")
+ return
+ }
+ defer src.Close()
+ bytes, err := ioutil.ReadAll(src)
+ postscriptContent = string(bytes)
+ err = glfw.Init()
+ if err != nil {
+ panic(err)
+ }
+ defer glfw.Terminate()
+
+ window, err = glfw.CreateWindow(800, 800, "Show Tiger in OpenGL", nil, nil)
+ if err != nil {
+ panic(err)
+ }
+
+ window.MakeContextCurrent()
+ window.SetSizeCallback(reshape)
+ window.SetKeyCallback(onKey)
+
+ glfw.SwapInterval(1)
+
+ err = gl.Init()
+ if err != nil {
+ panic(err)
+ }
+ reshape(window, 800, 800)
+ for !window.ShouldClose() {
+ display()
+ window.SwapBuffers()
+ glfw.PollEvents()
+ // time.Sleep(2 * time.Second)
+ }
+}
+
+func onKey(w *glfw.Window, key glfw.Key, scancode int, action glfw.Action, mods glfw.ModifierKey) {
+ switch {
+ case key == glfw.KeyEscape && action == glfw.Press,
+ key == glfw.KeyQ && action == glfw.Press:
+ w.SetShouldClose(true)
+ }
+}
+
+func init() {
+ runtime.LockOSThread()
+}