platform and imgui cleanup

platform/imgui/context.go

@@ -15,7 +15,7 @@ type Context struct {
 	bufferSize  math.Vec2i
 }
 
-func CreateContext(displaySize, bufferSize math.Vec2i) (*Context, error) {
+func New(displaySize, bufferSize math.Vec2i) (*Context, error) {
 	singleton.refCount++
 	if singleton.refCount == 1 {
 		singleton.context = imgui.CreateContext(nil)

platform/platform.go

@@ -3,7 +3,6 @@ package platform
 import (
 	"errors"
 	"runtime"
-	"time"
 
 	"github.com/go-gl/gl/v2.1/gl"
 	"github.com/veandco/go-sdl2/sdl"
@@ -46,6 +45,27 @@ func Init() error {
 	return nil
 }
 
+func Advance() (bool, error) {
+	if !singleton.isInit {
+		return false, ErrWasNotInit
+	}
+
+	advanceWindows()
+
+	for event := sdl.PollEvent(); event != nil; event = sdl.PollEvent() {
+		switch event.(type) {
+		case *sdl.QuitEvent:
+			return false, nil
+		default:
+			if err := processWindowEvents(event); err != nil {
+				return false, err
+			}
+		}
+	}
+
+	return true, nil
+}
+
 func Shutdown() error {
 	if !singleton.isInit {
 		return ErrWasNotInit
@@ -68,37 +88,28 @@ func CreateWindow(title string, width, height int, scene Scene) (*Window, error)
 		return nil, ErrWasNotInit
 	}
 
-	window, err := newWindow(title, width, height, scene)
+	w, err := newWindow(title, width, height, scene)
 	if err != nil {
 		return nil, err
 	}
 
-	singleton.windows = append(singleton.windows, window)
-
-	return window, err
+	appendWindow(w)
+	return w, err
 }
 
-func ProcessEvents() error {
-	if !singleton.isInit {
-		return ErrWasNotInit
-	}
+func appendWindow(window *Window) {
+	singleton.windows = append(singleton.windows, window)
+}
 
-	for running := true; running; {
-		advanceWindows()
-
-		for event := sdl.PollEvent(); event != nil; event = sdl.PollEvent() {
-			switch event.(type) {
-			case *sdl.QuitEvent:
-				running = false
-			default:
-				processWindowEvents(event)
-			}
+func removeWindow(window *Window) bool {
+	for i, w := range singleton.windows {
+		if w == window {
+			singleton.windows = append(singleton.windows[:i], singleton.windows[i+1:]...)
+			return true
 		}
-
-		<-time.After(time.Millisecond * 25)
 	}
 
-	return nil
+	return false
 }
 
 func advanceWindows() {
@@ -107,8 +118,12 @@ func advanceWindows() {
 	}
 }
 
-func processWindowEvents(event sdl.Event) {
+func processWindowEvents(event sdl.Event) error {
 	for _, window := range singleton.windows {
-		window.processEvent(event)
+		if _, err := window.processEvent(event); err != nil {
+			return err
+		}
 	}
+
+	return nil
 }

platform/window.go

@@ -1,8 +1,6 @@
 package platform
 
 import (
-	"errors"
-
 	"github.com/FooSoft/lazarus/math"
 	"github.com/FooSoft/lazarus/platform/imgui"
 	"github.com/go-gl/gl/v2.1/gl"
@@ -45,7 +43,7 @@ func newWindow(title string, width, height int, scene Scene) (*Window, error) {
 		scene:        scene,
 	}
 
-	w.imguiContext, err = imgui_backend.CreateContext(w.DisplaySize(), w.BufferSize())
+	w.imguiContext, err = imgui_backend.New(w.DisplaySize(), w.BufferSize())
 	if err != nil {
 		w.Destroy()
 		return nil, err
@@ -77,18 +75,7 @@ func (w *Window) Destroy() error {
 	}
 	w.sdlWindow = nil
 
-	index := -1
-	for i, window := range singleton.windows {
-		if w == window {
-			index = i
-		}
-	}
-
-	if index < 0 {
-		return errors.New("platform does not contain window to destroy")
-	}
-
-	singleton.windows = append(singleton.windows[:index], singleton.windows[index+1:]...)
+	removeWindow(w)
 	return nil
 }
 

tools/viewer/main.go

@@ -3,9 +3,9 @@ package main
 import (
 	"flag"
 	"fmt"
-	"log"
 	"os"
 	"path/filepath"
+	"time"
 
 	imgui "github.com/FooSoft/imgui-go"
 	"github.com/FooSoft/lazarus/formats/dat"
@@ -152,11 +152,21 @@ func main() {
 	scene := &scene{sprite: sprite, palette: palette}
 	window, err := platform.CreateWindow("Viewer", 1280, 720, scene)
 	if err != nil {
-		log.Fatal(err)
+		fmt.Fprintln(os.Stderr, err)
+		os.Exit(1)
 	}
 	defer window.Destroy()
 
-	if err := platform.ProcessEvents(); err != nil {
-		log.Fatal(err)
+	for {
+		run, err := platform.Advance()
+		if err != nil {
+			fmt.Fprintln(os.Stderr, err)
+			os.Exit(1)
+		}
+		if !run {
+			break
+		}
+
+		<-time.After(time.Millisecond * 25)
 	}
 }