more work on platform

add sdl texture wrapper
switch viewer to work with platform code

platform/platform.go

@@ -17,11 +17,13 @@ var (
 
 var state struct {
 	isInit  bool
-	windows []*window
+	windows []*Window
 }
 
 type Scene interface {
-	Advance()
+	Init(window *Window) error
+	Advance(window *Window) error
+	Shutdown(window *Window) error
 }
 
 func Init() error {
@@ -75,10 +77,9 @@ func ProcessEvents() error {
 
 	for running := true; running; {
 		advanceWindows()
-		renderWindows()
 
 		for event := sdl.PollEvent(); event != nil; event = sdl.PollEvent() {
-			if !handleEvent(event) {
+			if !processEvent(event) {
 				running = false
 				break
 			}
@@ -90,7 +91,7 @@ func ProcessEvents() error {
 	return nil
 }
 
-func CreateWindow(title string, width, height int, scene Scene) (Window, error) {
+func CreateWindow(title string, width, height int, scene Scene) (*Window, error) {
 	if !state.isInit {
 		return nil, ErrWasNotInit
 	}
@@ -111,13 +112,12 @@ func advanceWindows() {
 	}
 }
 
-func renderWindows() {
+func processEvent(event sdl.Event) bool {
-	for _, window := range state.windows {
+	handled, _ := imgui_backend.ProcessEvent(event)
-		window.render()
+	if handled {
+		return true
 	}
-}
 
-func handleEvent(event sdl.Event) bool {
 	switch event.(type) {
 	case *sdl.QuitEvent:
 		return false

platform/texture.go

@@ -0,0 +1,50 @@
+package platform
+
+import (
+	"image/color"
+	"unsafe"
+
+	"github.com/veandco/go-sdl2/sdl"
+)
+
+type Texture struct {
+	sdlTexture *sdl.Texture
+}
+
+func newTextureFromRgba(renderer *sdl.Renderer, colors []color.RGBA, width, height int) (*Texture, error) {
+	surface, err := sdl.CreateRGBSurfaceFrom(
+		unsafe.Pointer(&colors[0]),
+		int32(width),
+		int32(height),
+		32,
+		width*4,
+		0x000000ff,
+		0x0000ff00,
+		0x00ff0000,
+		0xff000000,
+	)
+
+	if err != nil {
+		return nil, nil
+	}
+
+	sdlTexture, err := renderer.CreateTextureFromSurface(surface)
+	if err != nil {
+		surface.Free()
+	}
+
+	return &Texture{sdlTexture}, nil
+}
+
+func (t *Texture) Destroy() error {
+	if t == nil {
+		return nil
+	}
+
+	if err := t.sdlTexture.Destroy(); err != nil {
+		return err
+	}
+
+	t.sdlTexture = nil
+	return nil
+}

platform/window.go

@@ -1,22 +1,22 @@
 package platform
 
 import (
+	"image/color"
+
+	imgui "github.com/FooSoft/imgui-go"
 	"github.com/FooSoft/lazarus/math"
+	"github.com/FooSoft/lazarus/platform/imgui_backend"
 	"github.com/veandco/go-sdl2/sdl"
 )
 
-type Window interface {
+type Window struct {
-	Destroy() error
-}
-
-type window struct {
 	sdlWindow    *sdl.Window
 	sdlGlContext sdl.GLContext
 	sdlRenderer  *sdl.Renderer
 	scene        Scene
 }
 
-func newWindow(title string, width, height int, scene Scene) (*window, error) {
+func newWindow(title string, width, height int, scene Scene) (*Window, error) {
 	sdlWindow, err := sdl.CreateWindow(
 		title,
 		sdl.WINDOWPOS_CENTERED,
@@ -41,14 +41,25 @@ func newWindow(title string, width, height int, scene Scene) (*window, error) {
 		return nil, err
 	}
 
-	return &window{sdlWindow, sdlGlContext, sdlRenderer, scene}, nil
+	window := &Window{sdlWindow, sdlGlContext, sdlRenderer, scene}
+	if err := scene.Init(window); err != nil {
+		return nil, err
+	}
+
+	return window, nil
 }
 
-func (w *window) Destroy() error {
+func (w *Window) Destroy() error {
-	if w.sdlWindow != nil {
+	if w.sdlWindow == nil {
-		if err := w.sdlWindow.Destroy(); err != nil {
+		return nil
-			return err
+	}
-		}
+
+	if err := w.scene.Shutdown(w); err != nil {
+		return err
+	}
+
+	if err := w.sdlWindow.Destroy(); err != nil {
+		return err
 	}
 
 	w.sdlGlContext = nil
@@ -57,20 +68,33 @@ func (w *window) Destroy() error {
 	return nil
 }
 
-func (w *window) advance() {
+func (w *Window) CreateTextureRgba(colors []color.RGBA, width, height int) (*Texture, error) {
-	w.scene.Advance()
+	return newTextureFromRgba(w.sdlRenderer, colors, width, height)
 }
 
-func (w *window) render() {
+func (w *Window) RenderTexture(texture *Texture, srcRect, dstRect math.Rect4i) {
+	w.sdlRenderer.Copy(
+		texture.sdlTexture,
+		&sdl.Rect{X: int32(srcRect.X), Y: int32(srcRect.Y), W: int32(srcRect.W), H: int32(srcRect.H)},
+		&sdl.Rect{X: int32(dstRect.X), Y: int32(dstRect.Y), W: int32(dstRect.W), H: int32(dstRect.H)},
+	)
+}
+
+func (w *Window) advance() {
+	imgui_backend.NewFrame(w.displaySize())
+	w.scene.Advance(w)
+	imgui.Render()
 	w.sdlWindow.GLMakeCurrent(w.sdlGlContext)
+	imgui_backend.Render(w.displaySize(), w.bufferSize(), imgui.RenderedDrawData())
+	w.sdlWindow.GLSwap()
 }
 
-func (w *window) displaySize() math.Vec2i {
+func (w *Window) displaySize() math.Vec2i {
 	width, height := w.sdlWindow.GetSize()
 	return math.Vec2i{X: int(width), Y: int(height)}
 }
 
-func (w *window) bufferSize() math.Vec2i {
+func (w *Window) bufferSize() math.Vec2i {
 	width, height := w.sdlWindow.GLGetDrawableSize()
 	return math.Vec2i{X: int(width), Y: int(height)}
 }

tools/viewer/main.go

@@ -7,8 +7,8 @@ import (
 
 	"github.com/FooSoft/lazarus/formats/dat"
 	"github.com/FooSoft/lazarus/formats/dc6"
-	"github.com/FooSoft/lazarus/graphics"
+	"github.com/FooSoft/lazarus/math"
-	"github.com/veandco/go-sdl2/sdl"
+	"github.com/FooSoft/lazarus/platform"
 )
 
 func loadPalette(path string) (*dat.Palette, error) {
@@ -29,7 +29,7 @@ func loadSprite(path string) (*dc6.Sprite, error) {
 	return dc6.NewFromReader(fp)
 }
 
-func loadSurface(spritePath, palettePath string) (*sdl.Surface, error) {
+func loadTexture(window *platform.Window, spritePath, palettePath string) (*platform.Texture, error) {
 	sprite, err := loadSprite(spritePath)
 	if err != nil {
 		return nil, err
@@ -48,44 +48,44 @@ func loadSurface(spritePath, palettePath string) (*sdl.Surface, error) {
 		}
 	}
 
-	return graphics.NewSurfaceFromRgba(colors, frame.Width, frame.Height)
+	return window.CreateTextureRgba(colors, frame.Width, frame.Height)
+}
+
+type scene struct {
+	texture *platform.Texture
+}
+
+func (s *scene) Init(window *platform.Window) error {
+	var err error
+	s.texture, err = loadTexture(window, "/home/alex/loadingscreen.dc6", "/home/alex/pal.dat")
+	return err
+}
+
+func (s *scene) Advance(window *platform.Window) error {
+	window.RenderTexture(
+		s.texture,
+		math.Rect4i{X: 0, Y: 0, W: 256, H: 256},
+		math.Rect4i{X: 0, Y: 0, W: 256, H: 256},
+	)
+
+	return nil
+}
+
+func (s *scene) Shutdown(window *platform.Window) error {
+	return s.texture.Destroy()
 }
 
 func main() {
-	window, err := sdl.CreateWindow("Viewer", sdl.WINDOWPOS_UNDEFINED, sdl.WINDOWPOS_UNDEFINED, 800, 600, sdl.WINDOW_SHOWN)
+	platform.Init()
+	defer platform.Shutdown()
+
+	window, err := platform.CreateWindow("Viewer", 1280, 720, new(scene))
 	if err != nil {
 		log.Fatal(err)
 	}
 	defer window.Destroy()
 
-	renderer, err := sdl.CreateRenderer(window, -1, sdl.RENDERER_ACCELERATED)
+	if err := platform.ProcessEvents(); err != nil {
-	if err != nil {
 		log.Fatal(err)
 	}
-	defer renderer.Destroy()
-
-	sprite, err := loadSurface("/home/alex/loadingscreen.dc6", "/home/alex/pal.dat")
-	if err != nil {
-		log.Fatal(err)
-	}
-
-	texture, err := renderer.CreateTextureFromSurface(sprite)
-	if err != nil {
-		log.Fatal(err)
-	}
-
-	renderer.Clear()
-	renderer.Copy(texture, &sdl.Rect{0, 0, 256, 256}, &sdl.Rect{0, 0, 256, 256})
-	renderer.Present()
-
-	for running := true; running; {
-		for event := sdl.PollEvent(); event != nil; event = sdl.PollEvent() {
-			switch event.(type) {
-			case *sdl.QuitEvent:
-				running = false
-				break
-			}
-			sdl.Delay(1)
-		}
-	}
 }