More .obj investigating. 0x80 seems to be a special value

cmd/view-obj/main.go

@@ -0,0 +1,134 @@
+package main
+
+import (
+	"flag"
+	"log"
+	"math"
+	"os"
+	"path/filepath"
+
+	"github.com/faiface/pixel"
+	"github.com/faiface/pixel/pixelgl"
+	"golang.org/x/image/colornames"
+
+	"ur.gs/ordoor/internal/conv"
+	"ur.gs/ordoor/internal/data"
+	"ur.gs/ordoor/internal/ui"
+)
+
+var (
+	gamePath = flag.String("game-path", "./orig", "Path to a WH40K: Chaos Gate installation")
+	objFile  = flag.String("obj", "", "Path to a .obj file, e.g. ./orig/Obj/TZEENTCH.OBJ")
+)
+
+type env struct {
+	obj *conv.Object
+}
+
+type state struct {
+	env *env
+
+	step      int
+	spriteIdx int
+
+	zoom float64
+
+	cam    pixel.Matrix
+	camPos pixel.Vec
+}
+
+func main() {
+	flag.Parse()
+
+	if *gamePath == "" || *objFile == "" {
+		flag.Usage()
+		os.Exit(1)
+	}
+
+	rawObj, err := data.LoadObject(*objFile)
+	if err != nil {
+		log.Fatalf("Failed to load %s: %v", *objFile, err)
+	}
+	obj := conv.ConvertObject(rawObj, filepath.Base(*objFile))
+
+	env := &env{obj: obj}
+
+	// The main thread now belongs to pixelgl
+	pixelgl.Run(env.run)
+}
+
+func (e *env) run() {
+	win, err := ui.NewWindow("View Object: " + *objFile)
+	if err != nil {
+		log.Fatal("Couldn't create window: %v", err)
+	}
+
+	pWin := win.PixelWindow
+	state := &state{
+		env:    e,
+		camPos: pixel.V(0, float64(-pWin.Bounds().Size().Y)),
+		zoom:   8.0,
+	}
+
+	// For now, just try to display the various objects
+	// left + right to change object, up + down to change frame
+	win.Run(func() {
+		oldState := *state
+		state = state.runStep(pWin)
+
+		if oldState != *state || oldState.step == 0 {
+			log.Printf(
+				"new state: numSprites=%d sprite=%d zoom=%.2f",
+				len(state.env.obj.Sprites),
+				state.spriteIdx,
+				state.zoom,
+			)
+			state.present(pWin)
+		}
+
+		state.step += 1
+	})
+}
+
+func (s *state) runStep(pWin *pixelgl.Window) *state {
+	newState := *s
+	newState.handleKeys(pWin)
+
+	return &newState
+}
+
+func (s *state) present(pWin *pixelgl.Window) {
+	obj := s.env.obj
+	sprite := obj.Sprites[s.spriteIdx]
+
+	center := pWin.Bounds().Center()
+
+	cam := pixel.IM
+	cam = cam.ScaledXY(center, pixel.Vec{1.0, -1.0}) // invert the Y axis
+	cam = cam.Scaled(center, s.zoom)                 // apply current zoom factor
+	//cam = cam.Moved(center.Sub(s.camPos))           // Make it central
+	//cam = cam.Rotated(center, -0.785) // Apply isometric angle
+	s.cam = cam
+	pWin.SetMatrix(s.cam)
+
+	pWin.Clear(colornames.Black)
+	pixel.NewSprite(sprite.Pic, sprite.Pic.Bounds()).Draw(pWin, pixel.IM.Moved(center))
+}
+
+func (s *state) handleKeys(pWin *pixelgl.Window) {
+
+	if pWin.JustPressed(pixelgl.KeyMinus) {
+		if s.spriteIdx > 0 {
+			s.spriteIdx -= 1
+		}
+	}
+
+	if pWin.JustPressed(pixelgl.KeyEqual) {
+		if s.spriteIdx < len(s.env.obj.Sprites)-1 {
+			s.spriteIdx += 1
+		}
+	}
+
+	// Zoom in and out with the mouse wheel
+	s.zoom *= math.Pow(1.2, pWin.MouseScroll().Y)
+}