Add ImGui through cimgui-go

https://github.com/AllenDang/cimgui-go

.gitignore

@@ -1,2 +1,2 @@
 rom.gb
-
+imgui.ini

gb/cartridge.go

@@ -1,6 +1,7 @@
 package gb
 
 import (
+	"bytes"
 	"encoding/binary"
 	"io"
 	"log"
@@ -53,7 +54,7 @@ var cartridgeTypes = map[byte]string{
 // RAM sizes
 // https://gbdev.io/pandocs/The_Cartridge_Header.html#0149--ram-size
 var ramSizes = map[byte]string{
-	0x00: "0 - No RAM ",
+	0x00: "0 - No RAM",
 	0x01: "UNUSED VALUE",
 	0x02: "8 KiB - 1 bank",
 	0x03: "32 KiB - 4 banks of 8 KiB each",
@@ -244,7 +245,7 @@ type Cartridge struct {
 }
 
 func Insert(filename string) Cartridge {
-	file, err := os.Open("rom.gb")
+	file, err := os.Open(filename)
 	if err != nil {
 		log.Fatal(err)
 	}
@@ -270,7 +271,7 @@ func Insert(filename string) Cartridge {
 	}
 
 	// Convert some header values
-	cartridge.Title = string(header.Title[:])
+	cartridge.Title = string(bytes.Trim(header.Title[:], "\x00"))
 	cartridge.Mapper = cartridgeTypes[header.CartridgeType]
 	if header.OldLicenseeCode == 0x33 {
 		// FIXME(m): Support new licensee codes

gb/cartridge_test.go

@@ -0,0 +1,21 @@
+package gb
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestInsertCartridge(t *testing.T) {
+	cartridge := Insert("../rom.gb")
+	assert := assert.New(t)
+
+	assert.Equal(cartridge.Title, "SEIKEN DENSETSU")
+	assert.Equal(cartridge.Mapper, "MBC2+BATTERY")
+	assert.Equal(cartridge.Licensee, "Square")
+	assert.False(cartridge.SGBSupport, "SGB support should be false")
+	assert.Equal(cartridge.ROMSize, 256)
+	assert.Equal(cartridge.RAMSize, "0 - No RAM")
+	assert.Equal(cartridge.Destination, "Overseas only")
+	assert.Equal(cartridge.Version, 0)
+}

gb/cpu.go

@@ -0,0 +1,21 @@
+package gb
+
+type Cpu struct {
+	A     uint8
+	Flags uint8
+	BC    uint16
+	DE    uint16
+	HL    uint16
+	SP    uint16
+	PC    uint16
+}
+
+func Reset() Cpu {
+	cpu := Cpu{}
+
+	return cpu
+}
+
+func Tick(cpu *Cpu) {
+	cpu.PC++
+}

go.mod

@@ -1,3 +1,14 @@
 module gb-player
 
 go 1.24.5
+
+require (
+	github.com/AllenDang/cimgui-go v1.3.1
+	github.com/stretchr/testify v1.10.0
+)
+
+require (
+	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/pmezard/go-difflib v1.0.0 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
+)

go.sum

@@ -0,0 +1,12 @@
+github.com/AllenDang/cimgui-go v1.3.1 h1:2f33a7GHJwRofH0CRQbUTXywazfph/K5LQLKyOBv24k=
+github.com/AllenDang/cimgui-go v1.3.1/go.mod h1:Fuj3G2E3zd2bMQxmhuSPSFFl41MwS+MhyZ6DHgYq/YM=
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/stretchr/testify v1.10.0 h1:Xv5erBjTwe/5IxqUQTdXv5kgmIvbHo3QQyRwhJsOfJA=
+github.com/stretchr/testify v1.10.0/go.mod h1:r2ic/lqez/lEtzL7wO/rwa5dbSLXVDPFyf8C91i36aY=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

main.go

@@ -2,17 +2,81 @@ package main
 
 import (
 	"fmt"
+	"log"
+	"runtime"
+
 	"gb-player/gb"
+
+	"github.com/AllenDang/cimgui-go/backend"
+	"github.com/AllenDang/cimgui-go/backend/sdlbackend"
+	"github.com/AllenDang/cimgui-go/imgui"
 )
 
-func main() {
-	cartridge := gb.Insert("rom.gb")
-	fmt.Println("Title:", cartridge.Title)
-	fmt.Println("Mapper:", cartridge.Mapper)
-	fmt.Println("Licensee:", cartridge.Licensee)
-	fmt.Println("Super Game Boy support?", cartridge.SGBSupport)
-	fmt.Println("ROM size:", cartridge.ROMSize, "bytes")
-	fmt.Println("RAM size:", cartridge.RAMSize)
-	fmt.Println("Publication destination:", cartridge.Destination)
-	fmt.Println("ROM version:", cartridge.Version)
+var currentBackend backend.Backend[sdlbackend.SDLWindowFlags]
+
+func init() {
+	runtime.LockOSThread()
+}
+
+func showDebugWindow() {
+	imgui.Text(fmt.Sprintf("Framerate: %.1f FPS", imgui.CurrentIO().Framerate()))
+}
+
+func showROMWindow(cartridge *gb.Cartridge) {
+	imgui.Begin("ROM")
+
+	imgui.Text(fmt.Sprintf("Title: %s", cartridge.Title))
+	imgui.Text(fmt.Sprintf("Mapper: %s", cartridge.Mapper))
+	imgui.Text(fmt.Sprintf("Licensee: %s", cartridge.Licensee))
+	if cartridge.SGBSupport {
+		imgui.Text("Super Game Boy support?: Yes")
+	} else {
+		imgui.Text("Super Game Boy support?: No")
+	}
+	imgui.Text(fmt.Sprintf("ROM size: %d bytes", cartridge.ROMSize))
+	imgui.Text(fmt.Sprintf("RAM size: %s", cartridge.RAMSize))
+	imgui.Text(fmt.Sprintf("Publication: %s", cartridge.Destination))
+	imgui.Text(fmt.Sprintf("ROM version: %d", cartridge.Version))
+
+	imgui.End()
+}
+
+func showCPUWindow(cpu *gb.Cpu) {
+	imgui.Begin("CPU")
+
+	imgui.Text(fmt.Sprintf("PC: %d", cpu.PC))
+
+	imgui.End()
+}
+
+func main() {
+	currentBackend, err := backend.CreateBackend(sdlbackend.NewSDLBackend())
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	currentBackend.SetBgColor(imgui.NewVec4(0.45, 0.55, 0.6, 1.0))
+
+	currentBackend.CreateWindow("GB Player", 1200, 900)
+
+	currentBackend.SetDropCallback(func(p []string) {
+		fmt.Printf("drop triggered: %v", p)
+	})
+
+	currentBackend.SetCloseCallback(func() {
+		fmt.Println("window is closing")
+	})
+
+	cartridge := gb.Insert("rom.gb")
+	cpu := gb.Reset()
+
+	currentBackend.Run(func() {
+		imgui.ClearSizeCallbackPool()
+
+		gb.Tick(&cpu)
+
+		showDebugWindow()
+		showROMWindow(&cartridge)
+		showCPUWindow(&cpu)
+	})
 }