2D GUI (#20)

assets/ui/helloworld.xml

@@ -0,0 +1,9 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<List xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+    xsi:noNamespaceSchemaLocation="schema.xsd"
+    orientation="vertical">
+    <Text id="counter" color="#ff1493">0</Text>
+    <Button id="btn">
+        <Text>Click me!</Text>
+    </Button>
+</List>

assets/ui/schema.xsd

@@ -0,0 +1,61 @@
+<?xml version="1.0" encoding="utf-8"?>
+<xs:schema attributeFormDefault="unqualified" elementFormDefault="qualified"
+    xmlns:xs="http://www.w3.org/2001/XMLSchema">
+
+    <xs:element name="Image">
+        <xs:complexType>
+            <xs:attribute name="src" type="xs:string" use="required" />
+            <xs:attribute name="width" type="xs:string" use="required" />
+            <xs:attribute name="height" type="xs:string" use="required" />
+            <xs:attribute name="id" type="xs:string" />
+        </xs:complexType>
+    </xs:element>
+
+    <xs:element name="Text">
+        <xs:complexType>
+            <xs:simpleContent>
+                <xs:extension base="xs:string">
+                    <xs:attribute name="id" type="xs:string" />
+                    <xs:attribute name="font" type="xs:string" />
+                </xs:extension>
+            </xs:simpleContent>
+        </xs:complexType>
+    </xs:element>
+
+    <!-- -->
+
+    <xs:element name="List">
+        <xs:complexType>
+            <xs:sequence>
+                <xs:any minOccurs="1" maxOccurs="unbounded" processContents="strict" />
+            </xs:sequence>
+            <xs:attribute name="orientation" use="required">
+                <xs:simpleType>
+                    <xs:restriction base="xs:string">
+                        <xs:enumeration value="vertical" />
+                        <xs:enumeration value="horizontal" />
+                    </xs:restriction>
+                </xs:simpleType>
+            </xs:attribute>
+        </xs:complexType>
+    </xs:element>
+
+    <xs:element name="Button">
+        <xs:complexType>
+            <xs:sequence>
+                <xs:any minOccurs="1" maxOccurs="1" processContents="strict" />
+            </xs:sequence>
+            <xs:attribute name="id" use="required" />
+        </xs:complexType>
+    </xs:element>
+
+    <!-- Document / Root  needs at least ParentElement or ChildElement-->
+
+    <xs:element name="Document">
+        <xs:complexType>
+            <xs:sequence>
+                <xs:any minOccurs="1" maxOccurs="unbounded" processContents="strict" />
+            </xs:sequence>
+        </xs:complexType>
+    </xs:element>
+</xs:schema>

cmd/game/main.go

@@ -13,7 +13,7 @@ func main() {
 
 	l, err := level.Load("assets/levels/level1.bmlvl")
 	if err != nil {
-		panic(err)
+		log.Fatal(err)
 	}
 	level.Set(l)
 
@@ -25,7 +25,6 @@ func main() {
 
 	// game loop
 	for core.Running() {
-		firstperson.GetMouseInput()
 		firstperson.MovePlayer()
 		err = firstperson.RenderViewport()
 		if err != nil {

engine/core/window.go

@@ -17,6 +17,8 @@
 package core
 
 import (
+	"runtime"
+
 	"github.com/charmbracelet/log"
 	"github.com/veandco/go-sdl2/sdl"
 )
@@ -143,6 +145,8 @@ func Start(t string) {
 		log.Fatal("window already started")
 	}
 
+	runtime.LockOSThread()
+
 	var err error
 
 	title = t
@@ -229,6 +233,7 @@ func Stop() {
 	_ = window.Destroy()
 	_ = renderer.Destroy()
 	sdl.Quit()
+	log.Print("Engine stopped")
 }
 
 // Running returns whether the game loop should continue or not.
@@ -242,7 +247,33 @@ func Running() bool {
 	return running
 }
 
+// Mouse states.
+var (
+	// MouseX is the current X position of the mouse.
+	MouseX int32
+	// MouseY is the current Y position of the mouse.
+	MouseY int32
+	// MouseDeltaX is the change in X position of the mouse since the last frame.
+	MouseDeltaX int32
+	// MouseDeltaY is the change in Y position of the mouse since the last frame.
+	MouseDeltaY int32
+	// MouseState is the current state of the mouse.
+	MouseState uint32
+)
+
 func eventLoop() {
+	var mouseX, mouseY int32
+	mouseX, mouseY, MouseState = sdl.GetMouseState()
+	if cursorLocked {
+		MouseDeltaX = mouseX - MouseX
+		MouseDeltaY = mouseY - MouseY
+	} else {
+		MouseDeltaX = 0
+		MouseDeltaY = 0
+	}
+	MouseX = mouseX
+	MouseY = mouseY
+
 	keyStates = sdl.GetKeyboardState()
 	for event := sdl.PollEvent(); event != nil; event = sdl.PollEvent() {
 		switch event.GetType() {
@@ -257,13 +288,30 @@ func eventLoop() {
 // Present draws the frame to the screen.
 // Call this at the very end of the game loop.
 func Present() {
+	if cursorHover {
+		sdl.SetCursor(sdl.CreateSystemCursor(sdl.SYSTEM_CURSOR_HAND))
+	} else {
+		sdl.SetCursor(sdl.CreateSystemCursor(sdl.SYSTEM_CURSOR_ARROW))
+	}
 	renderer.Present()
 	frameTime := uint32(sdl.GetTicks64() - frameStartTime)
 	if frameTime < targetFrameTime {
 		sdl.Delay(targetFrameTime - frameTime)
 	}
+
+	cursorHover = false
 }
 
 func FPS() float32 {
 	return 1.0 / DeltaTime
 }
+
+func ScreenRect() *sdl.Rect {
+	return &sdl.Rect{W: width, H: height}
+}
+
+var cursorHover = false
+
+func NotifyCursorHover() {
+	cursorHover = true
+}

engine/firstperson/input.go

@@ -33,28 +33,12 @@ const (
 	turnSpeed  float32 = 0.1
 )
 
-var (
-	MouseX      int32
-	MouseDeltaX int32
-	MouseState  uint32
-)
-
-func GetMouseInput() {
-	MouseX, _, MouseState = sdl.GetMouseState()
-	if core.IsCursorLocked() {
-		MouseDeltaX = MouseX - core.CenterX()
-		core.Window().WarpMouseInWindow(core.CenterX(), core.CenterY())
-	} else {
-		MouseDeltaX = 0
-	}
-}
-
 func KeyDown(key uint8) bool {
 	return core.KeyStates()[key] != 0
 }
 
 func MovePlayer() {
-	core.P.Angle += float32(MouseDeltaX) * turnSpeed * core.DeltaTime
+	core.P.Angle += float32(core.MouseDeltaX) * turnSpeed * core.DeltaTime
 
 	if KeyDown(KeyForward) {
 		core.P.Speed = 1

engine/firstperson/window.go

@@ -18,13 +18,11 @@ package firstperson
 
 import (
 	"github.com/bloodmagesoftware/bloodmage-engine/engine/core"
-	"github.com/bloodmagesoftware/bloodmage-engine/engine/level"
 	"github.com/charmbracelet/log"
 	"github.com/chewxy/math32"
 )
 
 func Init() {
-	level.CollisionRound = 0.125
 	f := func() {
 		log.Debug("firstperson window resize")
 		screenDist = core.HalfWidthF() / math32.Tan(halfFov)

engine/font/register.go

@@ -14,28 +14,101 @@
 // You should have received a copy of the GNU General Public License
 // along with this program. If not, see <https://github.com/bloodmagesoftware/bloodmage-engine/blob/main/LICENSE.md>.
 
+// Package font is for dealing with ttf fonts in the ui.
+//
+// Call font.Init() before using any other font function.
+// Call font.Quit() at the end of your game.
 package font
 
 import (
-	"github.com/bloodmagesoftware/bloodmage-engine/engine/textures"
+	"fmt"
+	"os"
+
+	"github.com/veandco/go-sdl2/ttf"
+)
+
+var (
+	// fonts holds all registered fonts wether they are currently loaded or not.
+	fonts map[string]*font
+	// defaultFont is the font that is used when no other font is specified.
+	defaultFont *font
 )
 
 type font struct {
-	startChar    uint32
-	endChar      uint32
-	texture      *textures.Texture
-	charWidth    int32
-	charHeight   int32
-	collumnCount int32
-}
-
-func Load(texturePath string, startChar uint32, endChar uint32, charWidth int32, charHeight int32, collumnCount int32) *font {
-	return &font{
-		startChar:    startChar,
-		endChar:      endChar,
-		texture:      textures.Unregistered(texturePath),
-		charWidth:    charWidth,
-		charHeight:   charHeight,
-		collumnCount: collumnCount,
+	path string
+	ttf  *ttf.Font
+}
+
+// Font ensures the font is loaded and returns it.
+func (f *font) Font() (*ttf.Font, error) {
+	if f.ttf != nil {
+		return f.ttf, nil
+	}
+
+	font, err := ttf.OpenFont(f.path, 32)
+	if err != nil {
+		return nil, err
+	}
+	f.ttf = font
+
+	return font, nil
+}
+
+func Init() error {
+	return ttf.Init()
+}
+
+// Quit closes all loaded fonts.
+// After calling this function you can no longer use any font functions before calling Init() again.
+func Quit() {
+	for _, font := range fonts {
+		if font.ttf != nil {
+			font.ttf.Close()
+			font.ttf = nil
+		}
+	}
+	ttf.Quit()
+}
+
+func Register(fontPath string, name string) error {
+	if fonts == nil {
+		fonts = make(map[string]*font)
+	}
+	if _, ok := fonts[name]; ok {
+		return fmt.Errorf("font %s already registered", name)
+	}
+	// check if file exists with os.Stat()
+	if _, err := os.Stat(fontPath); err != nil {
+		if os.IsNotExist(err) {
+			return fmt.Errorf("font %s does not exist", fontPath)
+		} else {
+			return fmt.Errorf("error checking if font %s exists: %s", fontPath, err)
+		}
+	}
+	fonts[name] = &font{
+		path: fontPath,
+	}
+	return nil
+}
+
+func SetDefault(name string) error {
+	if _, ok := fonts[name]; !ok {
+		return fmt.Errorf("font %s not registered", name)
+	}
+	defaultFont = fonts[name]
+	return nil
+}
+
+func Default() (*ttf.Font, error) {
+	if defaultFont != nil {
+		return defaultFont.Font()
+	}
+	return nil, fmt.Errorf("no default font set")
+}
+
+func Get(name string) (*ttf.Font, error) {
+	if font, ok := fonts[name]; ok {
+		return font.Font()
 	}
+	return nil, fmt.Errorf("font %s not registered", name)
 }