ebiten/example/game.go
2013-12-08 21:03:30 +09:00

140 lines
3.3 KiB
Go

package main
import (
"fmt"
"github.com/hajimehoshi/go-ebiten/graphics"
"github.com/hajimehoshi/go-ebiten/graphics/matrix"
"github.com/hajimehoshi/go-ebiten/ui"
"image/color"
"math"
)
var TexturePaths = map[string]string{
"ebiten": "images/ebiten.png",
"text": "images/text.png",
}
type drawInfo struct {
textures map[string]graphics.TextureId
inputStr string
textureX int
textureY int
textureAngle float64
textureGeo matrix.Geometry
}
type Game struct {
inputX int
inputY int
inputPrevX int
inputPrevY int
counter int
drawInfo
}
func NewGame() *Game {
return &Game{
inputX: -1,
inputY: -1,
inputPrevX: -1,
inputPrevY: -1,
counter: 0,
drawInfo: drawInfo{
textures: map[string]graphics.TextureId{},
textureX: 0,
textureY: 0,
textureAngle: 0,
textureGeo: matrix.IdentityGeometry(),
},
}
}
func (game *Game) OnTextureCreated(e graphics.TextureCreatedEvent) {
if e.Error != nil {
panic(e.Error)
}
game.textures[e.Tag.(string)] = e.Id
}
func (game *Game) OnInputStateUpdated(e ui.InputStateUpdatedEvent) {
game.inputX, game.inputY = e.X, e.Y
}
func (game *Game) Update() {
const textureWidth = 57
const textureHeight = 26
game.counter++
game.drawInfo.inputStr = fmt.Sprintf(`Input State:
X: %d
Y: %d`, game.inputX, game.inputY)
if game.inputPrevX != -1 && game.inputPrevY != -1 &&
game.inputX != -1 && game.inputY != -1 {
dx, dy := game.inputX-game.inputPrevX, game.inputY-game.inputPrevY
game.textureX += dx
game.textureY += dy
}
game.drawInfo.textureAngle = 2 * math.Pi * float64(game.counter) / 600
game.drawInfo.textureGeo = matrix.IdentityGeometry()
game.drawInfo.textureGeo.Translate(-textureWidth/2, -textureHeight/2)
game.drawInfo.textureGeo.Rotate(game.drawInfo.textureAngle)
game.drawInfo.textureGeo.Translate(textureWidth, textureHeight)
game.drawInfo.textureGeo.Translate(float64(game.textureX), float64(game.textureY))
// Update for the next frame.
game.inputPrevX, game.inputPrevY = game.inputX, game.inputY
}
func (game *Game) Draw(g graphics.Canvas) {
if len(game.drawInfo.textures) < len(TexturePaths) {
return
}
g.Fill(128, 128, 255)
game.drawTexture(g, game.drawInfo.textureGeo, matrix.IdentityColor())
game.drawText(g, game.drawInfo.inputStr, 6, 6, &color.RGBA{0x0, 0x0, 0x0, 0x80})
game.drawText(g, game.drawInfo.inputStr, 5, 5, color.White)
}
func (game *Game) drawText(g graphics.Canvas, text string, x, y int, clr color.Color) {
const letterWidth = 6
const letterHeight = 16
parts := []graphics.TexturePart{}
textX := 0
textY := 0
for _, c := range text {
if c == '\n' {
textX = 0
textY += letterHeight
continue
}
code := int(c)
x := (code % 32) * letterWidth
y := (code / 32) * letterHeight
source := graphics.Rect{x, y, letterWidth, letterHeight}
parts = append(parts, graphics.TexturePart{
LocationX: textX,
LocationY: textY,
Source: source,
})
textX += letterWidth
}
geometryMatrix := matrix.IdentityGeometry()
geometryMatrix.Translate(float64(x), float64(y))
colorMatrix := matrix.IdentityColor()
colorMatrix.Scale(clr)
g.DrawTextureParts(game.drawInfo.textures["text"], parts,
geometryMatrix, colorMatrix)
}
func (game *Game) drawTexture(g graphics.Canvas, geo matrix.Geometry, color matrix.Color) {
g.DrawTexture(game.drawInfo.textures["ebiten"], geo, color)
}