doodle/pkg/level/chunk.go
Noah Petherbridge 9e4f34864d Remove MsgPack, Fix doodad display on top/left edges
* Clean up unused msgpack code for levels and doodads
* Fix the cosmetic bug where actors in your level would display wrongly
  when scrolling off the top/left edges of the screen: they used to
  anchor at their own 0,0 coordinate and crop their width/height leading
  to a 'scrolling' effect that didn't happen on the right/bottom edges.
2022-01-09 13:16:29 -08:00

311 lines
7.8 KiB
Go

package level
import (
"encoding/json"
"fmt"
"image"
"math"
"git.kirsle.net/apps/doodle/pkg/balance"
"git.kirsle.net/apps/doodle/pkg/log"
"git.kirsle.net/apps/doodle/pkg/pattern"
"git.kirsle.net/apps/doodle/pkg/shmem"
"git.kirsle.net/go/render"
"github.com/google/uuid"
)
// Types of chunks.
const (
MapType int = iota
GridType
)
// Chunk holds a single portion of the pixel canvas.
type Chunk struct {
Type int // map vs. 2D array.
Accessor
// Values told to it from higher up, not stored in JSON.
Point render.Point
Size int
// Texture cache properties so we don't redraw pixel-by-pixel every frame.
uuid uuid.UUID
bitmap image.Image
texture render.Texturer
textureMasked render.Texturer
textureMaskedColor render.Color
dirty bool
}
// JSONChunk holds a lightweight (interface-free) copy of the Chunk for
// unmarshalling JSON files from disk.
type JSONChunk struct {
Type int `json:"type"`
Data json.RawMessage `json:"data"`
BinData interface{} `json:"-"`
}
// Accessor provides a high-level API to interact with absolute pixel coordinates
// while abstracting away the details of how they're stored.
type Accessor interface {
Inflate(*Palette) error
Iter() <-chan Pixel
IterViewport(viewport render.Rect) <-chan Pixel
Get(render.Point) (*Swatch, error)
Set(render.Point, *Swatch) error
Delete(render.Point) error
Len() int
MarshalJSON() ([]byte, error)
UnmarshalJSON([]byte) error
}
// NewChunk creates a new chunk.
func NewChunk() *Chunk {
return &Chunk{
Type: MapType,
Accessor: NewMapAccessor(),
}
}
// Texture will return a cached texture for the rendering engine for this
// chunk's pixel data. If the cache is dirty it will be rebuilt in this func.
//
// Texture cache can be disabled with balance.DisableChunkTextureCache=true.
func (c *Chunk) Texture(e render.Engine) render.Texturer {
if c.texture == nil || c.dirty {
// Generate the normal bitmap and one with a color mask if applicable.
tex, err := c.generateTexture(render.Invisible)
if err != nil {
log.Error("Texture: %s", err)
}
c.texture = tex
c.textureMasked = nil // invalidate until next call
c.dirty = false
}
return c.texture
}
// TextureMasked returns a cached texture with the ColorMask applied.
func (c *Chunk) TextureMasked(e render.Engine, mask render.Color) render.Texturer {
if c.textureMasked == nil || c.textureMaskedColor != mask {
// Force regenerate with the new mask color.
c.dirty = true
tex, err := c.generateTexture(mask)
if err != nil {
log.Error("Texture: %s", err)
}
c.textureMasked = tex
c.textureMaskedColor = mask
}
return c.textureMasked
}
// SetDirty sets the `dirty` flag to true and forces the texture to be
// re-computed next frame.
func (c *Chunk) SetDirty() {
c.dirty = true
}
// CachedBitmap returns a cached render of the chunk as a bitmap image.
//
// This is like Texture() but skips the step of actually producing an
// (SDL2) texture. The benefit of this is that you can call it from
// your non-main threads and offload the bitmap work into background
// tasks, then when SDL2 needs the Texture, the cached bitmap is
// immediately there saving time on the main thread.
func (c *Chunk) CachedBitmap(mask render.Color) image.Image {
if c.bitmap == nil || c.dirty {
c.bitmap = c.ToBitmap(mask)
}
return c.bitmap
}
// generateTexture takes the chunk's Bitmap, turns it into an (SDL2)
// texture, and caches the texture in memory until the chunk is marked
// as dirty.
func (c *Chunk) generateTexture(mask render.Color) (render.Texturer, error) {
// Generate a unique name for this chunk cache.
var name string
if c.uuid == uuid.Nil {
c.uuid = uuid.Must(uuid.NewUUID())
}
name = c.uuid.String()
if mask != render.Invisible {
name += fmt.Sprintf("-%02x%02x%02x%02x",
mask.Red, mask.Green, mask.Blue, mask.Alpha,
)
}
// Get (and/or cache) the chunk to a bitmap image.
// Note: the 1st call to Bitmap or after SetDirty will
// generate the image and store it cached.
bitmap := c.CachedBitmap(mask)
// Cache the texture data with the current renderer.
tex, err := shmem.CurrentRenderEngine.StoreTexture(name, bitmap)
return tex, err
}
// ToBitmap exports the chunk's pixels as a bitmap image.
// NOT CACHED! This will always run the logic. Use Bitmap() if you
// want a cached bitmap image that only generates itself once, and
// again when marked dirty.
func (c *Chunk) ToBitmap(mask render.Color) image.Image {
canvas := c.SizePositive()
imgSize := image.Rectangle{
Min: image.Point{},
Max: image.Point{
X: c.Size,
Y: c.Size,
},
}
if imgSize.Max.X == 0 {
imgSize.Max.X = int(canvas.W)
}
if imgSize.Max.Y == 0 {
imgSize.Max.Y = int(canvas.H)
}
img := image.NewRGBA(imgSize)
// Blank out the pixels.
// TODO PERF: may be slow?
for x := 0; x < img.Bounds().Max.X; x++ {
for y := 0; y < img.Bounds().Max.Y; y++ {
img.Set(x, y, balance.DebugChunkBitmapBackground.ToColor())
}
}
// Pixel coordinate offset to map the Chunk World Position to the
// smaller image boundaries.
pointOffset := render.Point{
X: c.Point.X * c.Size,
Y: c.Point.Y * c.Size,
}
// Blot all the pixels onto it.
for px := range c.Iter() {
var color = px.Swatch.Color
// If the swatch has a pattern, mesh it in.
if px.Swatch.Pattern != "" {
color = pattern.SampleColor(px.Swatch.Pattern, color, px.Point())
}
if mask != render.Invisible {
// A semi-transparent mask will overlay on top of the actual color.
if mask.Alpha < 255 {
color = color.AddColor(mask)
} else {
color = mask
}
}
img.Set(
px.X-pointOffset.X,
px.Y-pointOffset.Y,
color.ToColor(),
)
}
return img
}
// Set proxies to the accessor and flags the texture as dirty.
func (c *Chunk) Set(p render.Point, sw *Swatch) error {
c.dirty = true
return c.Accessor.Set(p, sw)
}
// Delete proxies to the accessor and flags the texture as dirty.
func (c *Chunk) Delete(p render.Point) error {
c.dirty = true
return c.Accessor.Delete(p)
}
// Rect returns the bounding coordinates that the Chunk has pixels for.
func (c *Chunk) Rect() render.Rect {
// Lowest and highest chunks.
var (
lowest render.Point
highest render.Point
)
for coord := range c.Iter() {
if coord.X < lowest.X {
lowest.X = coord.X
}
if coord.Y < lowest.Y {
lowest.Y = coord.Y
}
if coord.X > highest.X {
highest.X = coord.X
}
if coord.Y > highest.Y {
highest.Y = coord.Y
}
}
return render.Rect{
X: lowest.X,
Y: lowest.Y,
W: highest.X,
H: highest.Y,
}
}
// SizePositive returns the Size anchored to 0,0 with only positive
// coordinates.
func (c *Chunk) SizePositive() render.Rect {
S := c.Rect()
return render.Rect{
W: int(math.Abs(float64(S.X))) + S.W,
H: int(math.Abs(float64(S.Y))) + S.H,
}
}
// Usage returns the percent of free space vs. allocated pixels in the chunk.
func (c *Chunk) Usage(size int) float64 {
return float64(c.Len()) / float64(size)
}
// MarshalJSON writes the chunk to JSON.
func (c *Chunk) MarshalJSON() ([]byte, error) {
data, err := c.Accessor.MarshalJSON()
if err != nil {
return []byte{}, err
}
generic := &JSONChunk{
Type: c.Type,
Data: data,
}
b, err := json.Marshal(generic)
return b, err
}
// UnmarshalJSON loads the chunk from JSON and uses the correct accessor to
// parse the inner details.
func (c *Chunk) UnmarshalJSON(b []byte) error {
// Parse it generically so we can hand off the inner "data" object to the
// right accessor for unmarshalling.
generic := &JSONChunk{}
err := json.Unmarshal(b, generic)
if err != nil {
return fmt.Errorf("Chunk.UnmarshalJSON: failed to unmarshal into generic JSONChunk type: %s", err)
}
switch c.Type {
case MapType:
c.Accessor = NewMapAccessor()
return c.Accessor.UnmarshalJSON(generic.Data)
default:
return fmt.Errorf("Chunk.UnmarshalJSON: unsupported chunk type '%d'", c.Type)
}
}