doodle/pkg/uix/canvas.go
Noah Petherbridge f8a83cbad9 Detect Collision Between Actors
* Move all collision code into the pkg/collision package.
  * pkg/doodads/collision.go -> pkg/collision/collide_level.go
  * pkg/doodads/collide_actors.go for new Actor collide support
* Add initial collision detection code between actors in Play Mode.
2019-04-15 19:17:25 -07:00

295 lines
8.5 KiB
Go

package uix
import (
"fmt"
"os"
"strings"
"git.kirsle.net/apps/doodle/lib/events"
"git.kirsle.net/apps/doodle/lib/render"
"git.kirsle.net/apps/doodle/lib/ui"
"git.kirsle.net/apps/doodle/pkg/balance"
"git.kirsle.net/apps/doodle/pkg/collision"
"git.kirsle.net/apps/doodle/pkg/doodads"
"git.kirsle.net/apps/doodle/pkg/level"
"git.kirsle.net/apps/doodle/pkg/log"
"git.kirsle.net/apps/doodle/pkg/wallpaper"
)
// Canvas is a custom ui.Widget that manages a single drawing.
type Canvas struct {
ui.Frame
Palette *level.Palette
// Editable and Scrollable go hand in hand and, if you initialize a
// NewCanvas() with editable=true, they are both enabled.
Editable bool // Clicking will edit pixels of this canvas.
Scrollable bool // Cursor keys will scroll the viewport of this canvas.
// Selected draw tool/mode, default Pencil, for editable canvases.
Tool Tool
// MaskColor will force every pixel to render as this color regardless of
// the palette index of that pixel. Otherwise pixels behave the same and
// the palette does work as normal. Set to render.Invisible (zero value)
// to remove the mask.
MaskColor render.Color
// Actor ID to follow the camera on automatically, i.e. the main player.
FollowActor string
// Debug tools
// NoLimitScroll suppresses the scroll limit for bounded levels.
NoLimitScroll bool
// Underlying chunk data for the drawing.
chunks *level.Chunker
// Actors to superimpose on top of the drawing.
actor *Actor // if this canvas IS an actor
actors []*Actor // if this canvas CONTAINS actors (i.e., is a level)
// Wallpaper settings.
wallpaper *Wallpaper
// When the Canvas wants to delete Actors, but ultimately it is upstream
// that controls the actors. Upstream should delete them and then reinstall
// the actor list from scratch.
OnDeleteActors func([]*level.Actor)
OnDragStart func(filename string)
// Tracking pixels while editing. TODO: get rid of pixelHistory?
pixelHistory []*level.Pixel
lastPixel *level.Pixel
// We inherit the ui.Widget which manages the width and height.
Scroll render.Point // Scroll offset for which parts of canvas are visible.
}
// NewCanvas initializes a Canvas widget.
//
// If editable is true, Scrollable is also set to true, which means the arrow
// keys will scroll the canvas viewport which is desirable in Edit Mode.
func NewCanvas(size int, editable bool) *Canvas {
w := &Canvas{
Editable: editable,
Scrollable: editable,
Palette: level.NewPalette(),
chunks: level.NewChunker(size),
actors: make([]*Actor, 0),
wallpaper: &Wallpaper{},
}
w.setup()
w.IDFunc(func() string {
var attrs []string
if w.Editable {
attrs = append(attrs, "editable")
} else {
attrs = append(attrs, "read-only")
}
if w.Scrollable {
attrs = append(attrs, "scrollable")
}
return fmt.Sprintf("Canvas<%d; %s>", size, strings.Join(attrs, "; "))
})
return w
}
// Load initializes the Canvas using an existing Palette and Grid.
func (w *Canvas) Load(p *level.Palette, g *level.Chunker) {
w.Palette = p
w.chunks = g
if len(w.Palette.Swatches) > 0 {
w.SetSwatch(w.Palette.Swatches[0])
}
}
// LoadLevel initializes a Canvas from a Level object.
func (w *Canvas) LoadLevel(e render.Engine, level *level.Level) {
w.Load(level.Palette, level.Chunker)
// TODO: wallpaper paths
filename := "assets/wallpapers/" + level.Wallpaper
if _, err := os.Stat(filename); os.IsNotExist(err) {
log.Error("LoadLevel: %s", err)
filename = "assets/wallpapers/notebook.png" // XXX TODO
}
wp, err := wallpaper.FromFile(e, filename)
if err != nil {
log.Error("wallpaper FromFile(%s): %s", filename, err)
}
w.wallpaper.maxWidth = level.MaxWidth
w.wallpaper.maxHeight = level.MaxHeight
err = w.wallpaper.Load(e, level.PageType, wp)
if err != nil {
log.Error("wallpaper Load: %s", err)
}
}
// LoadDoodad initializes a Canvas from a Doodad object.
func (w *Canvas) LoadDoodad(d *doodads.Doodad) {
// TODO more safe
w.Load(d.Palette, d.Layers[0].Chunker)
}
// SetSwatch changes the currently selected swatch for editing.
func (w *Canvas) SetSwatch(s *level.Swatch) {
w.Palette.ActiveSwatch = s
}
// setup common configs between both initializers of the canvas.
func (w *Canvas) setup() {
// XXX: Debug code.
if balance.DebugCanvasBorder != render.Invisible {
w.Configure(ui.Config{
BorderColor: balance.DebugCanvasBorder,
BorderSize: 2,
BorderStyle: ui.BorderSolid,
})
}
}
// Loop is called on the scene's event loop to handle mouse interaction with
// the canvas, i.e. to edit it.
func (w *Canvas) Loop(ev *events.State) error {
// Process the arrow keys scrolling the level in Edit Mode.
// canvas_scrolling.go
w.loopEditorScroll(ev)
if err := w.loopFollowActor(ev); err != nil {
log.Error("Follow actor: %s", err) // not fatal but nice to know
}
if err := w.loopConstrainScroll(); err != nil {
log.Debug("loopConstrainScroll: %s", err)
}
// Move any actors. As we iterate over all actors, track their bounding
// rectangles so we can later see if any pair of actors intersect each other.
boxes := make([]render.Rect, len(w.actors))
for i, a := range w.actors {
// Get the actor's velocity to see if it's moving this tick.
v := a.Velocity()
// If not moving, grab the bounding box right now.
if v == render.Origin {
boxes[i] = doodads.GetBoundingRect(a)
continue
}
// Create a delta point from their current location to where they
// want to move to this tick.
delta := a.Position()
delta.Add(v)
// Check collision with level geometry.
info, ok := collision.CollidesWithGrid(a, w.chunks, delta)
if ok {
// Collision happened with world.
log.Error("COLLIDE %+v", info)
}
delta = info.MoveTo // Move us back where the collision check put us
// Move the actor's World Position to the new location.
a.MoveTo(delta)
// Keep the actor from leaving the world borders of bounded maps.
w.loopContainActorsInsideLevel(a)
// Store this actor's bounding box after they've moved.
boxes[i] = doodads.GetBoundingRect(a)
}
// Check collisions between actors.
for tuple := range collision.BetweenBoxes(boxes) {
log.Error("Actor %s collides with %s",
w.actors[tuple[0]].ID(),
w.actors[tuple[1]].ID(),
)
}
// If the canvas is editable, only care if it's over our space.
if w.Editable {
cursor := render.NewPoint(ev.CursorX.Now, ev.CursorY.Now)
if cursor.Inside(ui.AbsoluteRect(w)) {
return w.loopEditable(ev)
}
}
return nil
}
// Viewport returns a rect containing the viewable drawing coordinates in this
// canvas. The X,Y values are the scroll offset (top left) and the W,H values
// are the scroll offset plus the width/height of the Canvas widget.
//
// The Viewport rect are the Absolute World Coordinates of the drawing that are
// visible inside the Canvas. The X,Y is the top left World Coordinate and the
// W,H are the bottom right World Coordinate, making this rect an absolute
// slice of the world. For a normal rect with a relative width and height,
// use ViewportRelative().
//
// The rect X,Y are the negative Scroll Value.
// The rect W,H are the Canvas widget size minus the Scroll Value.
func (w *Canvas) Viewport() render.Rect {
var S = w.Size()
return render.Rect{
X: -w.Scroll.X,
Y: -w.Scroll.Y,
W: S.W - w.Scroll.X,
H: S.H - w.Scroll.Y,
}
}
// ViewportRelative returns a relative viewport where the Width and Height
// values are zero-relative: so you can use it with point.Inside(viewport)
// to see if a World Index point should be visible on screen.
//
// The rect X,Y are the negative Scroll Value
// The rect W,H are the Canvas widget size.
func (w *Canvas) ViewportRelative() render.Rect {
var S = w.Size()
return render.Rect{
X: -w.Scroll.X,
Y: -w.Scroll.Y,
W: S.W,
H: S.H,
}
}
// WorldIndexAt returns the World Index that corresponds to a Screen Pixel
// on the screen. If the screen pixel is the mouse coordinate (relative to
// the application window) this will return the World Index of the pixel below
// the mouse cursor.
func (w *Canvas) WorldIndexAt(screenPixel render.Point) render.Point {
var P = ui.AbsolutePosition(w)
return render.Point{
X: screenPixel.X - P.X - w.Scroll.X,
Y: screenPixel.Y - P.Y - w.Scroll.Y,
}
}
// Chunker returns the underlying Chunker object.
func (w *Canvas) Chunker() *level.Chunker {
return w.chunks
}
// ScrollTo sets the viewport scroll position.
func (w *Canvas) ScrollTo(to render.Point) {
w.Scroll.X = to.X
w.Scroll.Y = to.Y
}
// ScrollBy adjusts the viewport scroll position.
func (w *Canvas) ScrollBy(by render.Point) {
w.Scroll.Add(by)
}
// Compute the canvas.
func (w *Canvas) Compute(e render.Engine) {
}