~koehr/dig

3c8b2893100707ccd04dbd65d02cd308192bb5b9 — Norman Köhring 1 year, 5 months ago 1b33608 main
debugging highlights
4 files changed, 338 insertions(+), 47 deletions(-)

M src/App.vue
A src/Background.vue
M src/assets/field.css
A src/util/useBackground.ts
M src/App.vue => src/App.vue +6 -19
@@ 138,12 138,14 @@ const move = (thisTick: number): void => {

  // do nothing when paused
  if (paused.value) {
    lastTick = thisTick // reset tick, to avoid huge tickDelta
    // reset tick, to avoid tickDelta and resulting character teleport
    lastTick = thisTick
    return
  }

  const tickDelta = thisTick - lastTick
  lastTimeUpdate += tickDelta

  // update in-game time every 60ms by 0.1
  // then a day needs 10000 updates, and it takes about 10 minutes
  if (lastTimeUpdate > 60) {


@@ 189,23 191,6 @@ const move = (thisTick: number): void => {
  lastTick = thisTick
}

function calcBrightness(level: number, row: number) {
  const barrier = lightBarrier.value[row]
  const barrierLeft = lightBarrier.value[row - 1]
  const barrierRight = lightBarrier.value[row + 1]

  let delta = barrier - level - (floorY.value - 3)
  const deltaL = Math.min(3, barrierLeft - level - (floorY.value - 3))
  const deltaR = Math.min(3, barrierRight - level - (floorY.value - 3))

  if (delta > 3) delta = 3
  else if (delta < 0) delta = 0

  if (deltaR > delta || deltaL > delta) delta = Math.max(deltaL, deltaR) - 1

  return `sun-${delta}`
}

function selectTool(item: InventoryItem) {
  inventorySelection.value = item
}


@@ 228,7 213,9 @@ onMounted(() => {
    <div id="blocks" :style="{transform: `translate(${tx}px, ${ty}px)`}">
      <template v-for="(row, y) in rows">
        <div v-for="(block, x) in row"
          :class="['block', block.type]"
          :class="['block', block.type, {
            highlight: x === player.x && y == player.y
          }]"
          @click="interactWith(x, y, block)"
        />
      </template>

A src/Background.vue => src/Background.vue +35 -0
@@ 0,0 1,35 @@
<script setup lang="ts">
import { ref, computed, onMounted, watch } from 'vue'
import useBackground from './util/useBackground'
import { BLOCK_SIZE, STAGE_WIDTH, STAGE_HEIGHT } from './level/def'

export interface Props {
  time: number
  x: number
}

const props = defineProps<Props>()
const canvas = ref<HTMLCanvasElement | null>(null)

const p = Math.PI / -10
const sunY = computed(() => Math.sin(props.time * p))


onMounted(() => {
  const canvasEl = canvas.value
  if (canvasEl === null) return

  const drawBackground = useBackground(
    canvasEl,
    ~~(STAGE_WIDTH * BLOCK_SIZE / 2.0),
    ~~(STAGE_HEIGHT * BLOCK_SIZE / 2.0),
  )

  watch(props, () => drawBackground(props.x, sunY.value), { immediate: true })
})

</script>

<template>
  <canvas ref="canvas" id="background"></canvas>
</template>

M src/assets/field.css => src/assets/field.css +111 -28
@@ 1,6 1,8 @@
.block, #player {
.block,
#player {
  transition: filter .5s linear;
}

.block {
  flex: 0 0 auto;
  width: var(--block-size);


@@ 10,6 12,7 @@
  background-position: center;
  background-repeat: no-repeat;
}

.block::after {
  content: '';
  position: absolute;


@@ 23,40 26,120 @@
  background-size: cover;
}

.block.damage-0::after { background-position-x: 0px; }
.block.damage-1::after { background-position-x: calc(var(--block-size) * -1); }
.block.damage-2::after { background-position-x: calc(var(--block-size) * -2); }
.block.damage-3::after { background-position-x: calc(var(--block-size) * -3); }
.block.damage-4::after { background-position-x: calc(var(--block-size) * -4); }
.block.damage-5::after { background-position-x: calc(var(--block-size) * -5); }
.block.damage-6::after { background-position-x: calc(var(--block-size) * -6); }
.block.damage-0::after {
  background-position-x: 0px;
}

.block.damage-1::after {
  background-position-x: calc(var(--block-size) * -1);
}

.block.damage-2::after {
  background-position-x: calc(var(--block-size) * -2);
}

.block.damage-3::after {
  background-position-x: calc(var(--block-size) * -3);
}

.block.damage-4::after {
  background-position-x: calc(var(--block-size) * -4);
}

.block.damage-5::after {
  background-position-x: calc(var(--block-size) * -5);
}

.block.damage-6::after {
  background-position-x: calc(var(--block-size) * -6);
}

.block.grass {
  background-image: url(/Tiles/dirt_grass.png);
}

.block.treeCrown,
.block.treeLeaves {
  background-image: url(/Tiles/leaves_transparent.png);
}

.block.treeTrunk {
  background-image: url(/Tiles/trunk_mid.png);
}

.block.treeRoot {
  background-image: url(/Tiles/trunk_bottom.png);
}

.block.soil {
  background-image: url(/Tiles/dirt.png);
}

.block.soilGravel {
  background-image: url(/Tiles/gravel_dirt.png);
}

.block.grass   { background-image: url(/Tiles/dirt_grass.png); }
.block.stoneGravel {
  background-image: url(/Tiles/gravel_stone.png);
}

.block.treeCrown, .block.treeLeaves { background-image: url(/Tiles/leaves_transparent.png); }
.block.treeTrunk { background-image: url(/Tiles/trunk_mid.png); }
.block.treeRoot  { background-image: url(/Tiles/trunk_bottom.png); }
.block.stone {
  background-image: url(/Tiles/stone.png);
}

.block.soil        { background-image: url(/Tiles/dirt.png); }
.block.soilGravel  { background-image: url(/Tiles/gravel_dirt.png); }
.block.stoneGravel { background-image: url(/Tiles/gravel_stone.png); }
.block.stone       { background-image: url(/Tiles/stone.png); }
.block.bedrock     { background-image: url(/Tiles/greystone.png); }
.block.cave        { background-color: #000; }
.block.bedrock {
  background-image: url(/Tiles/greystone.png);
}

.block.brickWall   { background-image: url(/Tiles/brick_grey.png); }
.block.cave {
  background-color: #000;
}

#field .block:hover { outline: 1px solid white; z-index: 10; }
.block.brickWall {
  background-image: url(/Tiles/brick_grey.png);
}

.morning0 .block, .morning0 #player {filter: saturate(50%); }
.morning1 .block, .morning1 #player { filter: saturate(100%); }
.morning2 .block, .morning2 #player { filter: saturate(120%); }
#field .block:hover,
#field .block.block.highlight {
  filter: brightness(1.2) grayscale(1.0);
  outline: 1px solid white;
  z-index: 10;
}

.evening0 .block, .evening0 #player { filter: saturate(90%); }
.evening1 .block, .evening1 #player { filter: saturate(70%); }
.evening2 .block, .evening2 #player { filter: saturate(50%); }
.morning0 .block,
.morning0 #player {
  filter: saturate(50%);
}

.night .block, .night #player { filter: saturate(30%); }
.morning1 .block,
.morning1 #player {
  filter: saturate(100%);
}

.morning2 .block,
.morning2 #player {
  filter: saturate(120%);
}

.evening0 .block,
.evening0 #player {
  filter: saturate(90%);
}

.evening1 .block,
.evening1 #player {
  filter: saturate(70%);
}

.evening2 .block,
.evening2 #player {
  filter: saturate(50%);
}

.night .block,
.night #player {
  filter: saturate(30%);
}

#blocks {
  position: absolute;


@@ 76,4 159,4 @@
  height: calc(100% + var(--block-size) * 2);
  mix-blend-mode: multiply;
  pointer-events: none;
}
}
\ No newline at end of file

A src/util/useBackground.ts => src/util/useBackground.ts +186 -0
@@ 0,0 1,186 @@

/**
 * hsl - creates hsl color string from h, s and l values
 * @param h: number - hue
 * @param s: number - saturation
 * @param l: number - lightness
 */
function hsl(h: number, s: number, l: number): string {
  return `hsl(${h}, ${s}%, ${l}%)`
}

/**
 * render godrays
 * @param ctx: CanvasRenderingContext2D - where to draw
 * @param cx: number - x-axis center of the "sun"
 * @param cy: number - y-axis center of the "sun"
 * @param sunY: number - the position (height) of the "sun" in the sky
 * @param r: number [44] - the radius of the "sun"
 * @returns emissionStrength: number - emission intensity blends over the mountains
 */
function renderGodrays(ctx: CanvasRenderingContext2D, cx: number, cy: number, sunY: number, r = 44) {
  const w = ctx.canvas.width
  const h = ctx.canvas.height

  const emissionGradient = ctx.createRadialGradient(cx, cy, 0, cx, cy, r)
  ctx.fillStyle = emissionGradient

  // Now we addColorStops. This needs to be a dark gradient because our
  // godrays effect will basically overlay it on top of itself many many times,
  // so anything lighter will result in lots of white.
  // If you're not space-bound you can add another stop or two, maybe fade out to black,
  // but this actually looks good enough.

  // a black "gradient" means no emission, so we fade to black as transition to night or day
  let emissionStrength = 1.0
  if (sunY > -30) emissionStrength -= Math.max((30 + sunY) / 5, 0.0)
  else if (sunY < -60) emissionStrength += Math.min(1 + (60 + sunY) / 5, 0.0)

  emissionGradient.addColorStop(.1, hsl(30, 50, 3.1 * emissionStrength)) // pixels in radius 0 to 4.4 (44 * .1).
  emissionGradient.addColorStop(.2, hsl(12, 71, 1.4 * emissionStrength)) // pixels in radius 0 to 4.4 (44 * .1).
  // Now paint the gradient all over our godrays canvas.
  ctx.fillRect(0, 0, w, h)
  // And set the fillstyle to black, we'll use it to paint our occlusion (mountains).
  ctx.fillStyle = '#000'

  return emissionStrength
}

/**
 * calculate mountain height
 * Mountains are made by summing up sine waves with varying frequencies and amplitudes
 * The frequencies are prime, to avoid extra repetitions
 */
function calcMountainHeight(pos: number, roughness: number, frequencies = [1721, 947, 547, 233, 73, 31, 7]) {
  return frequencies.reduce((height, freq) => height * roughness - Math.cos(freq * pos), 0)
}

/**
 * render mountains
 * @param ctx: CanvasRenderingContext2D - where to draw
 * @param grCtx: CanvasRenderingContext2D - for drawing mountain shadows on the godray canvas
 * @param frame: number - current frame (position on the x axis)
 * @param sunY: number - position (height) of the "sun" in the sky
 * @param layers: number - amount of mountain layers for parallax effect
 * @param emissionStrength: number - intensity of the godrays
 */
function renderMountains(ctx: CanvasRenderingContext2D, grCtx: CanvasRenderingContext2D, frame: number, sunY: number, layers: number, emissionStrength: number) {
  const w = ctx.canvas.width
  const h = ctx.canvas.height
  const grDiv = w / grCtx.canvas.width

  for (let i = 0; i < layers; i++) {
    // Set the main canvas fillStyle to a shade of green-brown with variable lightness
    // depending on sunY and depth
    ctx.fillStyle = sunY > -60
      ? hsl(5, 23, 33*emissionStrength - i*6*emissionStrength)
      : hsl(220 - i*40, 23, 33-i*6)

    for (let x = w; x--;) {
      // Ok, I don't really remember the details here, basically the (frame+frame*i*i) makes the
      // near mountains move faster than the far ones. We divide by large numbers because our
      // mountains repeat at position 1/7*Math.PI*2 or something like that...
      const pos = (frame * 2 * i**2) / 1000 + x / 2000
      // Make further mountains more jagged, adds a bit of realism and also makes the godrays
      // look nicer.
      const roughness = i / 19 - .5
      // 128 is the middle, i * 25 moves the nearer mountains lower on the screen.
      let y = 128 + i * 25 + calcMountainHeight(pos, roughness) * 45
      // Paint a 1px-wide rectangle from the mountain's top to below the bottom of the canvas.
      ctx.fillRect(x, y, 1, h)
      // Paint the same thing in black on the godrays emission canvas, which is 1/4 the size,
      // and move it one pixel down (otherwise there can be a tiny underlit space between the
      // mountains and the sky).
      grCtx.fillRect(x/grDiv, y/grDiv+1, 1, h)
    }
  }
}

/**
 * render sky
 * @param ctx: CanvasRenderingContext2D - where to draw
 * @param sunY: number - the position (height) of the "sun" in the sky
 */
function renderSky(ctx: CanvasRenderingContext2D, sunY: number) {
  const w = ctx.canvas.width
  const h = ctx.canvas.height

  const skyGradient = ctx.createLinearGradient(0, 0, 0, h)
  const skyHue = 360 + sunY // hue from blue to red, depending on the suns position
  const skySaturation = 100 + sunY // less saturation at day so that the red fades away
  const skyLightness = Math.min(sunY * -1 - 10, 55) // darker at night

  const skyHSLTop = `hsl(220, 70%, ${skyLightness}%)`
  const skyHSLBottom = `hsl(${skyHue}, ${skySaturation}%, ${skyLightness}%)`
  skyGradient.addColorStop(0, skyHSLTop)
  skyGradient.addColorStop(.7, skyHSLBottom)

  ctx.fillStyle = skyGradient
  ctx.fillRect(0, 0, w, h)
}

/**
 * useBackground
 * @param canvasEl: HTMLCanvasElement - the canvas to draw the background on.
 * @param w: number - the (pixel) width of the canvas. The element itself can have a different width.
 * @param h: number - the (pixel) height of the canvas. The element itself can have a different height.
 * @param rayQuality: number [8] - The quality of the sunrays (divides the resolution, so higher value means lower quality)
 * @param mountainLayers: number [4] - How many layers of mountains are used for parallax effect?
 */
export default function useBackground (canvasEl: HTMLCanvasElement, w: number, h: number, rayQuality = 8, mountainLayers = 4) {
  canvasEl.width = w
  canvasEl.height = h

  const grW = w / rayQuality
  const grH = h / rayQuality

  const ctx = canvasEl.getContext('2d')
  if (ctx === null) return // like, how old is your browser?

  const grCanvasEl = document.createElement('canvas')
  const grCtx = grCanvasEl.getContext('2d')
  if (grCtx === null) return // like, how old is your browser?

  grCanvasEl.width = grW
  grCanvasEl.height = grH

  const sunCenterX = grCanvasEl.width / 2
  const sunCenterY = grCanvasEl.height / 2

  /**
   * draw one frame of the background
   * @param frame: number - the position on the x axis, to calculate the paralax background
   * @param sunY: number - the position (height) of the sun in the sky
   */
  return function drawFrame (frame: number, sunY: number) {
    console.log('drawing frame', frame, sunY)
    const emissionStrength = renderGodrays(grCtx, sunCenterX, sunCenterY, sunY)
    renderSky(ctx, sunY)
    renderMountains(ctx, grCtx, frame, sunY, mountainLayers, emissionStrength)

    // The godrays are generated by adding up RGB values, gCt is the bane of all js golfers -
    // globalCompositeOperation. Set it to 'lighter' on both canvases.
    ctx.globalCompositeOperation = grCtx.globalCompositeOperation = 'lighter'
    
    // NOW - let's light this m**f** up! We'll make several passes over our emission canvas,
    // each time adding an enlarged copy of it to itself so at the first pass we get 2 copies, then 4,
    // then 8, then 16 etc... We square our scale factor at each iteration.
    for (let scaleFactor = 1.07; scaleFactor < 5; scaleFactor *= scaleFactor) {
      // The x, y, width and height arguments for drawImage keep the light source in the same
      // spot on the enlarged copy. It basically boils down to multiplying a 2D matrix by itself.
      // There's probably a better way to do this, but I couldn't figure it out.
      // For reference, here's an AS3 version (where BitmapData:draw takes a matrix argument):
      // https://github.com/yonatan/volumetrics/blob/d3849027213e9499742cc4dfd2838c6032f4d9d3/src/org/zozuar/volumetrics/EffectContainer.as#L208-L209
      grCtx.drawImage(
        grCanvasEl,
        (grW - grW * scaleFactor) / 2,
        (grH - grH * scaleFactor) / 2 - sunY * scaleFactor + sunY,
        grW * scaleFactor,
        grH * scaleFactor
      )
    }

    // Draw godrays to output canvas (whose globalCompositeOperation is already set to 'lighter').
    ctx.drawImage(grCanvasEl, 0, 0, w, h);
  }
}