Add dynamic and static text examples.

boxy.nimble

@@ -6,7 +6,7 @@ license     = "MIT"
 srcDir = "src"
 
 requires "nim >= 1.2.2"
-requires "pixie >= 3.0.0"
+requires "pixie >= 4.1.0"
 requires "vmath >= 1.1.0"
 requires "opengl >= 1.2.3"
 requires "bitty >= 0.1.4"

examples/text_dynamic.nim

@@ -0,0 +1,75 @@
+import boxy, opengl, windy, times
+
+let windowSize = ivec2(1280, 800)
+
+let window = newWindow("Windy + Boxy", windowSize)
+makeContextCurrent(window)
+
+loadExtensions()
+
+let bxy = newBoxy()
+
+# Load the images.
+bxy.addImage("bg", readImage("examples/data/bg.png"))
+
+var frame: int
+
+let typeface = readTypeface("examples/data/IBMPlexMono-Bold.ttf")
+
+proc drawText(
+  bxy: Boxy,
+  imageKey: string,
+  transform: Mat3,
+  typeface: Typeface,
+  text: string,
+  size: float32,
+  color: Color
+) =
+  var font = newFont(typeface)
+  font.size = size
+  font.paint = color
+  let
+    arrangement = typeset(@[newSpan(text, font)], bounds = vec2(1280, 800))
+    globalBounds = arrangement.computeBounds(transform).snapToPixels()
+    textImage = newImage(globalBounds.w.int, globalBounds.h.int)
+    imageSpace = translate(-globalBounds.xy) * transform
+  textImage.fillText(arrangement, imageSpace)
+
+  bxy.addImage(imageKey, textImage)
+  bxy.drawImage(imageKey, globalBounds.xy)
+
+# Called when it is time to draw a new frame.
+proc display() =
+  # Clear the screen and begin a new frame.
+  bxy.beginFrame(windowSize)
+
+  # Draw the bg.
+  bxy.drawImage("bg", rect = rect(vec2(0, 0), windowSize.vec2))
+
+  bxy.drawText(
+    "main-image",
+    translate(vec2(100, 100)),
+    typeface,
+    "Current time:",
+    80,
+    color(1, 1, 1, 1)
+  )
+
+  bxy.drawText(
+    "main-image2",
+    translate(vec2(100, 200)),
+    typeface,
+    now().format("hh:mm:ss"),
+    80,
+    color(1, 1, 1, 1)
+  )
+
+  # End this frame, flushing the draw commands.
+  bxy.endFrame()
+  # Swap buffers displaying the new Boxy frame.
+  window.swapBuffers()
+  inc frame
+
+while not window.closeRequested:
+  display()
+  pollEvents()

examples/text_static.nim

@@ -0,0 +1,67 @@
+import boxy, opengl, windy
+
+let windowSize = ivec2(1280, 800)
+
+let window = newWindow("Windy + Boxy", windowSize)
+makeContextCurrent(window)
+
+loadExtensions()
+
+let bxy = newBoxy()
+
+# Load the images.
+bxy.addImage("bg", readImage("examples/data/bg.png"))
+
+var frame: int
+
+let
+  typeface1 = readTypeface("examples/data/PinyonScript.ttf")
+  font1 = newFont(typeface1)
+font1.size = 40
+font1.paint = "#FFFFFF"
+
+let poem = """
+Once upon a midnight dreary, while I pondered, weak and weary,
+Over many a quaint and curious volume of forgotten lore—
+    While I nodded, nearly napping, suddenly there came a tapping,
+As of some one gently rapping, rapping at my chamber door.
+“’Tis some visitor,” I muttered, “tapping at my chamber door—
+            Only this and nothing more.”
+
+    Ah, distinctly I remember it was in the bleak December;
+And each separate dying ember wrought its ghost upon the floor.
+    Eagerly I wished the morrow;—vainly I had sought to borrow
+    From my books surcease of sorrow—sorrow for the lost Lenore—
+For the rare and radiant maiden whom the angels name Lenore—
+            Nameless here for evermore.
+"""
+
+let
+  arrangement = typeset(@[newSpan(poem, font1)], bounds = vec2(1280, 800))
+  snappedBounds = arrangement.computeBounds().snapToPixels()
+  textImage = newImage(snappedBounds.w.int, snappedBounds.h.int)
+
+textImage.fillText(arrangement, translate(-snappedBounds.xy))
+
+bxy.addImage("text", textImage)
+
+# Called when it is time to draw a new frame.
+proc display() =
+  # Clear the screen and begin a new frame.
+  bxy.beginFrame(windowSize)
+
+  # Draw the bg.
+  bxy.drawImage("bg", rect = rect(vec2(0, 0), windowSize.vec2))
+
+  # Draw big static text:
+  bxy.drawImage("text", snappedBounds.xy + vec2(100, 100))
+
+  # End this frame, flushing the draw commands.
+  bxy.endFrame()
+  # Swap buffers displaying the new Boxy frame.
+  window.swapBuffers()
+  inc frame
+
+while not window.closeRequested:
+  display()
+  pollEvents()

src/boxy.nim

@@ -1,5 +1,5 @@
 import bitty, boxy/buffers, boxy/shaders, boxy/textures, bumpy, chroma, hashes,
-    opengl, os, pixie, strutils, tables, vmath
+    opengl, os, pixie, strutils, tables, vmath, sets
 
 export pixie
 
@@ -37,6 +37,7 @@ type
     mat: Mat4                  ## The current matrix.
     mats: seq[Mat4]            ## The matrix stack.
     entries: Table[string, ImageInfo]
+    entriesBuffered: HashSet[string] ## Entires used by not flushed yet.
     tileSize: int
     maxTiles: int
     tileRun: int
@@ -94,7 +95,7 @@ proc draw(boxy: Boxy) =
   ## Flips - draws current buffer and starts a new one.
   if boxy.quadCount == 0:
     return
-
+  boxy.entriesBuffered.clear()
   boxy.upload()
 
   glUseProgram(boxy.activeShader.programId)
@@ -352,6 +353,13 @@ proc takeFreeTile(boxy: Boxy): int =
 
 proc removeImage*(boxy: Boxy, key: string) =
   ## Removes an image, does nothing if the image has not been added.
+
+  if key in boxy.entriesBuffered:
+    raise newException(
+      BoxyError,
+      "Attempting to remove an image that is set to be drawn"
+    )
+
   if key in boxy.entries:
     for tileLevel in boxy.entries[key].tiles:
       for tile in tileLevel:
@@ -360,8 +368,17 @@ proc removeImage*(boxy: Boxy, key: string) =
     boxy.entries.del(key)
 
 proc addImage*(boxy: Boxy, key: string, image: Image, genMipmaps = true) =
+
+  if key in boxy.entriesBuffered:
+    raise newException(
+      BoxyError,
+      "Attempting to modify an image that is already set to be drawn " &
+      "(try using a unique key?)"
+    )
   boxy.removeImage(key)
 
+  boxy.entriesBuffered.incl(key)
+
   var imageInfo: ImageInfo
   imageInfo.size = ivec2(image.width.int32, image.height.int32)