Support custom transformations for the abstract driver. (#100)

.gitignore

@@ -1,3 +1,5 @@
+/build/
+out/
+.packages/
 *.swp
 *.swo
-.packages

Makefile

@@ -6,24 +6,28 @@ all: test
 
 .PHONY: build/host/CMakeCache.txt
 build/CMakeCache.txt:
-	$(MAKE) rebuild-cmake
+	@$(MAKE) rebuild-cmake
 
 .PHONY: install-pkgs
 install-pkgs: rebuild-cmake
-	(cd build && ninja install-pkgs)
-	(cd tests/toit-png-tools && $(MAKE) rebuild-cmake)
-	(cd tests/toit-png-tools && cmake -DTOITRUN:FILEPATH="$${TOITRUN:-toit.run}" -DTOITPKG:FILEPATH="$${TOITPKG:-toit.pkg}" build)
-	(cd tests/toit-png-tools && $(MAKE) install-pkgs)
+	@(cd build && ninja install-pkgs)
+	@[ -f tests/toit-png-tools/Makefile ] || \
+		(echo "The 'tests/toit-png-tools/' directory doesn't contain a makefile." && \
+		 echo "Run 'git submodule update --init' to get the submodule." && \
+		 exit 1)
+	@(cd tests/toit-png-tools && $(MAKE) rebuild-cmake)
+	@(cd tests/toit-png-tools && cmake -DTOITRUN:FILEPATH="$${TOITRUN:-toit.run}" -DTOITPKG:FILEPATH="$${TOITPKG:-toit.pkg}" build)
+	@(cd tests/toit-png-tools && $(MAKE) install-pkgs)
 
 test: install-pkgs rebuild-cmake
-	(cd build && ninja check)
+	@(cd build && ninja check)
 
 # We rebuild the cmake file all the time.
 # We use "glob" in the cmakefile, and wouldn't otherwise notice if a new
 # file (for example a test) was added or removed.
 # It takes <1s on Linux to run cmake, so it doesn't hurt to run it frequently.
 rebuild-cmake:
-	mkdir -p build
-	(cd build && cmake .. -G Ninja)
+	@mkdir -p build
+	@(cd build && cmake .. -G Ninja)
 
 .PHONY: all test rebuild-cmake install-pkgs

package.lock

@@ -1,4 +1,4 @@
-sdk: ^2.0.0-alpha.121
+sdk: ^2.0.0-alpha.144
 prefixes:
   png-tools: toit-png-tools
 packages:

src/pixel-display-impl_.toit

@@ -34,9 +34,9 @@ FLAG-PARTIAL-UPDATES ::= 0b1000000
 /**
 Abstract superclass for all pixel display drivers.
 For example, implemented by the drivers in
-  https://pkg.toit.io/package/color_tft&url=github.com%2Ftoitware%2Ftoit-color-tft&index=latest
+  https://pkg.toit.io/package/github.com%2Ftoitware%2Ftoit-color-tft
   and
-  https://pkg.toit.io/package/ssd1306&url=github.com%2Ftoitware%2Ftoit-ssd1306&index=latest
+  https://pkg.toit.io/package/github.com%2Ftoitware%2Ftoit-ssd1306
 */
 abstract class AbstractDriver:
   abstract width -> int
@@ -60,6 +60,31 @@ abstract class AbstractDriver:
     throw "Not a true-color driver"
   close -> none:
 
+  /**
+  The transform that should be used depending on whether $inverted and $portrait is set.
+
+  If the parameter $portrait is set to null the driver is free to choose its default orientation.
+  */
+  base-transform --inverted/bool --portrait/bool? -> Transform:
+    transform_/Transform := ?
+    rotation := 0
+    if portrait != null:
+      if portrait == (width < height):
+        rotation = inverted ? 180 : 0
+      else:
+        rotation = inverted ? 270 : 90
+    else if inverted:
+      rotation = 180
+    if rotation == 0:
+      transform_ = Transform.identity
+    else if rotation == 90:
+      transform_ = (Transform.identity.translate 0 height).rotate-left
+    else if rotation == 180:
+      transform_ = (Transform.identity.translate width height).rotate-left.rotate-left
+    else:
+      transform_ = (Transform.identity.translate width 0).rotate-right
+    return transform_
+
 /**
 Common code for pixel-based displays connected to devices.
 Height and width must be multiples of 8.
@@ -219,26 +244,9 @@ abstract class PixelDisplay implements Window:
       dirty-strips := (height >> 6) + 1  // 8-tall strips of dirty bits.
       dirty_ = ByteArray dirty-bytes-per-line_ * dirty-strips
 
+    transform_ = driver_.base-transform --inverted=inverted --portrait=portrait
     if transform:
-      if portrait != null or inverted: throw "INVALID_ARGUMENT"
-      transform_ = transform
-    else:
-      rotation := 0
-      if portrait != null:
-        if portrait == (driver_.width < driver_.height):
-          rotation = inverted ? 180 : 0
-        else:
-          rotation = inverted ? 270 : 90
-      else if inverted:
-        rotation = 180
-      if rotation == 0:
-        transform_ = Transform.identity
-      else if rotation == 90:
-        transform_ = (Transform.identity.translate 0 driver_.height).rotate-left
-      else if rotation == 180:
-        transform_ = (Transform.identity.translate driver_.width driver_.height).rotate-left.rotate-left
-      else:
-        transform_ = (Transform.identity.translate driver_.width 0).rotate-right
+      transform_ = transform_.apply transform
 
     if driver_.flags & FLAG-PARTIAL-UPDATES != 0:
       all-is-dirty_
@@ -1032,7 +1040,7 @@ abstract class Canvas:
       --source-width/int
       --orientation/int=ORIENTATION-0
       --source-line-stride/int=source-width:
-   throw "Unimplemented"
+    throw "Unimplemented"
 
   /**
   Draws the given 24-bit pixmap on the canvas.
@@ -1053,10 +1061,10 @@ abstract class Canvas:
       --orientation/int=ORIENTATION-0:
     throw "UNSUPPORTED"  // Only on true color canvas.
 
-TRANSFORM-IDENTITY_ ::= Transform.with_ --x1=1 --x2=0 --y1=0 --y2=1 --tx=0 --ty=0
-TRANSFORM-90_ ::= Transform.with_ --x1=0 --x2=-1 --y1=1 --y2=0 --tx=0 --ty=0
-TRANSFORM-180_ ::= Transform.with_ --x1=-1 --x2=0 --y1=0 --y2=-1 --tx=0 --ty=0
-TRANSFORM-270_ ::= Transform.with_ --x1=0 --x2=1 --y1=-1 --y2=0 --tx=0 --ty=0
+TRANSFORM-IDENTITY_ ::= Transform --x1=1 --x2=0 --y1=0 --y2=1 --tx=0 --ty=0
+TRANSFORM-90_ ::= Transform --x1=0 --x2=-1 --y1=1 --y2=0 --tx=0 --ty=0
+TRANSFORM-180_ ::= Transform --x1=-1 --x2=0 --y1=0 --y2=-1 --tx=0 --ty=0
+TRANSFORM-270_ ::= Transform --x1=0 --x2=1 --y1=-1 --y2=0 --tx=0 --ty=0
 
 /**
 Classic 3x3 matrix for 2D transformations.
@@ -1077,14 +1085,21 @@ class Transform:
   constructor.identity:
     return TRANSFORM-IDENTITY_
 
-  constructor.with_ --x1/int --y1/int --x2/int --y2/int --tx/int --ty/int:
+  constructor --x1/int --y1/int --x2/int --y2/int --tx/int --ty/int:
+    if x1 * y2 - y1 * x2 != 1:
+      throw "Unsupported scaling"
     x1_ = x1
     x2_ = x2
     tx_ = tx
     y1_ = y1
     y2_ = y2
     ty_ = ty
 
+  constructor.with_ --x1/int --y1/int --x2/int --y2/int --tx/int --ty/int:
+    if x1 == 1 and y1 == 0 and x2 == 0 and y2 == 1 and tx == 0 and ty == 0:
+      return TRANSFORM-IDENTITY_
+    return Transform --x1=x1 --y1=y1 --x2=x2 --y2=y2 --tx=tx --ty=ty
+
   /**
   Applies the other transform to this transform.
   Returns a transform that does both transformations in one transform.
@@ -1253,6 +1268,9 @@ class Transform:
   height width/int height/int -> int:
     return width * y1_ + height * y2_
 
+  stringify -> string:
+    return "Transform x1=$x1_ y1=$y1_ x2=$x2_ y2=$y2_ tx=$tx_ ty=$ty_"
+
 class TextExtent_:
   x := 0
   y := 0

src/png.toit

@@ -13,7 +13,7 @@ Element that draws a PNG image.
 The width and height of the element is determined by the image.
 The image is given by a byte array, png-file, which must be a valid PNG file.
 The PNG file can be converted to a Toit byte array using the
-   xxxd tool (https://github.com/toitware/xxxd).
+  xxxd tool (https://github.com/toitware/xxxd).
 The PNG file can be compressed (a normal PNG file) or uncompressed.
   Uncompressed PNG files are produced by pngunzip, which is part of
   the releases of the png-tools package at

tests/CMakeLists.txt

@@ -10,7 +10,6 @@ set(TOITPKG toit.pkg${CMAKE_EXECUTABLE_SUFFIX} CACHE FILEPATH "The executable us
 set(TEST_TIMEOUT 40 CACHE STRING "The maximal amount of time each test is allowed to run")
 set(SLOW_TEST_TIMEOUT 200 CACHE STRING "The maximal amount of time each slow test is allowed to run")
 
-message("TPKG: ${TOITPKG}")
 add_custom_target(
   "install-pkgs"
   COMMAND "${TOITPKG}" install
@@ -29,8 +28,12 @@ add_custom_target(
 set(TEST_PREFIX "")
 include(fail.cmake OPTIONAL)
 
-message("Failing tests: ${FAILING_TESTS}")
-message("Skipped tests: ${SKIP_TESTS}")
+if (FAILING_TESTS)
+  message("Failing tests: ${FAILING_TESTS}")
+endif()
+if (SKIP_TESTS)
+  message("Skipped tests: ${SKIP_TESTS}")
+endif()
 
 foreach(file ${TESTS})
   set(test_name "/tests/${file}")

tests/custom-transform-visualized.toit

@@ -0,0 +1,38 @@
+// Copyright (C) 2024 Toitware ApS.
+// Use of this source code is governed by a Zero-Clause BSD license that can
+// be found in the TESTS_LICENSE file.
+
+import bitmap show *
+import font show Font
+import pixel-display show *
+import pixel-display.two-color show BLACK WHITE
+import .png-visualizer
+
+class TransformedDriver extends TwoColorPngVisualizer:
+  constructor width/int height/int path/string --outline/int?=null:
+    super width height path --outline=outline
+
+  base-transform --inverted/bool --portrait/bool? -> Transform:
+    // Simulate a display that wants its input rotated 90 degrees and inverted.
+    if portrait == null:
+      portrait = true
+    else:
+      portrait = not portrait
+    return super --no-inverted --portrait=portrait
+
+main args:
+  sans10 := Font.get "sans10"
+
+  if args.size != 1:
+    print "Usage: script.toit png-basename"
+    exit 1
+  driver := TransformedDriver 240 160 args[0] --outline=BLACK
+  display := PixelDisplay.two-color driver
+  display.background = WHITE
+
+  text := Label --x=10 --y=55 --text="Hello, World!" --font=sans10 --color=BLACK
+  display.add text
+
+  display.draw
+
+  driver.write-png