Plotter-Z

A 3D function graph plotting tool designed for early handheld devices such as Windows CE 1.0 - 2.1, Palm OS 3, and CASIO fx-9860 series calculators. This project is still in progress. Feedback and issues are welcome.

Installation

On Windows CE

Copy the .exe matching your CPU architecture to the device via Active Sync or external storage (CF, SD card) and run it.

Note: For newer ARM-based devices (Windows CE 5.0, Windows Mobile), use PlotterZ_hpc211_armdbg.exe.

On Palm OS

Install the .prc file via HotSync and run it.

Note: MathLib is required. Download and install it from palmdb.net/app/mathlib before running Plotter-Z.

On CASIO fx-9860G Series

Connect the calculator to your PC via USB and use FA-124 to transfer the .g1a file, or copy it directly through Windows Explorer, or via an SD card to the calculator's storage.

Supported Functions

The following mathematical functions can be used in expressions:

Function	Description	Parameters
sin(x)	Sine	1
cos(x)	Cosine	1
tan(x)	Tangent	1
asin(x)	Arcsine	1
acos(x)	Arccosine	1
atan(x)	Arctangent	1
sqr(x)	Square root	1
exp(x)	Exponential (e^x)	1
abs(x)	Absolute value	1
ln(x)	Natural logarithm	1

Usage

Windows CE

1. File > Samples to pick a preset sample expression.
2. Edit > Expression to enter your own expression.
3. Edit > Window to adjust the plot range (X/Y/Z bounds and grid resolution).
4. View to switch between interaction modes: camera rotation, pan move, zoom, and formula positioning.
5. View > Reset to restore the default camera angles and viewport.
6. File > Save Session / Load Session to persist or restore your current expression and window settings.

You can also toggle a footer status bar (View > Toggle Footer) showing the current camera angles, mode, and zoom level, and toggle the bounding box (View > Toggle Boundary Box).

Palm OS

• Main screen:

  1. Enter an expression and tap Parse. If there are no errors the app renders the mathematical formula.
  2. Options > Window Editor to set the X/Y/Z plot ranges and grid resolution.
  3. Options > Samples to choose from preset sample expressions.
  4. Tap Draw to enter the 3D drawing view.

• Drawing view:

  1. The four corners of the screen are interactive buttons:
     • Top-left — return to the main screen.
     • Top-right — cycle through interaction modes (C = Camera rotate, P = Pan move, Z = Zoom).
     • Bottom-left — toggle the bounding box (b/B).
     • Bottom-right — reset camera angles, viewport, and zoom level.
  2. Drag on the canvas to interact (rotate / pan / zoom depending on the current mode).

CASIO fx-9860G Series

• Main Screen:

  Key	Action
  F1	Edit expression
  F2	Window Editor (set X/Y/Z ranges and grid)
  F3	Browse sample expressions
  F4	Help screen
  F6	Enter Graph Screen (recalc and plot)
  Arrow keys	Move formula position

• Graph Screen:

  Key	Action
  F1	Return to Main Screen
  F3	Animate: increment variable t by 1 and recalculate
  F4	Reset Camera
  F5	Toggle bounding box
  F6	Toggle bottom menu
  Arrow keys	Rotate camera
  2 / 4 / 6 / 8	Pan (translate viewport)
  + / -	Zoom in / out

• Animation: Insert the variable t into your expression to create animated surfaces. Each time you press F3 in the Graph Screen, t increments by 1 and the surface is recalculated, creating a frame-by-frame animation effect.

Troubleshooting on Windows CE

If the program fails with FAILED: DIB SECTION, some devices (tested on CASIO E-100 and iPAQ H3600) have trouble creating a 16-bit DIB section.

Create a file named plotter-z.ini in the root directory of your CE device with the following content to force 8 bpp mode:

[graphics]
force_bpp=8

How It Works

The project is divided into several modules:

Directory	Purpose
formula-z	String expression parser
evaluator-z	Micro VM for numerical evaluation
renderer-z	AST to render tree conversion
plotter-z	Platform-specific app frontends

Formula-Z

This module takes a string input, checks for syntax errors, and converts the string into an AST (Abstract Syntax Tree). Run tests with make fz-test:

./fz-test.exe -h "sin(sqr(x^2+y^2))"

Output:

<Function name="sin">
  <Parameter>
    <Function name="sqr">
      <Parameter>
        <Binary operator="ADD">
          <Binary operator="POW">
            <Variable> x </Variable>
            <Literal> 2 </Literal>
          </Binary>
          <Binary operator="POW">
            <Variable> y </Variable>
            <Literal> 2 </Literal>
          </Binary>
        </Binary>
      </Parameter>
    </Function>
  </Parameter>
</Function>

Evaluator-Z

This module takes the AST generated by formula-z, checks for semantic errors, and compiles it into instructions for a micro virtual machine. Run tests with make ez-test:

# -v declares variables x, y and sets them to 1 and 2
# -l lists compiled instructions
# -e specifies the expression
./ez-test.exe   \
    -v x 1      \
    -v y 2      \
    -l          \
    -e "sin(sqr(x^2+y^2))"

Output:

PUSH_VAR    0
PUSH_IMD    2
POW
PUSH_VAR    1
PUSH_IMD    2
POW
ADD
FUNC        sqr
FUNC        sin
Result = 0.786749

Renderer-Z

This module takes the AST generated by formula-z and converts it into a render tree. Run tests with make rz-test:

./rz-test.exe -h "sin(sqr(x^2+y^2))"

Output:

<Horizontal>
  <Text> sin </Text>
  <Enclosure>
    <Root>
      <Horizontal>
        <Superscript>
          <Body>
            <Text> x </Text>
          </Body>
          <Script>
            <Text> 2 </Text>
          </Script>
        </Superscript>
        <Text> + </Text>
        <Superscript>
          <Body>
            <Text> y </Text>
          </Body>
          <Script>
            <Text> 2 </Text>
          </Script>
        </Superscript>
      </Horizontal>
    </Root>
  </Enclosure>
</Horizontal>

Plotter-Z

This module contains platform-specific implementations of the plotter-z app.

Directory	Purpose
sdl	Proof-of-concept app using SDL
win32-classic	Test only, deprecated
win32-native	Win32 API app for Windows CE / Desktop
palm	Palm OS version
fx	CASIO fx-9860 version

Building

The project favours an out-of-the-box approach, just use each platform's official SDK and toolchain with zero extra configuration.

1. Clone Dependencies

This project depends on two small libraries:

• salvia89 — a compact sprintf replacement. Required because Windows CE 1.0 / 2.0 do not provide sprintf, and their wsprintf lacks important features.
• pine89 — a lightweight INI file parser.

Run the fetch-deps.sh script to clone them:

cd project-path
./fetch-deps.sh

If you cannot run a shell script or don't have Git, you can clone the repositories manually, or download their source from GitHub and place them into the deps directory (refer to the script for exact locations).

2. Build Per Platform

sdl

Requires an SDL 1.2 development environment plus GCC and make. Run:

make

win32-native

Requires one of the following:

• CE 1.x: Visual C++ 5.0 + Windows CE Toolkit for Visual C++ 5.0 (needs Windows NT 4)
• CE 2.x / Desktop: Visual C++ 6.0 + Windows CE Toolkit for Visual C++ 6.0

Open the *.dsw workspace file in the corresponding Visual C++ and build.

palm

Requires CodeWarrior IDE for Palm. Open the *.mcp project file and build.

fx

Requires the fx-9860G SDK. Open the *.g1w project file and build.

License

This project is licensed under the MIT License.