API

Introduction

The main functions of the API are listed here, the features of the work of the environment are described

WOWCube Paradigms

WOWCube executes 8 copies of the byte-code of the script at the same time, providing functions for the interaction of scripts with each other, drawing functions, functions for accessing resources, and other specific functions. Each copy of the script has access to 3 displays. Resource scripts are packed into a package.

Pawn API

Graphic functions

Graphics 2D acceleration (G2D)

WOWCube provides the 2D acceleration interfaces to enhance gaming experience . Basically G2D engine allows to blend up to the 4 image layers at once with a HW acceleration. However there is no limit of layers, they are blended in a cascade. For example, if Pawn script requested 7 layers to be blended then 2 HW blending will occur:

Result of the blending can be saved as an internal G2D resource or flushed immediately on the specified display. Internal G2D resources can be used as an usual bitmap primitive (abi_CMD_BITMAP) or reused as an input for the next G2D action. Basic coordinate principle:

Coordinates are limited from -2048 to 2047. Maximum layers size is 240x240.

abi_CMD_G2D_BEGIN_BITMAP

Syntax:

abi_CMD_G2D_BEGIN_BITMAP(const resID, const width, const height, const bool:replace)

Description:

abi_CMD_G2D_BEGIN_BITMAP and abi_CMD_G2D_END delimits the group of layers to be blended into internal G2D resource. This API is not intended for frequent usage. It is better suited for complex background generation on game initialization or dynamic resource modification triggered by rare game events.

Arguments:

resID

ID of the resource that will be generated from blending layers presented between abi_CMD_G2D_BEGIN_BITMAP and the subsequent abi_CMD_G2D_END. G2D engine can keep up to 3 different resources with IDs: 0, 1 and 2.

width

Width of the resulting resource. G2D engine can keep resource of 240px width maximum.

height

Height of the resulting resource. G2D engine can keep resource of 240px height maximum.

replace

If true, then an existing image will be replaced completely, otherwise it will be overwritten by reusing itself as a background layer.

abi_CMD_G2D_BEGIN_DISPLAY

Syntax:

abi_CMD_G2D_BEGIN_DISPLAY(const display, const bool:replace)

Description:

abi_CMD_G2D_BEGIN_DISPLAY and abi_CMD_G2D_END delimits the group of layers to be blended directly into display framebuffer. Obviously this API is designed for rendering scene on game tick. This API is not limited by layers count as well as abi_CMD_G2D_BEGIN_BITMAP. However it is strictly recommended to blend no more than 4 layers. Otherwise cascade blending will be initiated resulting in some FPS drop.

Arguments:

display

ID of the display which framebuffer will be used for blending. Each module have 3 displays with ID starting from 0.

replace

If true then an existing image will be replaced completely, otherwise it will be overwritten by reusing itself as a background layer.

abi_CMD_G2D_ADD_SPRITE

Syntax:

abi_CMD_G2D_ADD_SPRITE(const resID, const bool:g2d, const x, const y, const alpha, const color, const rotation, const mirror)

Description:

Specifies game resource which will be used as a layer for blending.

Arguments:

resID

ID of the resource to be uses as a layer.

g2d

Indicates if an internal G2D resource is specified or not.

x, y

Coordinates of the bitmap center to place on the layer.

alpha

Layer transparency in range between 0x00 and 0xFF, where 0x00 is a fully transparent layer.

color

Layer's source key - a color in ARGB8888 format to be avoided.

rotation

Clockwise rotation angle in degrees. It is possible to specify free angle, but only right angles have HW acceleration. Currently rotation only applicable for external resources.

mirror

Mirroring variant. Possible values are self-explained: MIRROR_BLANK, MIRROR_X, MIRROR_Y, MIRROR_XY.

abi_CMD_G2D_ADD_RECTANGLE

Syntax:

abi_CMD_G2D_ADD_RECTANGLE(const x, const y, const width, const height, const color)

Description:

Specifies rectangle area which will be used as layer of blending. This API is not intended for frequent usage, i.e. particles generation. It is better suited for changing image background or applying color mask.

Arguments:

x, y

Coordinates of top left rectangle corner.

width

Rectangle width.

height

Rectangle height.

color

Rectangle color in ARGB8888 format.

abi_CMD_G2D_END

Syntax:

abi_CMD_G2D_END()

Description:

abi_CMD_G2D_END() and abi_CMD_G2D_BEGIN_BITMAP/abi_CMD_G2D_BEGIN_DISPLAY delimits the group of layers to be blended. After abi_CMD_G2D_END call final blending will be initiated and results will be stored according to the begin comand.

Examples

1. Render into inner G2D resource buffer #face and display it on the display #face. Please, note that last argument of abi_CMD_BITMAP is a `true` flag, which means G2D resource should be used:

...
abi_CMD_G2D_BEGIN_BITMAP(face, 240, 240, true);
abi_CMD_G2D_ADD_RECTANGLE(120 - animationSquareSize0, 120 - animationSquareSize0, animationSquareSize0 * 2, animationSquareSize0 * 2, 0xdfff0000);
abi_CMD_G2D_ADD_RECTANGLE(120 - animationSquareSize1, 120 - animationSquareSize1, animationSquareSize1 * 2, animationSquareSize1 * 2, 0xdfffff00);
abi_CMD_G2D_ADD_RECTANGLE(120 - animationSquareSize2, 120 - animationSquareSize2, animationSquareSize2 * 2, animationSquareSize2 * 2, 0xdfff00ff);
abi_CMD_G2D_ADD_RECTANGLE(120 - animationSquareSize3, 120 - animationSquareSize3, animationSquareSize3 * 2, animationSquareSize3 * 2, 0xdf00ffff);
abi_CMD_G2D_ADD_SPRITE(resID, false, 120, 120, animationAlpha, 0x00000000, animationAngle, MIRROR_BLANK);
abi_CMD_G2D_END();
...
abi_CMD_BITMAP(face, 120, 120, 0, MIRROR_BLANK, true);
...
abi_CMD_REDRAW(face);
...

2. Render directly into display framebuffer #face. This will produce same result on display as example #1, but the generated image is not saved:

...
abi_CMD_G2D_BEGIN_DISPLAY(face, true);
abi_CMD_G2D_ADD_RECTANGLE(120 - animationSquareSize0, 120 - animationSquareSize0, animationSquareSize0 * 2, animationSquareSize0 * 2, 0xdfff0000);
abi_CMD_G2D_ADD_RECTANGLE(120 - animationSquareSize1, 120 - animationSquareSize1, animationSquareSize1 * 2, animationSquareSize1 * 2, 0xdfffff00);
abi_CMD_G2D_ADD_RECTANGLE(120 - animationSquareSize2, 120 - animationSquareSize2, animationSquareSize2 * 2, animationSquareSize2 * 2, 0xdfff00ff);
abi_CMD_G2D_ADD_RECTANGLE(120 - animationSquareSize3, 120 - animationSquareSize3, animationSquareSize3 * 2, animationSquareSize3 * 2, 0xdf00ffff);
abi_CMD_G2D_ADD_SPRITE(resID, false, 120, 120, animationAlpha, 0x00000000, animationAngle, MIRROR_BLANK);
abi_CMD_G2D_END();
...

Font drawing functions

abi_CMD_TEXT

API:

 abi_CMD_TEXT(const text[], const fontResID, const x, const y, const scale, const angle, const r, const g, const b)

Description:

Intended to render a system font or a custom font from resources with specified coordinates, scale and rotation at an arbitrary angle.

Arguments:

text

Array of chars.

fontResID

Custom font resource identifier. Provide -1 to use system font resource.

x, y

Coordinates of top left rectangle corner.

scale, angle

Percentage scale and clockwise rotation angle in degrees. Max size of font is 200x200 px. (scale = 100%)

r, g, b

Font color in RGB format.

Example:

new text[4] = ['A', 'p', 'p', '\0'];
abi_CMD_TEXT(text, RES_ID_FONT, 90, 160, 16, current_angles[face], 255, 0, 0);

TEXTURE drawing functions

abi_CMD_DYNAMIC_TEXTURE

API:

abi_CMD_DYNAMIC_TEXTURE(const effectId = 1, const time = any value, const args[] = {0x04030201, 0x08070605, 0x00000A09}, const argsCount = 3, const bool:g2d = false)

Description:

Render a texture with chosen algorithm and parameters.

Arguments:

effectId

Define algorithm to render texture.

Available values : G2D_DYNAMIC_TEXTURE_MOSAIC

time

Current time value. Use any fixed value to static texture or set current time value in milliseconds to make texture alive.

args, argsCount

Byte stream of algorithm settings it's aligned to 4 bytes, because of pawn supports only 32-bit values.

Size of array depends on algorithm. For example mosaic algorithm has size of settings equals 10 bytes , so we must use aligned 4 bytes - 12 bytes array and argsCount = 3

g2d

false - Use pawn default buffer to draw texture.

true - Use g2d buffer to draw texture - not supported now.

G2D_DYNAMIC_TEXTURE_MOSAIC alogrithm description

So in effect named 'mosaic' we have settings of 10 parameters each one 1 byte

Noise factors :

factor x : values from 0 to 10

factor y : values from 0 to 10

factor xy : values from 0 to 10

Time factors :

factor x : values from 0 to 10

factor y : values from 0 to 10

factor xy : values from 0 to 10

Color factors :

r : values from 0 to 10

g : values from 0 to 10

b : values from 0 to 10

Zoom factor :

zoom values from 0 to 10

For example we want to set all parameters above with values in order 1,2,3,4,5,6,7,8,9,10. Take in attention that each parameter is 1 byte we must make array of 32-bit values 0x04030201, 0x08070605, 0x00000A09

Example:

mosaic_effect_settings = { 0x04030201, 0x08070605, 0x00000A09  };
mosaic_effect_settings_length = 3;
abi_CMD_DYNAMIC_TEXTURE(G2D_DYNAMIC_TEXTURE_MOSAIC , currentTime, mosaic_effect_settings, mosaic_effect_settings_length);

Motion sensors

abi_MTD_GetFaceAccel(X/Y/Z)

Syntax:

 abi_MTD_GetFaceAccelX(const faceN)
 abi_MTD_GetFaceAccelY(const faceN)
 abi_MTD_GetFaceAccelZ(const faceN)

Description:

Get the value of acceleration along the requested axis.

Arguments

faceN

Number of the module face for which requested axis is belong.

abi_MTD_GetFaceGyro(X/Y/Z)

Syntax:

 abi_MTD_GetFaceGyroX(const faceN)
 abi_MTD_GetFaceGyroY(const faceN)
 abi_MTD_GetFaceGyroZ(const faceN)

Description:

Get the gyro value around the requested axis.

Arguments

faceN

Number of the module face for which requested axis is belong.

abi_MTD_GetTapFace

Syntax:

 abi_MTD_GetTapFace()

Description:

Get the face ID which was tapped. ID is not a face number which is used for drawing in abi_CMD_G2D_BEGIN_DISPLAY or abi_CMD_REDRAW, but that number can be calculated by subtracting by one from ID value. See possible values below.

Return values:

MTD_TAP_DIRECTION_NONE = 0

Indicates that the module wan not tapped.

MTD_TAP_DIRECTION_X = 1

MTD_TAP_DIRECTION_Y = 2

MTD_TAP_DIRECTION_Z = 3

Indicated direction of tap.

abi_MTD_IsTapOpposite

Syntax:

 abi_MTD_IsTapOpposite()

Description:

Get the flag if the tap was detected in opposite direction.

abi_MTD_GetTapsCount

Syntax:

 abi_MTD_GetTapsCount()

Description:

Get the count of subsequent taps. Tap is treated as a subsequent if it was detected within predefined interval (350ms). Count will be zero until sequence is finished, i.e. next tap is not detected within interval.

abi_checkShake

Syntax:

 abi_checkShake()

Description:

Checks if the number of shakes of the cube was more than a certain threshold then exits the script

Examples

1. Flash the face on which tap was detected. Print an ID of that face. Color of the flash depends on taps count: red - one tap, green - two taps and blue - three.

new delay = 0;
new color = 0x000000; 
ONTICK() {
  if (!color) {
    switch (abi_MTD_GetTapsCount()) {
    case 1:
      color = 0xff0000;
    case 2:
      color = 0x00ff00;
    case 3:
      color = 0x0000ff;
    }
  }
  if (delay % 25 == 0) {
    for (new i = 0; i < FACES_MAX; i++) {
      if (i == (abi_MTD_GetTapFace() - 1)) {
        abi_CMD_FILL_2(color);
        color = 0x000000;
        switch (abi_MTD_GetTapFace()) {
        case 1:
          abi_CMD_TEXT(['1', '\0'], -1, 120, 120, 14, 0, 0xff, 0xff, 0xff);
        case 2:
          abi_CMD_TEXT(['2', '\0'], -1, 120, 120, 14, 0, 0xff, 0xff, 0xff);
        case 3:
          abi_CMD_TEXT(['3', '\0'], -1, 120, 120, 14, 0, 0xff, 0xff, 0xff);
        }
      } else {
        abi_CMD_FILL(0, 0, 0);
      }
      abi_CMD_REDRAW(i);
    }
  }
  delay++;
}

2. Exit from script

ONTICK() {
   if (abi_cubeN == 0) {
       abi_checkShake();
   }
   // Script logic
}

Save/load functions

abi_CMD_SAVE_STATE

Syntax:

 bool:abi_CMD_SAVE_STATE(const data[], size = sizeof(data))

Description:

Save maximum 256 bytes of data to wowcube flash memory.

Arguments

data

Game data to save.

size

Size of game data.

Return values:

return false

If size is bigger then 256 bytes.

abi_CMD_LOAD_STATE

Syntax:

 abi_CMD_LOAD_STATE()

Description:

Sends a command requesting the platform to load script data. The response from the platform is not instantaneous and takes several milliseconds.

Examples

1. Load data at the start.

// This function is called when a response is received from the platform
ON_LOAD_GAME_DATA (const pkt[]) {
   // Deserialize pkt
   currentLevelNumber = pkt[1]; // Starting with 1 cause 0 pkt element holding command ID
   score = pkt[2];
   moves = pkt[3];
   ...
   record = pkt[GAME_SAVE_SIZE];
}
ON_INIT () {
   abi_CMD_LOAD_STATE ();
}

2. Save the data after the end of the level.

SaveGameState () {
   new saveData [GAME_SAVE_SIZE];
   // Assign all necessary data
   saveData[0] = currentLevelNumber;
   saveData[1] = score;
   saveData[2] = moves;
   ...
   saveData[GAME_SAVE_SIZE - 1] = record;
   
   abi_CMD_SAVE_STATE (saveData);
}
ON_CHECK_ROTATE () {
   if (isLevelFinished) {
       SaveGameState();
   }
}

Time functions

abi_GetTime

Syntax:

 abi_GetTime()

Description:

Get current time in milliseconds.

Examples

new previousTime = 0;
new currentTime = 0;
new deltaTime = 0;
ON_INIT() {
   previousTime = abi_GetTime();
}
ONTICK() {
    currentTime = abi_GetTime();
    deltaTime = currentTime - previousTime;
    previousTime = currentTime;
}

Topology functions

get cube/face

Syntax:

 abi_topCubeN(const _cubeN, const _faceN)
 abi_topFaceN(const _cubeN, const _faceN)
 abi_rightCubeN(const _cubeN, const _faceN)
 abi_rightFaceN(const _cubeN, const _faceN)
 abi_bottomCubeN(const _cubeN, const _faceN)
 abi_bottomFaceN(const _cubeN, const _faceN)
 abi_leftCubeN(const _cubeN, const _faceN)
 abi_leftFaceN(const _cubeN, const _faceN)

Description:

Returns the cube / screen located at the top / bottom / left / right of the specified in parameters.

Examples

Find diagonal face and cube

new diagonalCube = CUBES_MAX;
new diagonalFace = FACES_MAX;
new topCube = abi_topCubeN(cube, face);
new topFace = abi_topFaceN(cube, face);
if (topCube < CUBES_MAX) {
    diagonalCube = abi_topCubeN(topCube, topFace);
    if (diagonalCube < CUBES_MAX) {
        diagonalFace = abi_topFaceN(topCube, topFace);
    }
}

Sound functions

abi_CMD_PLAYSND

Syntax:

 abi_CMD_PLAYSND(const id, const volume)

Description:

Play chosen sound with a given volume.

Arguments

id

Sound serial number in the application package.

volume

The sound volume.

Messages

abi_CMD_NET_TX

Syntax:

 abi_CMD_NET_TX(const line_tx, const TTL, const data[])

Description:

Send data through given UART line with given TTL.

Arguments

line_tx

UART line for sending a message. Each module has 3 UART lines.

TTL

Message time to live. How many modules message will pass through before stopping. For example, set TTL to 0 message will transfer only to the neighbor module. Set TTL to 1 message will transfer to a neighbor of neighbor. Maximum TTL is 2.

data

Data array to send. Maximum can be sent 20 bytes. The first 4 bytes are message general information that automatically adds before sending. The maximum useful data that can be sent are 16 bytes. Taking into account net command name 15 bytes.

Examples

We want to receive data only from 0 module

// define net command
#define NEW_TEST_NET_COMMAND P2P_CMD_BASE_SCRIPT_1 + 1

// create message to send
Send_Test_Message() {
   new data[4];
   data[0] = NEW_TEST_NET_COMMAND | (abi_cubeN << 8);
   data[1] = add_game_data;
   // using bitwise operations send more data
   data[2] = add_script_data_1 | (add_script_data_2 << 8) | (add_script_data_3 << 16) | (add_script_data_4 << 24);
   data[3] = add_game_data_1 | (add_game_data_2 << 16);
   
   // send message through UART
   abi_CMD_NET_TX(0, NET_BROADCAST_TTL_MAX, data);
   abi_CMD_NET_TX(1, NET_BROADCAST_TTL_MAX, data);
   abi_CMD_NET_TX(2, NET_BROADCAST_TTL_MAX, data);
}

// process the received message
ON_CMD_NET_RX (const pkt[]) {
   // get 4 byte from incoming packet to get net command because first 4 bytes are general info
   switch (abi_ByteN(pkt, 4)) {
       case NEW_TEST_NET_COMMAND: {
           if (abi_ByteN(pkt, 5) == 0) {
               game_data = pkt[2];
               script_data_1 = abi_ByteN(pkt, 12);
               script_data_2 = abi_ByteN(pkt, 13);
               script_data_3 = abi_ByteN(pkt, 14);
               script_data_4 = abi_ByteN(pkt, 15);
               game_data_1 = pkt[4] & 0xFFFF;
               game_data_2 = (pkt[4] >> 16) & 0xFFFF;
           }
       }
   }
}

Physics functions

PHYSICS_CIRCLE_DATA

Syntax:

 #define PHYSICS_CIRCLE_DATA .posX, .posY, .simplePosX, .simplePosY, .spdX, .spdY, .mass, .radius, .CoR, .cube, .face, .cubeT, .faceT

Description:

PAWN symbolic subscript which represent stucture.

Fields

posX

Circle position on X axis (fixed point)

posY

Circle position on Y axis (fixed point)

simplePosX

Circle position on X axis

simplePosY

Circle position on Y axis

spdX

Circle X speed

spdY

Circle Y speed

mass

Circle mass (fixed point)

radius

Circle radius

CoR

Coefficient of restitution (fixed point)

cube

Module owner of this circle

face

Face owner of this circle

cubeT

Cube transfer, last module owner. Can be used for resending messages

faceT

Face transfer, last face owner. Can be used for resending messages

Physics_Circle_Vs_Circle_obj

Syntax:

 Physics_Circle_Vs_Circle_obj(circle1[PHYSICS_CIRCLE_DATA], circle2[PHYSICS_CIRCLE_DATA])

Description:

Check circle versus circle collision.

Arguments:

circle1

First circle object.

circle2

Second circle object.

Physics_Circle_vs_AABB_obj

Syntax:

 Physics_Circle_vs_AABB_obj(circle[PHYSICS_CIRCLE_DATA], rectX, rectY, rectWidth, rectHeight, fakeCircle[PHYSICS_CIRCLE_DATA] = 0)

Description:

Check circle versus rectangle collision.

Arguments:

circle

Circle object.

rectX

Rectangle X coordinate.

rectY

Rectangle Y coordinate.

rectWidth

Rectangle width.

rectHeight

Rectangle height.

fakeCircle

In case of collision returns the collision point.

Physics_Circle_Vs_LineSegment

Syntax:

 Physics_Circle_Vs_LineSegment(circle[PHYSICS_CIRCLE_DATA], lineSX, lineSY, lineEX, lineEY, fakeCircle[PHYSICS_CIRCLE_DATA] = 0)

Description:

Check circle versus line segment collision.

Arguments:

circle

Circle object.

lineSX

Line start X coordinates.

lineSY

Line start Y coordinate.

lineEX

Line end X coordinate.

lineEY

Line end Y coordinate.

fakeCircle

In case of collision returns the collision point.

Physics_Res_CvC_Coll_Massless

Syntax:

 Physics_Res_CvC_Coll_Massless(circle1[PHYSICS_CIRCLE_DATA], circle2[PHYSICS_CIRCLE_DATA])

Description:

Collision resolves without using object mass.

Arguments:

circle1

First circle object.

circle2

Second circle object.

Physics_Res_CvC_Coll_Mass

Syntax:

 Physics_Res_CvC_Coll_Mass(circle1[PHYSICS_CIRCLE_DATA], circle2[PHYSICS_CIRCLE_DATA])

Description:

Resolves collision using object mass.

Arguments:

circle1

First circle object.

circle2

Second circle object.

Physics_DeserializeCircle

Syntax:

 Physics_DeserializeCircle(serializedData_1, serializedData_2, circle[PHYSICS_CIRCLE_DATA])

Description:

Deserialize circle object.

Arguments:

serializedData_1

First part of serialized circle data.

serializedData_2

Second part of serialized circle data.

circle

Circle object where need to save deserialized data.

Physics_SerializeCircle

Syntax:

 Physics_SerializeCircle(obj[PHYSICS_CIRCLE_DATA], &serializedData_1, &serializedData_2)

Description:

Serialize circle object.

Arguments:

circle

Circle object to serialize.

serializedData_1

Return first part of serialized circle data.

serializedData_2

Return second part of serialized circle data.

Physics_Overlap

Syntax:

 Physics_Overlap(overlap, positionDifference, distance)

Description:

Returns the distance by which objects overlap.

Arguments:

overlap

Half distance between two points.

positionDifference

Position difference between two point in one axis. Example - first point position X is 10, second is 6. Then position difference is 10-6=4.

distance

Distance between two points.

Examples

1. Create circle object.

new ball_1[PHYSICS_CIRCLE_DATA];
ball_1.posX = 180 << 8;
ball_1.posY = 180 << 8;
ball_1.simplePosX = 200;
ball_1.simplePosY = 180;
ball_1.spdX = -155;
ball_1.spdY = -155;
ball_1.mass = 5 << 8;
ball_1.radius = 16;
ball_1.cube = 0;
ball_1.face = 0;
ball_1.CoR = 150;

2. Check collision of two circles and resolve it.

if (Physics_Circle_Vs_Circle_obj(ball_1, ball_2)) {
   // Resolve collision
   Physics_Res_CvC_Coll_Massless(ball_1, ball_2);
}

3. Check collision of circle versus rectangle and resolve it.

new fakeCircle[PHYSICS_CIRCLE_DATA];
if (Physics_Circle_vs_AABB_obj(ball, rectanglePosX, rectanglePosY, rectangleWidth, rectangleHeight, fakeCircle)) {
   // Resolve collision    
   Physics_Res_CvC_Coll_Mass(ball, fakeCircle);
}

4. Sending and receiving circle object.

// Sending message with ball object
SendBall (const pktNumber) {
   new data[4];
   new serializedData_1, serializedData_2;
   // Serialize 'ball' data
   Physics_SerializeCircle(ball, serializedData_1, serializedData_2);
   // Prepare message
   data[0] = P2P_CMD_SEND_BALL;
   data[1] = serializedData_1;
   data[2] = serializedData_2;
   data[3] = pktNumber;
   // Broadcast message
   abi_CMD_NET_TX(0, NET_BROADCAST_TTL_MAX, data);
   abi_CMD_NET_TX(1, NET_BROADCAST_TTL_MAX, data);
   abi_CMD_NET_TX(2, NET_BROADCAST_TTL_MAX, data);
}

// Receiving message with ball object
case P2P_CMD_SEND_BALL: {
   new packetNumberReceived = pkt[4];
   if ((ballPacketNumber < packetNumberReceived) || ((ballPacketNumber - packetNumberReceived) > (0x7FFFFFFF >> 1))) {
      ballPacketNumber = packetNumberReceived;
      Physics_DeserializeCircle(pkt[2], pkt[3], ball);
   }
}