nodemcu-firmware/docs/en/modules/ucg.md

# ucg Module
Ucglib is a graphics library developed at [olikraus/ucglib](https://github.com/olikraus/ucglib) with support for color TFT displays. The NodeMCU firmware supports a subset of these:

- ILI9163
- ILI9341
- PCF8833
- SEPS225
- SSD1331
- SSD1351
- ST7735

This integration is based on [v1.3.3](https://github.com/olikraus/Ucglib_Arduino/releases/tag/v1.3.3).

## Overview

### SPI Connection

The HSPI module is used ([more information](http://d.av.id.au/blog/esp8266-hardware-spi-hspi-general-info-and-pinout/)), so certain pins are fixed:

* HSPI CLK  = GPIO14
* HSPI MOSI = GPIO13
* HSPI MISO = GPIO12 (not used)

All other pins can be assigned to any available GPIO:

* CS
* D/C
* RES (optional for some displays)

Also refer to the initialization sequence eg in [GraphicsTest.lua](https://github.com/nodemcu/nodemcu-firmware/blob/master/lua_examples/ucglib/GraphicsRest.lua):
```lua
spi.setup(1, spi.MASTER, spi.CPOL_LOW, spi.CPHA_LOW, 8, 8)
```

### Library Usage
The Lua bindings for this library closely follow ucglib's object oriented C++ API. Based on the ucg class, you create an object for your display type.

ILI9341 via SPI:
```lua
cs  = 8 -- GPIO15, pull-down 10k to GND
dc  = 4 -- GPIO2
res = 0 -- GPIO16, RES is optional YMMV
disp = ucg.ili9341_18x240x320_hw_spi(cs, dc, res)
```

This object provides all of ucglib's methods to control the display.
Again, refer to [GraphicsTest.lua](https://github.com/nodemcu/nodemcu-firmware/blob/master/lua_examples/ucglib/GraphicsTest.lua) to get an impression how this is achieved with Lua code. Visit the [ucglib homepage](https://github.com/olikraus/ucglib) for technical details.

### Displays
To get access to the display constructors, add the desired entries to the display table in [app/include/ucg_config.h](https://github.com/nodemcu/nodemcu-firmware/blob/master/app/include/ucg_config.h):
```c
#define UCG_DISPLAY_TABLE                          \
    UCG_DISPLAY_TABLE_ENTRY(ili9341_18x240x320_hw_spi, ucg_dev_ili9341_18x240x320, ucg_ext_ili9341_18) \
    UCG_DISPLAY_TABLE_ENTRY(st7735_18x128x160_hw_spi, ucg_dev_st7735_18x128x160, ucg_ext_st7735_18) \
```

### Fonts
ucglib comes with a wide range of fonts for small displays. Since they need to be compiled into the firmware image, you'd need to include them in [app/include/ucg_config.h](https://github.com/nodemcu/nodemcu-firmware/blob/master/app/include/ucg_config.h) and recompile. Simply add the desired fonts to the font table:
```c
#define UCG_FONT_TABLE                              \
    UCG_FONT_TABLE_ENTRY(font_7x13B_tr)             \
    UCG_FONT_TABLE_ENTRY(font_helvB12_hr)           \
    UCG_FONT_TABLE_ENTRY(font_helvB18_hr)           \
    UCG_FONT_TABLE_ENTRY(font_ncenR12_tr)           \
    UCG_FONT_TABLE_ENTRY(font_ncenR14_hr)
```
They'll be available as `ucg.<font_name>` in Lua.

## Display Drivers

Initialize a display via Hardware SPI.

- `ili9163_18x128x128_hw_spi()`
- `ili9341_18x240x320_hw_spi()`
- `pcf8833_16x132x132_hw_spi()`
- `seps225_16x128x128_univision_hw_spi()`
- `ssd1351_18x128x128_hw_spi()`
- `ssd1351_18x128x128_ft_hw_spi()`
- `ssd1331_18x96x64_univision_hw_spi()`
- `st7735_18x128x160_hw_spi()`

#### Syntax
`ucg.st7735_18x128x160_hw_spi(cs, dc, [res])`

#### Parameters
- `cs` GPIO pin for /CS
- `dc` GPIO pin for DC
- `res` GPIO pin for /RES (optional)

#### Returns
ucg display object

#### Example
```lua
spi.setup(1, spi.MASTER, spi.CPOL_LOW, spi.CPHA_LOW, spi.DATABITS_8, 0)

cs  = 8 -- GPIO15, pull-down 10k to GND
dc  = 4 -- GPIO2
res = 0 -- GPIO16, RES is optional YMMV
disp = ucg.st7735_18x128x160_hw_spi(cs, dc, res)
```

## Constants
Constants for various functions.

`ucg.FONT_MODE_TRANSPARENT`, `ucg.FONT_MODE_SOLID`, `ucg.DRAW_UPPER_RIGHT`,
`ucg.DRAW_UPPER_LEFT`, `ucg.DRAW_LOWER_RIGHT`, `ucg.DRAW_LOWER_LEFT`, `ucg.DRAW_ALL`

`ucg.font_7x13B_tr`, ...

# ucg.disp Sub-Module

## ucg.disp:begin()
See [ucglib begin()](https://github.com/olikraus/ucglib/wiki/reference#begin).

## ucg.disp:clearScreen()
See [ucglib clearScreen()](https://github.com/olikraus/ucglib/wiki/reference#clearscreen).

## ucg.disp:draw90Line()
See [ucglib draw90Line()](https://github.com/olikraus/ucglib/wiki/reference#draw90line).

## ucg.disp:drawBox()
See [ucglib drawBox()](https://github.com/olikraus/ucglib/wiki/reference#drawbox).

## ucg.disp:drawCircle()
See [ucglib drawCircle()](https://github.com/olikraus/ucglib/wiki/reference#drawcircle).

## ucg.disp:drawDisc()
See [ucglib drawDisc()](https://github.com/olikraus/ucglib/wiki/reference#drawdisc).

## ucg.disp:drawFrame()
See [ucglib drawFrame()](https://github.com/olikraus/ucglib/wiki/reference#drawframe).

## ucg.disp:drawGlyph()
See [ucglib drawGlyph()](https://github.com/olikraus/ucglib/wiki/reference#drawglyph).

## ucg.disp:drawGradientBox()
See [ucglib drawGradientBox()](https://github.com/olikraus/ucglib/wiki/reference#drawgradientbox).

## ucg.disp:drawGradientLine()
See [ucglib drawGradientLine()](https://github.com/olikraus/ucglib/wiki/reference#drawgradientline).

## ucg.disp:drawHLine()
See [ucglib drawHLine()](https://github.com/olikraus/ucglib/wiki/reference#drawhline).

## ucg.disp:drawLine()
See [ucglib drawLine()](https://github.com/olikraus/ucglib/wiki/reference#drawline).

## ucg.disp:drawPixel()
See [ucglib drawPixel()](https://github.com/olikraus/ucglib/wiki/reference#drawpixel).

## ucg.disp:drawRBox()
See [ucglib drawRBox()](https://github.com/olikraus/ucglib/wiki/reference#drawrbox).

## ucg.disp:drawRFrame()
See [ucglib drawRFrame()](https://github.com/olikraus/ucglib/wiki/reference#drawrframe).

## ucg.disp:drawString()
See [ucglib drawString()](https://github.com/olikraus/ucglib/wiki/reference#drawstring).

## ucg.disp:drawTetragon()
See [ucglib drawTetragon()](https://github.com/olikraus/ucglib/wiki/reference#drawtetragon).

## ucg.disp:drawTriangle()
See [ucglib drawTriangle()](https://github.com/olikraus/ucglib/wiki/reference#drawrtiangle).

## ucg.disp:drawVLine()
See [ucglib drawVline()](https://github.com/olikraus/ucglib/wiki/reference#drawvline).

## ucg.disp:getFontAscent()
See [ucglib getFontAscent()](https://github.com/olikraus/ucglib/wiki/reference#getfontascent).

## ucg.disp:getFontDescent()
See [ucglib getFontDescent()](https://github.com/olikraus/ucglib/wiki/reference#getfontdescent).

## ucg.disp:getHeight()
See [ucglib getHeight()](https://github.com/olikraus/ucglib/wiki/reference#getheight).

## ucg.disp:getStrWidth()
See [ucglib getStrWidth()](https://github.com/olikraus/ucglib/wiki/reference#getstrwidth).

## ucg.disp:getWidth()
See [ucglib getWidth()](https://github.com/olikraus/ucglib/wiki/reference#getwidth).

## ucg.disp:print()
See [ucglib print()](https://github.com/olikraus/ucglib/wiki/reference#print).

## ucg.disp:setClipRange()
See [ucglib setClipRange()](https://github.com/olikraus/ucglib/wiki/reference#setcliprange).

## ucg.disp:setColor()
See [ucglib setColor()](https://github.com/olikraus/ucglib/wiki/reference#setcolor).

## ucg.disp:setFont()
ucglib comes with a wide range of fonts for small displays. Since they need to be compiled into the firmware image, you'd need to include them in [app/include/ucg_config.h](https://github.com/nodemcu/nodemcu-firmware/blob/master/app/include/ucg_config.h) and recompile. Simply add the desired fonts to the font table:
```c
#define UCG_FONT_TABLE                              \
    UCG_FONT_TABLE_ENTRY(font_7x13B_tr)             \
    UCG_FONT_TABLE_ENTRY(font_helvB12_hr)           \
    UCG_FONT_TABLE_ENTRY(font_helvB18_hr)           \
    UCG_FONT_TABLE_ENTRY(font_ncenR12_tr)           \
    UCG_FONT_TABLE_ENTRY(font_ncenR14_hr)
```
They'll be available as `ucg.<font_name>` in Lua.

#### Syntax
`disp:setFont(font)`

#### Parameters
`font` constant to identify pre-compiled font

#### Returns
`nil`

#### Example
```lua
disp:setFont(ucg.font_7x13B_tr)
```

#### See also
[ucglib setFont()](https://github.com/olikraus/ucglib/wiki/reference#setfont)

## ucg.disp:setFontMode()
See [ucglib setFontMode()](https://github.com/olikraus/ucglib/wiki/reference#setfontmode).

## ucg.disp:setFontPosBaseline()
See [ucglib setFontPosBaseline()](https://github.com/olikraus/ucglib/wiki/reference#setfontposbaseline).

## ucg.disp:setFontPosBottom()
See [ucglib setFontPosBottom()](https://github.com/olikraus/ucglib/wiki/reference#setfontposbottom).

## ucg.disp:setFontPosCenter()
See [ucglib setFontPosCenter()](https://github.com/olikraus/ucglib/wiki/reference#setfontposcenter).

## ucg.disp:setFontPosTop()
See [ucglib setFontPosTop()](https://github.com/olikraus/ucglib/wiki/reference#setfontpostop).

## ucg.disp:setMaxClipRange()
See [ucglib setMaxClipRange()](https://github.com/olikraus/ucglib/wiki/reference#setmaxcliprange).

## ucg.disp:setPrintDir()
See [ucglib setPrintDir()](https://github.com/olikraus/ucglib/wiki/reference#setprintdir).

## ucg.disp:setPrintPos()
See [ucglib setPrintPos()](https://github.com/olikraus/ucglib/wiki/reference#setprintpos).

## ucg.disp:setRotate90()
See [ucglib setRotate90()](https://github.com/olikraus/ucglib/wiki/reference#setrotate90).

## ucg.disp:setRotate180()
See [ucglib setRotate180()](https://github.com/olikraus/ucglib/wiki/reference#setrotate180).

## ucg.disp:setRotate270()
See [ucglib setRotate270()](https://github.com/olikraus/ucglib/wiki/reference#setrotate270).

## ucg.disp:setScale2x2()
See [ucglib setScale2x2()](https://github.com/olikraus/ucglib/wiki/reference#setscale2x2).

## ucg.disp:undoClipRange()
See [ucglib undoClipRange()](https://github.com/olikraus/ucglib/wiki/reference#undocliprange).

## ucg.disp:undoRotate()
See [ucglib undoRotate()](https://github.com/olikraus/ucglib/wiki/reference#undorotate).

## ucg.disp:undoScale()
See [ucglib undoScale()](https://github.com/olikraus/ucglib/wiki/reference#undoscale).