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| Rev | Author | Line No. | Line |
|---|---|---|---|
| 2 | mjames | 1 | /* |
| 2 | * displayclass.cpp |
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| 3 | * |
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| 4 | * Created on: 31 Oct 2020 |
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| 5 | * Author: mike |
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| 6 | */ |
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| 7 | |||
| 8 | #include "libOLED/displayclass.H" |
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| 9 | |||
| 10 | #include <cstring> |
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| 11 | #include <cstdlib> |
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| 12 | namespace |
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| 13 | { |
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| 14 | uint8_t const SSD1306_SETCONTRAST = 0x81; |
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| 15 | uint8_t const SSD1306_DISPLAYALLON_RESUME = 0xA4; |
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| 16 | uint8_t const SSD1306_DISPLAYALLON = 0xA5; |
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| 17 | uint8_t const SSD1306_NORMALDISPLAY = 0xA6; |
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| 18 | uint8_t const SSD1306_INVERTDISPLAY = 0xA7; |
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| 19 | uint8_t const SSD1306_DISPLAYOFF = 0xAE; |
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| 20 | uint8_t const SSD1306_DISPLAYON = 0xAF; |
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| 21 | |||
| 22 | uint8_t const SSD1306_SETDISPLAYOFFSET = 0xD3; |
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| 23 | uint8_t const SSD1306_SETCOMPINS = 0xDA; |
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| 24 | |||
| 25 | uint8_t const SSD1306_SETVCOMDETECT = 0xDB; |
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| 26 | |||
| 27 | uint8_t const SSD1306_SETDISPLAYCLOCKDIV = 0xD5; |
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| 28 | uint8_t const SSD1306_SETPRECHARGE = 0xD9; |
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| 29 | |||
| 30 | uint8_t const SSD1306_SETMULTIPLEX = 0xA8; |
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| 31 | |||
| 32 | uint8_t const SSD1306_SETLOWCOLUMN = 0x00; |
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| 33 | uint8_t const SSD1306_SETHIGHCOLUMN = 0x10; |
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| 34 | |||
| 35 | uint8_t const SSD1306_SETSTARTLINE = 0x40; |
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| 36 | |||
| 37 | uint8_t const SSD1306_MEMORYMODE = 0x20; |
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| 38 | uint8_t const SSD1306_COLUMNADDR = 0x21; |
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| 39 | uint8_t const SSD1306_PAGEADDR = 0x22; |
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| 40 | |||
| 41 | uint8_t const SSD1306_COMSCANINC = 0xC0; |
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| 42 | uint8_t const SSD1306_COMSCANDEC = 0xC8; |
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| 43 | |||
| 44 | uint8_t const SSD1306_SEGREMAP = 0xA0; |
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| 45 | |||
| 46 | uint8_t const SSD1306_CHARGEPUMP = 0x8D; |
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| 47 | |||
| 48 | uint8_t const SSD1306_EXTERNALVCC = 0x1; |
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| 49 | uint8_t const SSD1306_SWITCHCAPVCC = 0x2; |
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| 50 | |||
| 11 | mjames | 51 | // Scrolling #defines |
| 2 | mjames | 52 | uint8_t const SSD1306_ACTIVATE_SCROLL = 0x2F; |
| 53 | uint8_t const SSD1306_DEACTIVATE_SCROLL = 0x2E; |
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| 54 | uint8_t const SSD1306_SET_VERTICAL_SCROLL_AREA = 0xA3; |
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| 55 | uint8_t const SSD1306_RIGHT_HORIZONTAL_SCROLL = 0x26; |
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| 56 | uint8_t const SSD1306_LEFT_HORIZONTAL_SCROLL = 0x27; |
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| 57 | uint8_t const SSD1306_VERTICAL_AND_RIGHT_HORIZONTAL_SCROLL = 0x29; |
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| 58 | uint8_t const SSD1306_VERTICAL_AND_LEFT_HORIZONTAL_SCROLL = 0x2A; |
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| 59 | |||
| 11 | mjames | 60 | template <class T> |
| 61 | void |
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| 62 | swap(T &x, T &y) |
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| 63 | { |
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| 64 | T temp = x; |
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| 65 | x = y; |
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| 66 | y = temp; |
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| 67 | } |
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| 2 | mjames | 68 | |
| 11 | mjames | 69 | template <class T> |
| 70 | T abs(T x) |
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| 71 | { |
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| 72 | return x < 0 ? -x : x; |
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| 73 | } |
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| 2 | mjames | 74 | |
| 75 | } |
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| 76 | // provided to allow a destructor to destroy something not deleted |
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| 77 | // this is only OK because destructors shouldnt be needed |
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| 11 | mjames | 78 | void operator delete(void *data, unsigned int f) |
| 6 | mjames | 79 | { |
| 11 | mjames | 80 | (void)data; |
| 81 | (void)f; |
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| 6 | mjames | 82 | } |
| 2 | mjames | 83 | |
| 84 | // provided to implement an "error handler" on pure virtual |
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| 6 | mjames | 85 | extern "C" void |
| 11 | mjames | 86 | __cxa_pure_virtual() |
| 2 | mjames | 87 | { |
| 6 | mjames | 88 | while (1) |
| 89 | ; |
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| 2 | mjames | 90 | } |
| 91 | |||
| 11 | mjames | 92 | display_t::display_t(int const width, int const height, int const ramwidth, |
| 93 | uint8_t *const data) : m_width(width), m_height(height), m_ramwidth(ramwidth), m_cursor_x(0), m_cursor_y(0), m_rotation(0), m_colour(WHITE), m_data(data) |
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| 2 | mjames | 94 | { |
| 95 | } |
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| 96 | |||
| 11 | mjames | 97 | display_t::~display_t() |
| 2 | mjames | 98 | { |
| 99 | } |
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| 100 | |||
| 7 | mjames | 101 | void display_t::reset() |
| 102 | { |
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| 103 | oledReset(); |
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| 104 | } |
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| 105 | |||
| 11 | mjames | 106 | void display_t::init() |
| 2 | mjames | 107 | { |
| 108 | uint8_t const vccstate = SSD1306_EXTERNALVCC; |
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| 109 | |||
| 11 | mjames | 110 | oledSetCD(0); |
| 2 | mjames | 111 | |
| 112 | // Init sequence for 128x32 or 128x64 OLED module |
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| 11 | mjames | 113 | oledWrite(SSD1306_DISPLAYOFF); // 0xAE |
| 114 | oledWrite(SSD1306_SETDISPLAYCLOCKDIV); // 0xD5 |
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| 115 | oledWrite(0x80); // the suggested ratio 0x80 |
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| 116 | oledWrite(SSD1306_SETMULTIPLEX); // 0xA8 |
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| 117 | oledWrite(m_height - 1); |
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| 118 | oledWrite(SSD1306_SETDISPLAYOFFSET); // 0xD3 |
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| 119 | oledWrite(0x0); // no offset |
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| 120 | oledWrite(SSD1306_SETSTARTLINE | 0x0); // line #0 |
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| 121 | oledWrite(SSD1306_CHARGEPUMP); // 0x8D |
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| 122 | oledWrite(vccstate == SSD1306_EXTERNALVCC ? 0x10 : 0x14); |
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| 123 | oledWrite(SSD1306_MEMORYMODE); // 0x20 |
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| 124 | oledWrite(0x00); // 0x0 act like ks0108 |
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| 125 | oledWrite(SSD1306_SEGREMAP | 0x1); |
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| 126 | oledWrite(SSD1306_COMSCANDEC); |
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| 127 | oledWrite(SSD1306_SETCOMPINS); // 0xDA |
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| 128 | oledWrite(m_height == 32 ? 0x02 : 0x12); |
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| 129 | oledWrite(SSD1306_SETCONTRAST); // 0x81 |
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| 130 | oledWrite(vccstate == SSD1306_EXTERNALVCC ? 0x9F : 0xCF); |
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| 131 | oledWrite(SSD1306_SETPRECHARGE); // 0xd9 |
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| 132 | oledWrite(vccstate == SSD1306_EXTERNALVCC ? 0x22 : 0xF1); |
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| 133 | oledWrite(SSD1306_SETVCOMDETECT); // 0xDB |
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| 134 | oledWrite(0x40); |
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| 135 | oledWrite(SSD1306_DISPLAYALLON_RESUME); // 0xA4 |
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| 136 | oledWrite(SSD1306_NORMALDISPLAY); // 0xA6 |
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| 2 | mjames | 137 | |
| 11 | mjames | 138 | oledWrite(SSD1306_DISPLAYON); //--turn on oled panel |
| 2 | mjames | 139 | |
| 11 | mjames | 140 | clearDisplay(); |
| 2 | mjames | 141 | } |
| 142 | |||
| 143 | uint8_t |
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| 11 | mjames | 144 | display_t::getRotation(void) |
| 2 | mjames | 145 | { |
| 146 | return m_rotation; |
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| 147 | } |
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| 148 | |||
| 149 | int16_t |
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| 11 | mjames | 150 | display_t::width(void) |
| 2 | mjames | 151 | { |
| 152 | switch (m_rotation) |
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| 11 | mjames | 153 | { |
| 154 | case 0: |
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| 155 | return m_width; |
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| 156 | break; |
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| 157 | case 1: |
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| 158 | return m_width; |
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| 159 | break; |
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| 160 | case 2: |
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| 161 | return m_height; |
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| 162 | break; |
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| 163 | case 3: |
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| 164 | return -m_width; |
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| 165 | break; |
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| 166 | } |
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| 2 | mjames | 167 | return 0; |
| 168 | } |
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| 169 | |||
| 170 | int16_t |
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| 11 | mjames | 171 | display_t::height(void) |
| 2 | mjames | 172 | { |
| 173 | switch (m_rotation) |
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| 11 | mjames | 174 | { |
| 175 | case 0: |
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| 176 | return m_height; |
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| 177 | break; |
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| 178 | case 1: |
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| 179 | return m_height; |
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| 180 | break; |
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| 181 | case 2: |
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| 182 | return m_width; |
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| 183 | break; |
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| 184 | case 3: |
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| 185 | return -m_height; |
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| 186 | break; |
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| 187 | } |
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| 2 | mjames | 188 | return 0; |
| 189 | } |
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| 190 | |||
| 191 | // the most basic function, set a single pixel |
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| 11 | mjames | 192 | void display_t::drawPixel(int16_t x, int16_t y, bool pixel) |
| 2 | mjames | 193 | { |
| 194 | if ((x < 0) || (x >= m_width) || (y < 0) || (y >= m_height)) |
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| 195 | return; |
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| 196 | |||
| 197 | // check rotation, move pixel around if necessary |
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| 198 | switch (m_rotation) |
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| 11 | mjames | 199 | { |
| 200 | case 1: |
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| 201 | swap(x, y); |
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| 202 | x = m_width - x - 1; |
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| 203 | break; |
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| 204 | case 2: |
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| 205 | x = m_width - x - 1; |
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| 206 | y = m_height - y - 1; |
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| 207 | break; |
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| 208 | case 3: |
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| 209 | swap(x, y); |
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| 210 | y = m_height - y - 1; |
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| 211 | break; |
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| 212 | } |
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| 2 | mjames | 213 | |
| 214 | // x is which column |
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| 7 | mjames | 215 | // BLACK, and 0, invert 0 |
| 216 | // WHITE, and 0, invert 1 |
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| 217 | // OVERLAY, and 1 (preserve) , invert 0/ |
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| 218 | // INVERT, and 1, (preserve) , invert 1 |
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| 219 | |||
| 220 | switch (m_colour) |
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| 11 | mjames | 221 | { |
| 222 | case BLACK: |
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| 223 | case WHITE: |
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| 224 | m_data[x + (y / 8) * m_width] &= ~(1 << (y & 7)); |
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| 225 | break; |
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| 226 | default: |
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| 227 | break; |
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| 228 | } |
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| 7 | mjames | 229 | uint8_t pixData = 0; |
| 230 | switch (m_colour) |
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| 11 | mjames | 231 | { |
| 232 | case BLACK: |
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| 233 | pixData = pixel ? 0 : 1; |
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| 234 | break; |
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| 235 | case WHITE: |
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| 236 | case OVERLAY: |
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| 237 | case INVERT: |
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| 238 | pixData = pixel ? 1 : 0; |
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| 239 | break; |
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| 240 | } |
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| 7 | mjames | 241 | |
| 242 | m_data[x + (y / 8) * m_width] ^= (pixData << (y & 7)); |
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| 2 | mjames | 243 | } |
| 244 | |||
| 11 | mjames | 245 | void display_t::invertDisplay(uint8_t i) |
| 2 | mjames | 246 | { |
| 11 | mjames | 247 | oledSetCD(0); |
| 248 | oledWrite(i ? SSD1306_INVERTDISPLAY : SSD1306_NORMALDISPLAY); |
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| 2 | mjames | 249 | } |
| 250 | |||
| 251 | // startscrollright |
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| 252 | // Activate a right handed scroll for rows start through stop |
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| 253 | // Hint, the display is 16 rows tall. To scroll the whole display, run: |
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| 254 | // display.scrollright(0x00, 0x0F) |
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| 11 | mjames | 255 | void display_t::startscrollright(uint8_t start, uint8_t stop) |
| 2 | mjames | 256 | { |
| 11 | mjames | 257 | oledSetCD(0); |
| 258 | oledWrite(SSD1306_RIGHT_HORIZONTAL_SCROLL); |
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| 259 | oledWrite(0X00); |
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| 260 | oledWrite(start); |
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| 261 | oledWrite(0X00); |
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| 262 | oledWrite(stop); |
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| 263 | oledWrite(0X00); |
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| 264 | oledWrite(0XFF); |
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| 265 | oledWrite(SSD1306_ACTIVATE_SCROLL); |
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| 2 | mjames | 266 | } |
| 267 | |||
| 268 | // startscrollleft |
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| 269 | // Activate a right handed scroll for rows start through stop |
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| 270 | // Hint, the display is 16 rows tall. To scroll the whole display, run: |
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| 271 | // display.scrollright(0x00, 0x0F) |
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| 11 | mjames | 272 | void display_t::startscrollleft(uint8_t start, uint8_t stop) |
| 2 | mjames | 273 | { |
| 11 | mjames | 274 | oledSetCD(0); |
| 275 | oledWrite(SSD1306_LEFT_HORIZONTAL_SCROLL); |
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| 276 | oledWrite(0X00); |
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| 277 | oledWrite(start); |
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| 278 | oledWrite(0X00); |
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| 279 | oledWrite(stop); |
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| 280 | oledWrite(0X00); |
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| 281 | oledWrite(0XFF); |
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| 282 | oledWrite(SSD1306_ACTIVATE_SCROLL); |
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| 2 | mjames | 283 | } |
| 284 | |||
| 285 | // startscrolldiagright |
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| 286 | // Activate a diagonal scroll for rows start through stop |
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| 287 | // Hint, the display is 16 rows tall. To scroll the whole display, run: |
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| 288 | // display.scrollright(0x00, 0x0F) |
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| 11 | mjames | 289 | void display_t::startscrolldiagright(uint8_t start, uint8_t stop) |
| 2 | mjames | 290 | { |
| 11 | mjames | 291 | oledSetCD(0); |
| 292 | oledWrite(SSD1306_SET_VERTICAL_SCROLL_AREA); |
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| 293 | oledWrite(0X00); |
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| 294 | oledWrite(m_height); |
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| 295 | oledWrite(SSD1306_VERTICAL_AND_RIGHT_HORIZONTAL_SCROLL); |
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| 296 | oledWrite(0X00); |
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| 297 | oledWrite(start); |
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| 298 | oledWrite(0X00); |
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| 299 | oledWrite(stop); |
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| 300 | oledWrite(0X01); |
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| 301 | oledWrite(SSD1306_ACTIVATE_SCROLL); |
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| 2 | mjames | 302 | } |
| 303 | |||
| 304 | // startscrolldiagleft |
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| 305 | // Activate a diagonal scroll for rows start through stop |
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| 306 | // Hint, the display is 16 rows tall. To scroll the whole display, run: |
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| 307 | // display.scrollright(0x00, 0x0F) |
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| 11 | mjames | 308 | void display_t::startscrolldiagleft(uint8_t start, uint8_t stop) |
| 2 | mjames | 309 | { |
| 11 | mjames | 310 | oledSetCD(0); |
| 311 | oledWrite(SSD1306_SET_VERTICAL_SCROLL_AREA); |
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| 312 | oledWrite(0X00); |
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| 313 | oledWrite(m_height); |
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| 314 | oledWrite(SSD1306_VERTICAL_AND_LEFT_HORIZONTAL_SCROLL); |
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| 315 | oledWrite(0X00); |
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| 316 | oledWrite(start); |
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| 317 | oledWrite(0X00); |
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| 318 | oledWrite(stop); |
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| 319 | oledWrite(0X01); |
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| 320 | oledWrite(SSD1306_ACTIVATE_SCROLL); |
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| 2 | mjames | 321 | } |
| 322 | |||
| 11 | mjames | 323 | void display_t::stopscroll(void) |
| 2 | mjames | 324 | { |
| 11 | mjames | 325 | oledSetCD(0); |
| 326 | oledWrite(SSD1306_DEACTIVATE_SCROLL); |
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| 2 | mjames | 327 | } |
| 328 | |||
| 13 | mjames | 329 | |
| 11 | mjames | 330 | void display_t::dim(uint8_t contrast) |
| 2 | mjames | 331 | { |
| 332 | |||
| 333 | // the range of contrast to too small to be really useful |
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| 334 | // it is useful to dim the display |
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| 335 | |||
| 11 | mjames | 336 | oledSetCD(0); |
| 337 | oledWrite(SSD1306_SETCONTRAST); |
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| 338 | oledWrite(contrast); |
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| 2 | mjames | 339 | } |
| 340 | |||
| 11 | mjames | 341 | void display_t::display(void) |
| 2 | mjames | 342 | { |
| 11 | mjames | 343 | oledSetCD(0); |
| 2 | mjames | 344 | // select entire display as window to write into |
| 11 | mjames | 345 | oledWrite(SSD1306_COLUMNADDR); |
| 346 | oledWrite(0); // Column start address (0 = reset) |
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| 347 | oledWrite(m_ramwidth - 1); // Column end address (127 = reset) |
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| 2 | mjames | 348 | |
| 11 | mjames | 349 | oledWrite(SSD1306_PAGEADDR); |
| 350 | oledWrite(0); // Page start address (0 = reset) |
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| 351 | oledWrite((m_height == 64) ? 7 : 3); // Page end address |
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| 2 | mjames | 352 | |
| 353 | int row; |
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| 354 | |||
| 355 | int col = m_ramwidth == 132 ? 2 : 0; |
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| 356 | for (row = 0; row < m_height / 8; row++) |
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| 11 | mjames | 357 | { |
| 358 | oledSetCD(0); |
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| 359 | // set the cursor to |
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| 360 | oledWrite(0xB0 + row); // set page address |
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| 361 | oledWrite(col & 0xf); // set lower column address |
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| 362 | oledWrite(0x10 | (col >> 4)); // set higher column address |
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| 2 | mjames | 363 | |
| 11 | mjames | 364 | oledSetCD(1); |
| 365 | oledWrite(m_data + row * m_width, m_width); |
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| 366 | } |
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| 2 | mjames | 367 | } |
| 368 | |||
| 369 | // clear everything |
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| 11 | mjames | 370 | void display_t::clearDisplay(colour_t colour) |
| 2 | mjames | 371 | { |
| 7 | mjames | 372 | switch (colour) |
| 11 | mjames | 373 | { |
| 374 | case WHITE: |
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| 375 | case OVERLAY: |
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| 376 | memset(m_data, 255, dataSize(m_width, m_height)); |
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| 377 | break; |
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| 378 | case BLACK: |
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| 379 | memset(m_data, 0, dataSize(m_width, m_height)); |
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| 380 | break; |
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| 381 | case INVERT: |
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| 382 | for (size_t i = 0; i < dataSize(m_width, m_height); i++) |
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| 383 | m_data[i] ^= 255; |
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| 384 | break; |
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| 385 | } |
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| 2 | mjames | 386 | } |
| 387 | |||
| 11 | mjames | 388 | void display_t::drawRectangle(int16_t x1, int16_t y1, int16_t x2, int16_t y2, |
| 389 | colour_t color) |
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| 6 | mjames | 390 | { |
| 391 | for (int16_t x = x1; x <= x2; x++) |
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| 392 | for (int16_t y = y1; y < y2; y++) |
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| 11 | mjames | 393 | { |
| 394 | switch (color) |
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| 6 | mjames | 395 | { |
| 11 | mjames | 396 | case BLACK: |
| 397 | m_data[x + (y / 8) * m_width] &= ~(1 << (y & 7)); |
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| 398 | break; |
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| 6 | mjames | 399 | |
| 11 | mjames | 400 | default: |
| 401 | case WHITE: |
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| 402 | case OVERLAY: |
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| 403 | m_data[x + (y / 8) * m_width] |= (1 << (y & 7)); |
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| 404 | break; |
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| 6 | mjames | 405 | |
| 11 | mjames | 406 | case INVERT: |
| 407 | m_data[x + (y / 8) * m_width] ^= (1 << (y & 7)); |
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| 408 | break; |
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| 6 | mjames | 409 | } |
| 11 | mjames | 410 | } |
| 6 | mjames | 411 | } |
| 412 | |||
| 2 | mjames | 413 | /* using Bresenham draw algorithm */ |
| 11 | mjames | 414 | void display_t::drawLine(int16_t x1, int16_t y1, int16_t x2, int16_t y2, |
| 415 | colour_t colour, int8_t pattern) |
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| 2 | mjames | 416 | { |
| 11 | mjames | 417 | int16_t x, y, dx, dy, // deltas |
| 418 | dx2, dy2, // scaled deltas |
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| 419 | ix, iy, // increase rate on the x and y axis |
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| 420 | err; // the error term |
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| 421 | int8_t patt = pattern; // drawing pattern bit mask 1= solid 10= dots , 111000 equal dot/dash |
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| 8 | mjames | 422 | |
| 11 | mjames | 423 | uint16_t i; // looping variable |
| 8 | mjames | 424 | |
| 425 | setPixelMode(colour); |
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| 426 | |||
| 2 | mjames | 427 | // identify the first pixel |
| 428 | x = x1; |
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| 429 | y = y1; |
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| 430 | |||
| 431 | // difference between starting and ending points |
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| 432 | dx = x2 - x1; |
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| 433 | dy = y2 - y1; |
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| 434 | |||
| 435 | // calculate direction of the vector and store in ix and iy |
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| 436 | if (dx >= 0) |
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| 437 | ix = 1; |
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| 438 | |||
| 439 | if (dx < 0) |
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| 11 | mjames | 440 | { |
| 441 | ix = -1; |
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| 442 | dx = abs(dx); |
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| 443 | } |
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| 2 | mjames | 444 | |
| 445 | if (dy >= 0) |
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| 446 | iy = 1; |
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| 447 | |||
| 448 | if (dy < 0) |
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| 11 | mjames | 449 | { |
| 450 | iy = -1; |
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| 451 | dy = abs(dy); |
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| 452 | } |
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| 2 | mjames | 453 | |
| 454 | // scale deltas and store in dx2 and dy2 |
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| 455 | dx2 = dx * 2; |
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| 456 | dy2 = dy * 2; |
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| 457 | |||
| 11 | mjames | 458 | // all variables are set and it's time to enter the main loop. |
| 2 | mjames | 459 | |
| 11 | mjames | 460 | if (dx > dy) // dx is the major axis |
| 461 | { |
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| 462 | // initialize the error term |
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| 463 | err = dy2 - dx; |
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| 464 | |||
| 465 | for (i = 0; i <= dx; i++) |
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| 2 | mjames | 466 | { |
| 11 | mjames | 467 | // draw pattern based on using pattern as a sequential bit mask. |
| 468 | if (patt & 1) |
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| 469 | drawPixel(x, y, 1); |
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| 470 | patt = (patt <= 1) ? pattern : patt >> 1; |
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| 2 | mjames | 471 | |
| 11 | mjames | 472 | if (err >= 0) |
| 473 | { |
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| 474 | err -= dx2; |
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| 475 | y += iy; |
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| 476 | } |
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| 477 | err += dy2; |
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| 478 | x += ix; |
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| 2 | mjames | 479 | } |
| 11 | mjames | 480 | } |
| 2 | mjames | 481 | |
| 11 | mjames | 482 | else // dy is the major axis |
| 483 | { |
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| 484 | // initialize the error term |
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| 485 | err = dx2 - dy; |
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| 486 | |||
| 487 | for (i = 0; i <= dy; i++) |
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| 2 | mjames | 488 | { |
| 11 | mjames | 489 | // draw pattern based on using pattern as a sequential bit mask. |
| 490 | if (patt & 1) |
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| 491 | drawPixel(x, y, 1); |
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| 492 | patt = (patt <= 1) ? pattern : patt >> 1; |
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| 493 | if (err >= 0) |
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| 494 | { |
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| 495 | err -= dy2; |
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| 496 | x += ix; |
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| 497 | } |
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| 498 | err += dx2; |
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| 499 | y += iy; |
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| 2 | mjames | 500 | } |
| 11 | mjames | 501 | } |
| 2 | mjames | 502 | } |