comparison: components/u8g2/csrc/u8g2_line.c
components/u8g2/csrc/u8g2_line.c
- changeset 0
- 88d965579617
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| -1:000000000000 | 0:88d965579617 |
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| 1 /* | |
| 2 | |
| 3 u8g2_box.c | |
| 4 | |
| 5 Universal 8bit Graphics Library (https://github.com/olikraus/u8g2/) | |
| 6 | |
| 7 Copyright (c) 2016, olikraus@gmail.com | |
| 8 All rights reserved. | |
| 9 | |
| 10 Redistribution and use in source and binary forms, with or without modification, | |
| 11 are permitted provided that the following conditions are met: | |
| 12 | |
| 13 * Redistributions of source code must retain the above copyright notice, this list | |
| 14 of conditions and the following disclaimer. | |
| 15 | |
| 16 * Redistributions in binary form must reproduce the above copyright notice, this | |
| 17 list of conditions and the following disclaimer in the documentation and/or other | |
| 18 materials provided with the distribution. | |
| 19 | |
| 20 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND | |
| 21 CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, | |
| 22 INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF | |
| 23 MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE | |
| 24 DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR | |
| 25 CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, | |
| 26 SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT | |
| 27 NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; | |
| 28 LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER | |
| 29 CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, | |
| 30 STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) | |
| 31 ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF | |
| 32 ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | |
| 33 | |
| 34 */ | |
| 35 | |
| 36 #include "u8g2.h" | |
| 37 | |
| 38 | |
| 39 void u8g2_DrawLine(u8g2_t *u8g2, u8g2_uint_t x1, u8g2_uint_t y1, u8g2_uint_t x2, u8g2_uint_t y2) | |
| 40 { | |
| 41 u8g2_uint_t tmp; | |
| 42 u8g2_uint_t x,y; | |
| 43 u8g2_uint_t dx, dy; | |
| 44 u8g2_int_t err; | |
| 45 u8g2_int_t ystep; | |
| 46 | |
| 47 uint8_t swapxy = 0; | |
| 48 | |
| 49 /* no intersection check at the moment, should be added... */ | |
| 50 | |
| 51 if ( x1 > x2 ) dx = x1-x2; else dx = x2-x1; | |
| 52 if ( y1 > y2 ) dy = y1-y2; else dy = y2-y1; | |
| 53 | |
| 54 if ( dy > dx ) | |
| 55 { | |
| 56 swapxy = 1; | |
| 57 tmp = dx; dx =dy; dy = tmp; | |
| 58 tmp = x1; x1 =y1; y1 = tmp; | |
| 59 tmp = x2; x2 =y2; y2 = tmp; | |
| 60 } | |
| 61 if ( x1 > x2 ) | |
| 62 { | |
| 63 tmp = x1; x1 =x2; x2 = tmp; | |
| 64 tmp = y1; y1 =y2; y2 = tmp; | |
| 65 } | |
| 66 err = dx >> 1; | |
| 67 if ( y2 > y1 ) ystep = 1; else ystep = -1; | |
| 68 y = y1; | |
| 69 | |
| 70 #ifndef U8G2_16BIT | |
| 71 if ( x2 == 255 ) | |
| 72 x2--; | |
| 73 #else | |
| 74 if ( x2 == 0xffff ) | |
| 75 x2--; | |
| 76 #endif | |
| 77 | |
| 78 for( x = x1; x <= x2; x++ ) | |
| 79 { | |
| 80 if ( swapxy == 0 ) | |
| 81 u8g2_DrawPixel(u8g2, x, y); | |
| 82 else | |
| 83 u8g2_DrawPixel(u8g2, y, x); | |
| 84 err -= (uint8_t)dy; | |
| 85 if ( err < 0 ) | |
| 86 { | |
| 87 y += (u8g2_uint_t)ystep; | |
| 88 err += (u8g2_uint_t)dx; | |
| 89 } | |
| 90 } | |
| 91 } | |
| 92 |
