diff options
Diffstat (limited to 'cbrll.c')
| -rw-r--r-- | cbrll.c | 186 |
1 files changed, 186 insertions, 0 deletions
@@ -0,0 +1,186 @@ +#include "cbrll.h" +/* this library stores the screen in a variable referred to in functions as map + * it takes the form of a 2 dimensional array of uint8_t + * takes char storing the on/off positions of 8 points, in braille encoding + * order, and prints the corresponding braille char + * maps maximum size is 200x200 pixels, which works out to a 50 by 100 array + */ + +void printbraille(uint8_t points) { + /* outputs braille characters, the encoding for braile is: + * 1 4 + * 2 5 + * 3 6 + * 7 8 + * with the block being in U+2800 to U+28FF + * in utf8 that's encoded + * 1110xxxx 10xxxxxx 10xxxxxx + * [1110](0010) [10](1000)87 [10]654321 + */ + printf("%c%c%c", + 0b11100010, + 0b10100000 | (points >> 6), + 0b10000000 | (points & 0b00111111)); +} +/* prints the map, clears output before aswell*/ +/*prints x1 to x2, y1 to y2 bytes of the map*/ +void printmap( uint8_t x1, uint8_t x2, uint8_t y1, uint8_t y2 ) { + uint8_t xi = x1; + uint8_t yi = y1; + /*terminal escape code to move the cursor to beginning of screen or 1,1*/ + printf("\033[1;1H"); + while (yi < y2) { + xi = 0; + while (xi < x2) { + printbraille(map[xi][yi]); + xi++; + } + printf("\n"); + yi++; + } +} +/* sets a pixel in the map, converts x,y coordinates to braille order + * if set is 0, then set it to 0 + * if 1, set to 1 + * if > 1, flip + * does not throw errors + */ +void setpixel(uint8_t x, uint8_t y,uint8_t set) { + /* anchor x and y coordinates, eg the index in map*/ + uint8_t ax; + uint8_t ay; + /*bitmask in braille order of the byte in mask*/ + uint8_t shift = 0x01; + /* check if out of bounds, since the arguments are unsigned, don't have + * to check below 0, doesn't throw errors + */ + if ( (x >= 200 ) || (y >= 200) ) { + return; + } + /* integer division rounds down, therefore dividing will always get the + * index + */ + ax = x/2; + ay = y/4; + /* + * maps to braille order based off of x and y offsets + * 1 4 + * 2 5 + * 3 6 + * 7 8 + */ + switch(x % 2) { + case 0: + switch (y % 4) { + case 0: + shift = shift << 0; + break; + case 1: + shift = shift << 1; + break; + case 2: + shift = shift << 2; + break; + case 3: + shift = shift << 6; + break; + } + break; + case 1: + switch (y % 4) { + case 0: + shift = shift << 3; + break; + case 1: + shift = shift << 4; + break; + case 2: + shift = shift << 5; + break; + case 3: + shift = shift << 7; + break; + } + break; + } + /* sets the bit based on set*/ + switch (set) { + case 0: + map[ax][ay] = map[ax][ay] & (~shift); + break; + case 1: + map[ax][ay] = map[ax][ay] | shift; + break; + default: + map[ax][ay] = ((~map[ax][ay]) & shift) | + ((~shift) & map[ax][ay]); + break; + } + return; +} +/*takes two points and draws a line between them, dot specifies that every nth x + * point be drawn, if dot != 1, then a dotted line is drawn + */ +void drawline(uint8_t x1, uint8_t y1, uint8_t x2, uint8_t y2, uint8_t dot) { + /*temporary x and y for switching x1,y1 and x2,y1 if x1>x2*/ + uint8_t tv; + /*number of x values to translate*/ + uint8_t dx; + /*number of y values to translate*/ + uint8_t dy; + /* for whether dy should be positive or negative, 1 pos, 0 neg*/ + uint8_t dir; + /*drawin index*/ + uint8_t xi = 0; + /*makes sure that x1 < x2, otherwise switch them arround*/ + if (x1 > x2) { + tv = x1; + x1 = x2; + x2 = tv; + tv = y1; + y1 = y2; + y2 = tv; + } + dx = x2 - x1; + /*find absolute + * dir is used since i'm planning to port to a platform that may not + * have signed ints. + */ + if (y1 > y2) { + dir = 0; + dy = y1 - y2; + } else { + dir = 1; + dy = y2 - y1; + } + /* + *For vertical Lines + * Uses xi as a y index now + */ + if (x1 == x2) { + while (xi <= dy) { + if (dir) { + setpixel(x1, y1 + xi, 1); + } else { + setpixel(x1, y1 - xi, 1); + } + xi++; + } + } + /* + * loop through x and draws y in line, dots done with modulus. + */ + while (xi <= (dx)) { + if ((xi % dot) == 0) { + if (dir) { + setpixel(x1 + xi, y1 + ((dy/dx * xi)), 1); + } else { + setpixel(x1 + xi, y1 - ((dy/dx * xi)), 1); + } + } + xi++; + } + + return; +} + |