draw_shapes.c

/**
 * @file draw_shapes.c
 * @author Lukas Nejezchleb (nejezluk@fel.cvut.cz)
 * @brief Module with functions to draw shapes to the frame buffer
 * @version 0.1
 * @date 2021-05-04
 * 
 * @copyright Copyright (c) 2021
 * 
 */

#include "draw_shapes.h"
#include <stdlib.h>
#include "config.h"

int pixel_dist_squared(int x1, int y1, int x2, int y2)
{
    return ((x1 - x2) * (x1 - x2) + (y1 - y2) * (y1 - y2));
}

void draw_circle(fb_data *frame, int x, int y, int radius, uint16_t color)
{
    for (int row = y - radius; row < y + radius; row++)
    {
        for (int col = x - radius; col < x + radius; col++)
        {
            if (row > 0 && col > 0 && row < frame->height && col < frame->width)
            {
                if (pixel_dist_squared(col, row, x, y) <= (radius * radius))
                {
                    frame->fb[row * frame->width + col] = color;
                }
            }
        }
    }
}

void draw_rectangle(fb_data *frame, int x, int y, int width, int height, uint16_t color)
{
    for (int i = 0; i < width; ++i)
    {
        if ((x + i >= 0) && (x + i < frame->width))
        {
            for (int j = 0; j < height; ++j)
            {
                if ((y + j >= 0) && (y + j < frame->height))
                {
                    // place on the screen
                    frame->fb[(y + j) * frame->width + x + i] = color;
                }
            }
        }
    }
}

void set_background(fb_data *frame, uint16_t color)
{
    for (int i = 0; i < frame->width * frame->height; ++i)
    {
        frame->fb[i] = color;
    }
}

void draw_ghost_shape(fb_data *frame, int x, int y, int scale, uint16_t color)
{
    // offset x and y so the ghost would be centered around
    x = x - scale * 4; // 4 is half of bitsize of uint8_t
    y = y - scale * 4; // 4 is half of height of ghost bitmap
    uint8_t ghost_bitmap[] = {0x3c, 0x7e, 0x7e, 0xdb, 0xff, 0xff, 0xff, 0xdb};
    /*
      xxxx   
     xxxxxx 
     xxxxxx
    xx xx xx
    xxxxxxxx
    xxxxxxxx
    xxxxxxxx
    xx xx xx
    */
    for (int i = 0; i < 8; ++i)
    { //for every row int ghost bitmap

        for (int j = 0; j < 8; ++j)
        { //for every bit in uint8_t ghost bitmap

            if ((ghost_bitmap[i] & (1 << (8 - j - 1))) != 0)
            {
                draw_rectangle(frame, x + j * scale, y + i * scale, scale, scale, color);
            }
        }
    }
}

void draw_pacman_dir(fb_data *frame, int x, int y, int radius, uint16_t color, int direction)
{
    for (int row = y - radius; row < y + radius; row++)
    {
        for (int col = x - radius; col < x + radius; col++)
        {
            if (row > 0 && col > 0 && row < frame->height && col < frame->width)
            {
                if ((pixel_dist_squared(col, row, x, y) <= (radius * radius)) && 
                        (abs(x - col) > (y - row)) && direction == UP)
                {
                    frame->fb[row * frame->width + col] = color; //drawing pacman facing up
                }
                else if ((pixel_dist_squared(col, row, x, y) <= (radius * radius)) &&
                         (abs(x - col) > (row - y)) && direction == DWN)
                {
                    frame->fb[row * frame->width + col] = color; //drawing pacman facing down
                }
                else if ((pixel_dist_squared(col, row, x, y) <= (radius * radius)) &&
                         (abs(row - y) > (col-x)) && direction == RIGHT)
                {
                    frame->fb[row * frame->width + col] = color; //drawing pacman facing right
                }
                else if ((pixel_dist_squared(col, row, x, y) <= (radius * radius)) &&
                         (abs(row - y) > (x-col)) && direction == LEFT)
                {
                    frame->fb[row * frame->width + col] = color; //drawing pacman facing left
                }
            }
        }
    }
}