240 lines
		
	
	
		
			8.4 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
			
		
		
	
	
			240 lines
		
	
	
		
			8.4 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
| #include <stdint.h>
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| #include <string.h>
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| #include "mandelbrot.h"
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| #include "st7735.h"
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| #include "benchmark.h"
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| #include "main.h"
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| 
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| #define RES_X             160
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| #define RES_Y             80
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| #define DEFAULT_CENTER_X  0
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| #define DEFAULT_CENTER_Y  0
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| #define STEP_SIZE         .1
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| #define ZOOM_SIZE         .1
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| 
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| #define DECIMAL_LOC           28
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| #define DOUBLE_SCALER         (1 << DECIMAL_LOC)
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| #define DOUBLE_TO_FIXED(val)  (int32_t)((val) * DOUBLE_SCALER)
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| #define FIXED_MULTIPLY(x,y)   ((((uint64_t)(x))*(y)) >> DECIMAL_LOC)
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| #define FIXED_TO_DOUBLE(val)  ((val) / (double)DOUBLE_SCALER)
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| 
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| #define INFTY     2
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| #define INFTY_SQR INFTY * INFTY
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| #define ITERS     255
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| #define INFTY_SQR_FIXED DOUBLE_TO_FIXED(INFTY_SQR)
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| 
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| //TODO move to some hardware.h or somethin
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| //channel order: B, G, R
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| #define R_BITS  5
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| #define G_BITS  6
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| #define B_BITS  5
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| 
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| //imaginary axis set automatically
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| #define CAM_DEF_MIN_R -1
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| #define CAM_DEF_MAX_R  1
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| 
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| //set controls 
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| #define CAM_MOVE_UP     BUTTON_UP     
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| #define CAM_MOVE_RIGHT  BUTTON_RIGHT
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| #define CAM_MOVE_DOWN   BUTTON_DOWN   
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| #define CAM_MOVE_LEFT   BUTTON_LEFT   
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| #define CAM_ZOOM_IN     BUTTON_A      
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| #define CAM_ZOOM_OUT    BUTTON_B      
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| 
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| struct camera {
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|   double min_r, min_i, max_r, max_i;
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| };
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| 
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| enum VIEW_MODES { VIEW_UNINIT, VIEW_MANDREL, VIEW_SHIP };
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| 
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| void init_colorscheme_mandrel(uint16_t *scheme) {
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|   uint16_t *tc = scheme;
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|   for(unsigned int i = 0; i < ITERS; i++) {
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|     if((i == 0) || (i == ITERS)) *tc = 0;
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|     else if(i < 128) *tc = (((((i - 64) << 2)+0x1f) & 0x1f) | (((((i - 128) << 1)+0x1f) & 0x1f) << (5+6)));
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|     else *tc = (-2*(i - 128)+0x1f) & 0xff;
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|     *tc = (*tc << 8) | (*tc >> 8); //convert to little endian
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|     tc++;
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|   }
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| }
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| 
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| void init_colorscheme_ship(uint16_t *scheme) {
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|   uint16_t *tc = scheme;
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|   for(unsigned int i = 0; i < ITERS; i++) {
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|     if((i == 0) || (i == ITERS)) *tc = 0;
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|     else *tc = (((i - (128)) << 1)+0x1f) << (5+6);
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|     tc++;
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|   }
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| }
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| 
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| void cam_shift(struct camera *cam, double step_r, double step_i) {
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|   double i_offset = (cam->max_i - cam->min_i) * step_i;
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|   double r_offset = (cam->max_r - cam->min_r) * step_r;
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|   cam->min_i += i_offset;
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|   cam->max_i += i_offset;
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|   cam->min_r += r_offset;
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|   cam->max_r += r_offset;
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| }
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| 
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| void cam_zoom(struct camera *cam, double zoom) {
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|   double i_scale = (cam->max_i - cam->min_i) * zoom;
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|   double r_scale = (cam->max_r - cam->min_r) * zoom;
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|   cam->min_i += i_scale;
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|   cam->max_i -= i_scale;
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|   cam->min_r += r_scale;
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|   cam->max_r -= r_scale;
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| }
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| 
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| 
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| //TODO look into border tracing; this is too slow. Change name
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| //
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| void render_mandelbrot(uint16_t *framebuffer, uint16_t *colorscheme, struct camera cam, int x0, int y0, int w, int h) {
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|   int32_t scale_i = DOUBLE_TO_FIXED((cam.max_i - cam.min_i) / (double)RES_Y);
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|   int32_t scale_r = DOUBLE_TO_FIXED((cam.max_r - cam.min_r) / (double)RES_X);
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|   int32_t c_i = DOUBLE_TO_FIXED((((cam.max_i - cam.min_i) * (RES_Y - y0)) / RES_Y) + cam.min_i);
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|   int32_t c_r0 = DOUBLE_TO_FIXED((((cam.max_r - cam.min_r) * x0) / RES_X) + cam.min_r);
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|   int32_t c_r, z_i, z_r, zn_r, z_r_2, z_i_2;
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|   size_t fb_index = 0;
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|   int i; 
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|   
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|   //for(;;);
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| 
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|   for(int y = y0; y < y0 + h; y++) {
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|     c_r = c_r0;
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|     for(int x = x0; x < x0 + w; x++) {
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|       z_i = 0;
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|       z_r = 0;
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|       for(i = 0; i < ITERS; i++) {
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|         z_r_2 = FIXED_MULTIPLY(z_r, z_r);
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|         z_i_2 = FIXED_MULTIPLY(z_i, z_i);
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| 
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|         zn_r = z_r_2 - z_i_2 + c_r;
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| 
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|         //z_i = abs(FIXED_MULTIPLY((DOUBLE_TO_FIXED(2)), (FIXED_MULTIPLY(z_r, z_i)))) + c_i;
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|         z_i = (FIXED_MULTIPLY(z_r, z_i) << 1)  + c_i;
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| 
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|         z_r = zn_r;
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| 
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|         if(z_i_2 + z_r_2 > INFTY_SQR_FIXED) break;
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|       }
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|       framebuffer[fb_index++] = colorscheme[i];
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|       c_r += scale_r;
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|     }
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|     c_i -= scale_i;
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|   }
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| }
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|   
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| 
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| 
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| #define FB_SIZE_X RES_X
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| #define FB_SIZE_Y RES_Y/2
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| 
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| //TODO rename
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| void draw_mandelbrot(int key_pressed) {
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|   static uint16_t framebuffer[FB_SIZE_X * FB_SIZE_Y];
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|   uint16_t columnbuffer[8*RES_Y];
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|   static bool bottom_buffered = true;
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|   //program flow is awful atm becuase I was planning something different; will be improved soon.
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|   static struct camera cam = {
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|     .min_r = CAM_DEF_MIN_R,
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|     .max_r = CAM_DEF_MAX_R,
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|     .min_i = ((double)RES_Y / RES_X) * CAM_DEF_MIN_R,
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|     .max_i = ((double)RES_Y / RES_X) * CAM_DEF_MAX_R,
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| 
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|   };
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|   static int view_mode = VIEW_UNINIT;
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|   static uint16_t colorscheme[ITERS];
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| 
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| 
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|   
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|   //we could get rid of this and do some awful bitbashing lol
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|   //but for readability, we shant
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|   //TODO camera moves l/r more then u/d for some reason
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|   /**
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|   if(key_pressed & CAM_MOVE_UP)    cam_shift(&cam, 0, STEP_SIZE);
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|   if(key_pressed & CAM_MOVE_DOWN)  cam_shift(&cam, 0, -STEP_SIZE);
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|   if(key_pressed & CAM_MOVE_RIGHT) cam_shift(&cam, -STEP_SIZE, 0);
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|   if(key_pressed & CAM_MOVE_LEFT)  cam_shift(&cam, STEP_SIZE, 0);
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|   if(key_pressed & CAM_ZOOM_IN)    cam_zoom(&cam, ZOOM_SIZE);
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|   if(key_pressed & CAM_ZOOM_OUT)   cam_zoom(&cam, -ZOOM_SIZE);
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|   **/
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|   
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|   //yes, I know the following is disgusting. Before I clean it, I just wanna get the general idea out, 
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|   //it's more efficient in that order
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|   //TODO once you  get your idea ironed out, clean the code and improve the flow
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|   benchmark_start();
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|   if(view_mode == VIEW_UNINIT) {
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|     view_mode = VIEW_MANDREL;
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|     init_colorscheme_mandrel(colorscheme);
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|     render_mandelbrot(framebuffer, colorscheme, cam, 0, 0, RES_X, RES_Y/2);
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|     ST7735_DrawImage(0, 0, RES_X, (RES_Y / 2), framebuffer);
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|     render_mandelbrot(framebuffer, colorscheme, cam, 0, RES_Y/2, RES_X, RES_Y/2);
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|     ST7735_DrawImage(0, (RES_Y / 2), RES_X, (RES_Y / 2), framebuffer);
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|     bottom_buffered = true;
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|   }
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|   else {
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|     uint16_t top_line = bottom_buffered ? (RES_Y/2) : 0; 
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|     switch(key_pressed) {
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|       const int y_offset = STEP_SIZE * RES_Y;
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|       const int x_offset = STEP_SIZE * RES_X;
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|       const size_t lines_rendered = (RES_Y/2) - y_offset;
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|       const size_t rendered_area_y = RES_X * lines_rendered * sizeof(uint16_t);
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|       const uint16_t framebuffer_offset_y = framebuffer + (RES_X * y_offset);
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|       const uint16_t columns_rendered = RES_X - x_offset;
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|       const uint16_t 
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|       case BUTTON_UP:
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|         cam_shift(&cam, 0, STEP_SIZE);
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|         memmove(framebuffer_offset, framebuffer, rendered_area_y);
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|         render_mandelbrot(framebuffer, colorscheme, cam, 0, top_line, RES_X, y_offset);
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|         break;
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|       case BUTTON_DOWN:
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|         cam_shift(&cam, 0, -STEP_SIZE);
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|         memmove(framebuffer, framebuffer_offset_y, rendered_area_y);
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|         render_mandelbrot(framebuffer+(RES_X*lines_rendered), colorscheme, cam, 0, bottom_buffered ? RES_Y : lines_rendered, RES_X, y_offset);
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|         break;
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|       case BUTTON_RIGHT:
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|         cam_shift(&cam, STEP_SIZE, 0);
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|         render_mandelbrot(columnbuffer, colorscheme, cam, RES_X - x_offset, top_line, x_offset, RES_Y/2);
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|         for(uint16_t y = 0; y < RES_Y/2; y++) {
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|           memmove(framebuffer + (RES_X * y), framebuffer + (RES_X * y) + x_offset, (RES_X - x_offset) * sizeof(*framebuffer));
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|           memmove(framebuffer + (RES_X * y) + (RES_X - x_offset), columnbuffer + (x_offset * y), x_offset * sizeof(*framebuffer));
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|         }
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|         break;
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|       case BUTTON_LEFT:
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|         cam_shift(&cam, -STEP_SIZE, 0);
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|         render_mandelbrot(columnbuffer, colorscheme, cam, 0, top_line, x_offset, RES_Y/2);
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|         for(uint16_t y = 0; y < RES_Y/2; y++) {
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|           memmove(framebuffer + (RES_X * y) + x_offset, framebuffer + (RES_X * y), (RES_X - x_offset) * sizeof(*framebuffer));
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|           memmove(framebuffer + (RES_X * y), columnbuffer + (x_offset * y), x_offset * sizeof(*framebuffer));
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|         }
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|         break;
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|       case BUTTON_A:
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|         cam_zoom(&cam, ZOOM_SIZE);
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|         render_mandelbrot(framebuffer, colorscheme, cam, 0, top_line, RES_X, RES_Y/2);
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|         break;
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|       case BUTTON_B:
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|         cam_zoom(&cam, -ZOOM_SIZE);
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|         render_mandelbrot(framebuffer, colorscheme, cam, 0, top_line, RES_X, RES_Y/2);
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|         break;
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|       default:
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|         render_mandelbrot(framebuffer, colorscheme, cam, 0, top_line, RES_X, RES_Y/2);
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|     }
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|    ST7735_DrawImage(0, top_line, RES_X, (RES_Y/2), framebuffer);
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| 
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|    bottom_buffered = !bottom_buffered;
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|    top_line = bottom_buffered ? (RES_Y/2) : 0; 
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|    render_mandelbrot(framebuffer, colorscheme, cam, 0, top_line, RES_X, RES_Y/2);
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|    ST7735_DrawImage(0, top_line, RES_X, (RES_Y/2), framebuffer);
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|   }
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|   benchmark_stop();
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| 
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| 
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|   /**
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|   render_mandelbrot(framebuffer, colorscheme, cam, false, key_pressed);
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|   ST7735_DrawImage(0, 0, ST7735_WIDTH, (ST7735_HEIGHT / 2), framebuffer);
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|   render_mandelbrot(framebuffer, colorscheme, cam, true, key_pressed);
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|   ST7735_DrawImage(0, (ST7735_HEIGHT / 2), ST7735_WIDTH, (ST7735_HEIGHT / 2), framebuffer);
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|   **/
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| //  ST7735_DrawImage(0, 0, ST7735_WIDTH - 1, ST7735_HEIGHT - 1, (uint16_t *)0x80000000);
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| }
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