FloatImg/funcs/rampes.c

114 lines
2.3 KiB
C

/*
* FLOATIMG
* rampes diverses, trucs etranges
*/
#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <sys/time.h>
#include "../floatimg.h"
/* --------------------------------------------------------------------- */
int fimg_hdeg_a(FloatImg *img, double dcoef)
{
int x, y;
float value;
#if DEBUG_LEVEL
fprintf(stderr, ">>> %s ( %p %f )\n", __func__, img, dcoef);
#endif
if (FIMG_TYPE_RGB != img->type) {
fprintf(stderr, "%s bad type\n", __func__);
return -6;
}
for (x=0; x<img->width; x++) {
value = (float)x / (float)img->width;
value *= dcoef;
for (y=0; y<img->height; y++) {
fimg_plot_rgb(img, x, y, value, value, value);
}
}
return 0;
}
/* --------------------------------------------------------------------- */
/*
* To have the black at the bottom, use a negative dcoef
*/
int fimg_vdeg_a(FloatImg *img, double dcoef)
{
int x, y;
float value;
#if DEBUG_LEVEL
fprintf(stderr, ">>> %s ( %p %f )\n", __func__, img, dcoef);
#endif
if (FIMG_TYPE_RGB != img->type) {
fprintf(stderr, "%s bad type\n", __func__);
return -6;
}
for (x=0; x<img->width; x++) {
value = (float)x / (float)img->width;
value *= dcoef;
for (y=0; y<img->height; y++) {
fimg_plot_rgb(img, x, y, value, value, value);
}
}
return 0;
}
/* --------------------------------------------------------------------- */
/* nouveau 19 septembre 2022
*
* 6 octobre 2023 : rajout du parametre 'fmax'
*/
int fimg_do_stripes(FloatImg *img, float fmax, int mode)
{
int x, y, quad;
float *ligne;
float fr, fg, fb;
fprintf(stderr, ">>> %s ( %p %f %d )\n", __func__, img, fmax, mode);
/*
* allocate and fill a lookup table
*/
if (NULL==(ligne=malloc(img->width*sizeof(float)))) {
fprintf(stderr, "%s: malloc fail\n", __func__);
exit(1);
}
for (x=0; x<img->width; x++) {
ligne[x] = (float)x / (float)img->width;
ligne[x] *= fmax;
}
/*
* build the pixels
*/
for (y=0; y<img->height; y++)
{
quad = (y*4) / img->height ;
for (x=0; x<img->width; x++) {
fr = fg = fb = ligne[x];
switch(quad) {
case 0: fg = fb = 0; break;
case 1: fr = fb = 0; break;
case 2: fr = fg = 0; break;
case 3: break;
default: abort(); break;
}
fimg_plot_rgb(img, x, y, fr, fg, fb);
}
}
free(ligne);
return 0;
}
/* --------------------------------------------------------------------- */