Fixed border extension for the sunbeams node.

This ensures that the beams color does not darken along borders,
by using the last valid color of the ray as the border color (extending
colors in the direction of the source point).
This commit is contained in:
Lukas Tönne
2014-09-23 11:42:11 +02:00
parent d7ddb941a0
commit dbb9eba0fb
5 changed files with 21 additions and 14 deletions

2
scons

Submodule scons updated: 1ec93106c4...625d446ae8

View File

@@ -138,6 +138,7 @@ struct BufferLineAccumulator {
int x, y, num;
float v, dv;
float falloff_factor;
float border[4];
if ((int)pt_ofs[0] == 0 && (int)pt_ofs[1] == 0) {
copy_v4_v4(output, input->getBuffer() + COM_NUMBER_OF_CHANNELS * ((int)source[0] + input->getWidth() * (int)source[1]));
@@ -146,19 +147,26 @@ struct BufferLineAccumulator {
/* initialise the iteration variables */
float *buffer = init_buffer_iterator(input, source, pt_ofs, dist_min, dist_max, x, y, num, v, dv, falloff_factor);
int tot = 0;
zero_v3(border);
border[3] = 1.0f;
/* v_local keeps track of when to decrement v (see below) */
float v_local = v - floorf(v);
for (int i = 0; i < num; i++) {
/* range check, abort when running beyond the image border */
if (x < rect.xmin || x >= rect.xmax || y < rect.ymin || y >= rect.ymax)
break;
float f = 1.0f - (float)i * falloff_factor;
madd_v4_v4fl(output, buffer, buffer[3] * f * f);
float weight = 1.0f - (float)i * falloff_factor;
weight *= weight;
/* range check, use last valid color when running beyond the image border */
if (x >= rect.xmin && x < rect.xmax && y >= rect.ymin && y < rect.ymax) {
madd_v4_v4fl(output, buffer, buffer[3] * weight);
/* use as border color in case subsequent pixels are out of bounds */
copy_v4_v4(border, buffer);
}
else {
madd_v4_v4fl(output, border, border[3] * weight);
}
/* TODO implement proper filtering here, see
* http://en.wikipedia.org/wiki/Lanczos_resampling
* http://en.wikipedia.org/wiki/Sinc_function
@@ -166,9 +174,8 @@ struct BufferLineAccumulator {
* using lanczos with x = distance from the line segment,
* normalized to a == 0.5f, could give a good result
*
* for now just count samples and divide equally at the end ...
* for now just divide equally at the end ...
*/
tot++;
/* decrement u */
x -= fxx;