Forgot to add blendmodes.c

Not functional yet.

2 files changed, 214 insertions, 1 deletions

diff --git a/raster/blendmodes.c b/raster/blendmodes.c
new file mode 100644
index 00000000..f3ba8ac5
--- /dev/null
+++ b/raster/blendmodes.c
@@ -0,0 +1,213 @@
+#include "fitz-base.h"
+#include "fitz-world.h"
+#include "fitz-draw.h"
+
+typedef unsigned char byte;
+
+/*
+PDF 1.4 blend modes, except Normal and Multiply which are Over and In respectively.
+Only the actual blend routines are here, not the node rendering logic which lives in render.c.
+These are slow.
+*/
+
+
+/* These functions apply to a single component, 0-255 range typically */
+
+static int
+fz_screen_byte(int bd, int s)
+{
+	return bd + s - fz_mul255(bd, s);
+}
+
+
+static int
+fz_hardlight_byte(int bd, int s)
+{
+	int s2 = s << 1;
+	if (s <= 127)
+		return fz_mul255(bd, s2);
+	else
+		return fz_screen_byte(bd, s2);
+}
+
+
+static int
+fz_overlay_byte(int bd, int s)
+{
+	return fz_hardlight_byte(s, bd); // note swapped order
+}
+
+
+static int
+fz_darken_byte(int bd, int s)
+{
+	return MIN(bd, s);
+}
+
+
+static int
+fz_lighten_byte(int bd, int s)
+{
+	return MAX(bd, s);
+}
+
+
+static int
+fz_colordodge_byte(int bd, int s)
+{
+	if (s < 255)
+		return MIN(255, 255 * bd / (255 - s));
+	else
+		return 255;
+}
+
+
+static int
+fz_colorburn_byte(int bd, int s)
+{
+	if (s > 0)
+		return 255 - MIN(255, 255 * (255 - bd) / s);
+	else
+		return 0;
+}
+
+
+static int
+fz_softlight_byte(int bd, int s)
+{
+	/* review this */
+	if (s < 128) {
+		return bd - fz_mul255(fz_mul255((255 - (s<<1)), bd), 255 - bd);
+	}
+	else {
+		int dbd;
+		if (bd < 64)
+			dbd = fz_mul255(fz_mul255((bd << 4) - 12, bd) + 4, bd);
+		else
+			dbd = (int)sqrtf(255.0f * bd);
+		return bd + fz_mul255(((s<<1) - 255), (dbd - bd));
+	}
+}
+
+
+static int
+fz_difference_byte(int bd, int s)
+{
+	return ABS(bd - s);
+}
+
+
+static int
+fz_exclusion_byte(int bd, int s)
+{
+	return bd + s - (fz_mul255(bd, s)<<1);
+}
+
+
+/* Non-separable blend modes */
+
+
+static int
+lum(int r, int g, int b)
+{
+	/* 0.3, 0.59, 0.11 in 16.16 fixed point */
+	return (19662 * r + 38666 * g + 7208 * b) >> 16;
+}
+
+
+static void
+clipcolor(int r, int g, int b, int *dr, int *dg, int *db)
+{
+	int l = lum(r, g, b);
+	int n = MIN(MIN(r, g), b);
+	int x = MAX(MAX(r, g), b);
+	if (n < 0) {
+		*dr = l + 255 * (r - l) / (l - n);
+		*dg = l + 255 * (g - l) / (l - n);
+		*db = l + 255 * (b - l) / (l - n);
+	}
+	else {
+		*dr = l + 255 * (255 - l) / (x - l);
+		*dg = l + 255 * (255 - l) / (x - l);
+		*db = l + 255 * (255 - l) / (x - l);
+	}
+}
+
+
+static void
+setlum(int r, int g, int b, int l, int *dr, int *dg, int *db)
+{
+	int d = 255 - lum(r, g, b);
+	clipcolor(r + d, g + d, b + d, dr, dg, db);
+}
+
+
+static int
+sat(int r, int g, int b)
+{
+	return MAX(MAX(r, g), b) - MIN(MIN(r, g), b);
+}
+
+
+static void
+setsat(int r, int g, int b, int s, int *dr, int *dg, int *db)
+{
+	int *m[3] = { &r, &g, &b }; /* min, med, max */
+	int *t;
+#define SWAP(a, b) (t = a, a = b, b = t)
+	if (*m[0] > *m[1])
+		SWAP(m[0], m[1]);
+	if (*m[0] > *m[2])
+		SWAP(m[0], m[2]);
+	if (*m[1] > *m[2])
+		SWAP(m[1], m[2]);
+
+	if (*m[2] > *m[0]) {
+		*m[1] = (*m[1] - *m[0]) * s / (*m[2] - *m[0]);
+		*m[2] = s;
+	}
+	else {
+		*m[1] = 0;
+		*m[2] = 0;
+	}
+	*dr = r;
+	*dg = g;
+	*db = b;
+}
+
+
+static void
+fz_hue_rgb(int *bdr, int *bdg, int *bdb, int sr, int sg, int sb)
+{
+	int tr, tg, tb;
+	setsat(sr, sg, sb, sat(*bdr, *bdg, *bdb), &tr, &tg, &tb);
+	setlum(tr, tg, tb, lum(*bdr, *bdg, *bdb), bdr, bdg, bdb);
+}
+
+
+static void
+fz_saturation_rgb(int *bdr, int *bdg, int *bdb, int sr, int sg, int sb)
+{
+	int tr, tg, tb;
+	setsat(*bdr, *bdg, *bdb, sat(sr, sg, sb), &tr, &tg, &tb);
+	setlum(tr, tg, tb, lum(*bdr, *bdg, *bdb), bdr, bdg, bdb);	
+}
+
+
+static void
+fz_color_rgb(int *bdr, int *bdg, int *bdb, int sr, int sg, int sb)
+{
+	setlum(sr, sg, sb, lum(*bdr, *bdg, *bdb), bdr, bdg, bdb);
+}
+
+
+static void
+fz_luminosity_rgb(int *bdr, int *bdg, int *bdb, int sr, int sg, int sb)
+{
+	setlum(*bdr, *bdg, *bdb, lum(sr, sg, sb), bdr, bdg, bdb);
+}
+
+
+//fz_separable_blend(, fz_blendkind mode)
+//{
+//}
diff --git a/raster/render.c b/raster/render.c
index a7c2e2f5..fc649469 100644
--- a/raster/render.c
+++ b/raster/render.c
@@ -198,7 +198,7 @@ renderpath(fz_renderer *gc, fz_pathnode *path, fz_matrix ctm)
 	if (path->paint == FZ_STROKE)
 	{
 		float lw = path->linewidth;
-		// Check for hairline
+		/* Check for hairline */
 		if (lw * expansion < 0.2) {
 			lw = 1.0f / expansion;
 		}