leanup: style, use 'const' where possible, and simplified blend funcs.

Much better to use small loops when doing complex operations over color elements
(any serious compiler will flatten them anyway), avoids (some!) stupid mistakes when
editing their code.

Also, use min/max funcs instead of lengthier 'if (foo < 0) foo = 0'.

1 files changed, 284 insertions, 597 deletions

diff --git a/source/blender/blenlib/intern/math_color_blend_inline.c b/source/blender/blenlib/intern/math_color_blend_inline.c
index 1985e061172..2522fe5f6c9 100644
--- a/source/blender/blenlib/intern/math_color_blend_inline.c
+++ b/source/blender/blenlib/intern/math_color_blend_inline.c
@@ -225,40 +225,22 @@ MINLINE void blend_color_add_alpha_byte(unsigned char dst[4], const unsigned cha
 
 MINLINE void blend_color_overlay_byte(unsigned char dst[4], unsigned const char src1[4], unsigned const char src2[4])
 {
-	const unsigned char fac = src2[3];
+	const int fac = (int)src2[3];
 	if (fac != 0) {
-		int temp;
-		int mfac = 255 - fac;
-		if (src1[0] > 127)
-			temp = 255 - ((255 - 2 * (src1[0] - 127)) * (255 - src2[0]) / 255);
-		else
-			temp = (2 * src1[0] * src2[0]) >> 8;
-		temp = (temp * fac + src1[0] * mfac) / 255;
-		if (temp < 255)
-			dst[0] = temp;
-		else
-			dst[0] = 255;
-		if (src1[1] > 127)
-			temp = 255 - ((255 - 2 * (src1[1] - 127)) * (255 - src2[1]) / 255);
-		else
-			temp = (2 * src1[1] * src2[1]) / 255;
-
-		temp = (temp * fac + src1[1] * mfac) / 255;
-		if (temp < 255)
-			dst[1] = temp;
-		else
-			dst[1] = 255;
-
-		if (src1[2] > 127)
-			temp = 255 - ((255 - 2 * (src1[2] - 127)) * (255 - src2[2]) / 255);
-		else
-			temp = (2 * src1[2] * src2[2]) / 255;
-
-		temp = (temp * fac + src1[2] * mfac) / 255;
-		if (temp < 255)
-			dst[2] = temp;
-		else
-			dst[2] = 255;
+		const int mfac = 255 - fac;
+		int i = 3;
+
+		while (i--) {
+			int temp;
+
+			if (src1[i] > 127) {
+				temp = 255 - ((255 - 2 * (src1[i] - 127)) * (255 - src2[i]) / 255);
+			}
+			else {
+				temp = (2 * src1[i] * src2[i]) >> 8;
+			}
+			dst[i] = (unsigned char)min_ii((temp * fac + src1[i] * mfac) / 255, 255);
+		}
 	}
 	else {
 		/* no op */
@@ -269,33 +251,22 @@ MINLINE void blend_color_overlay_byte(unsigned char dst[4], unsigned const char
 
 MINLINE void blend_color_hardlight_byte(unsigned char dst[4], unsigned const char src1[4], unsigned const char src2[4])
 {
-	const unsigned char fac = src2[3];
+	const int fac = (int)src2[3];
 	if (fac != 0) {
-		int temp;
-		int mfac = 255 - fac;
-		if (src2[0] > 127)
-			temp = 255 - ((255 - 2 * (src2[0] - 127)) * (255 - src1[0]) / 255);
-		else
-			temp = (2 * src2[0] * src1[0]) >> 8;
-		temp = (temp * fac + src1[0] * mfac) / 255;
-		if (temp < 255) dst[0] = temp; else dst[0] = 255;
-
-
-		if (src2[1] > 127)
-			temp = 255 - ((255 - 2 * (src2[1] - 127)) * (255 - src1[1]) / 255);
-		else
-			temp = (2 * src2[1] * src1[1]) / 255;
-		temp = (temp * fac + src1[1] * mfac) / 255;
-		if (temp < 255) dst[1] = temp; else dst[1] = 255;
-
-
-		if (src2[2] > 127)
-			temp = 255 - ((255 - 2 * (src2[2] - 127)) * (255 - src1[2]) / 255);
-		else
-			temp = (2 * src2[2] * src1[2]) / 255;
-
-		temp = (temp * fac + src1[2] * mfac) / 255;
-		if (temp < 255) dst[2] = temp; else dst[2] = 255;
+		const int mfac = 255 - fac;
+		int i = 3;
+
+		while (i--) {
+			int temp;
+
+			if (src2[i] > 127) {
+				temp = 255 - ((255 - 2 * (src2[i] - 127)) * (255 - src1[i]) / 255);
+			}
+			else {
+				temp = (2 * src2[i] * src1[i]) >> 8;
+			}
+			dst[i] = (unsigned char)min_ii((temp * fac + src1[i] * mfac) / 255, 255);
+		}
 	}
 	else {
 		/* no op */
@@ -306,38 +277,15 @@ MINLINE void blend_color_hardlight_byte(unsigned char dst[4], unsigned const cha
 
 MINLINE void blend_color_burn_byte(unsigned char dst[4], unsigned const char src1[4], unsigned const char src2[4])
 {
-	const unsigned char fac = src2[3];
+	const int fac = src2[3];
 	if (fac != 0) {
-		int temp;
-		int mfac = 255 - fac;
-
-
-		if (src2[0] == 0)
-			temp = 0;
-		else
-			temp = 255 - ((255 - src1[0]) * 255) / src2[0];
-		if (temp < 0)
-			temp = 0;
-		dst[0] = (temp * fac + src1[0] * mfac) / 255;
-
-
-		if (src2[1] == 0)
-			temp = 0;
-		else
-			temp = 255 - ((255 - src1[1]) * 255) / src2[1];
-		if (temp < 0)
-			temp = 0;
-		dst[1] = (temp * fac + src1[1] * mfac) / 255;
-
-
-		if (src2[2] == 0)
-			temp = 0;
-		else
-			temp = 255 - ((255 - src1[2]) * 255) / src2[2];
-		if (temp < 0)
-			temp = 0;
-		dst[2] = (temp * fac + src1[2] * mfac) / 255;
+		const int mfac = 255 - fac;
+		int i = 3;
 
+		while (i--) {
+			const int temp = (src2[i] == 0) ? 0 : max_ii(255 - ((255 - src1[i]) * 255) / src2[i], 0);
+			dst[i] = (unsigned char)((temp * fac + src1[i] * mfac) / 255);
+		}
 	}
 	else {
 		/* no op */
@@ -348,22 +296,15 @@ MINLINE void blend_color_burn_byte(unsigned char dst[4], unsigned const char src
 
 MINLINE void blend_color_linearburn_byte(unsigned char dst[4], unsigned const char src1[4], unsigned const char src2[4])
 {
-	const unsigned char fac = src2[3];
+	const int fac = src2[3];
 	if (fac != 0) {
-		int temp;
-		int mfac = 255 - fac;
-
-		temp = src1[0] + src2[0] - 255;
-		if (temp < 0) temp = 0;
-		dst[0] = (temp * fac + src1[0] * mfac) / 255;
+		const int mfac = 255 - fac;
+		int i = 3;
 
-		temp = src1[1] + src2[1] - 255;
-		if (temp < 0) temp = 0;
-		dst[1] = (temp * fac + src1[1] * mfac) / 255;
-
-		temp = src1[2] + src2[2] - 255;
-		if (temp < 0) temp = 0;
-		dst[2] = (temp * fac + src1[2] * mfac) / 255;
+		while (i--) {
+			const int temp = max_ii(src1[i] + src2[i] - 255, 0);
+			dst[i] = (unsigned char)((temp * fac + src1[i] * mfac) / 255);
+		}
 	}
 	else {
 		/* no op */
@@ -374,25 +315,15 @@ MINLINE void blend_color_linearburn_byte(unsigned char dst[4], unsigned const ch
 
 MINLINE void blend_color_dodge_byte(unsigned char dst[4], unsigned const char src1[4], unsigned const char src2[4])
 {
-	const unsigned char fac = src2[3];
+	const int fac = src2[3];
 	if (fac != 0) {
-		int temp;
-		int mfac = 255 - fac;
+		const int mfac = 255 - fac;
+		int i = 3;
 
-		if (src2[0] == 255) temp = 255;
-		else temp = (src1[0] * 255) / (255 - src2[0]);
-		if (temp > 255) temp = 255;
-		dst[0] = (temp * fac + src1[0] * mfac) / 255;
-
-		if (src2[1] == 255) temp = 255;
-		else temp = (src1[1] * 255) / (255 - src2[1]);
-		if (temp > 255) temp = 255;
-		dst[1] = (temp * fac + src1[1] * mfac) / 255;
-
-		if (src2[2] == 255) temp = 255;
-		else temp = (src1[2] * 255) / (255 - src2[2]);
-		if (temp > 255) temp = 255;
-		dst[2] = (temp * fac + src1[2] * mfac) / 255;
+		while (i--) {
+			const int temp = (src2[i] == 255) ? 255 : min_ii((src1[i] * 255) / (255 - src2[i]), 255);
+			dst[i] = (unsigned char)((temp * fac + src1[i] * mfac) / 255);
+		}
 	}
 	else {
 		/* no op */
@@ -402,22 +333,15 @@ MINLINE void blend_color_dodge_byte(unsigned char dst[4], unsigned const char sr
 
 MINLINE void blend_color_screen_byte(unsigned char dst[4], unsigned const char src1[4], unsigned const char src2[4])
 {
-	const unsigned char fac = src2[3];
+	const int fac = src2[3];
 	if (fac != 0) {
-		int temp;
-		int mfac = 255 - fac;
-
-		temp = 255 - (((255 - src1[0]) * (255 - src2[0])) / 255);
-		if (temp < 0) temp = 0;
-		dst[0] = (temp * fac + src1[0] * mfac) / 255;
+		const int mfac = 255 - fac;
+		int i = 3;
 
-		temp = 255 - (((255 - src1[1]) * (255 - src2[1])) / 255);
-		if (temp < 0) temp = 0;
-		dst[1] = (temp * fac + src1[1] * mfac) / 255;
-
-		temp = 255 - (((255 - src1[2]) * (255 - src2[2])) / 255);
-		if (temp < 0) temp = 0;
-		dst[2] = (temp * fac + src1[2] * mfac) / 255;
+		while (i--) {
+			const int temp = max_ii(255 - (((255 - src1[i]) * (255 - src2[i])) / 255), 0);
+			dst[i] = (unsigned char)((temp * fac + src1[i] * mfac) / 255);
+		}
 	}
 	else {
 		/* no op */
@@ -428,19 +352,22 @@ MINLINE void blend_color_screen_byte(unsigned char dst[4], unsigned const char s
 
 MINLINE void blend_color_softlight_byte(unsigned char dst[4], unsigned const char src1[4], unsigned const char src2[4])
 {
-	const unsigned char fac = src2[3];
+	const int fac = src2[3];
 	if (fac != 0) {
-		int temp;
-		int mfac = 255 - fac;
-
-		temp = ((unsigned char)((src1[0] < 127) ? ((2 * ((src2[0] / 2) + 64)) * (src1[0])) / 255 : (255 - (2 * (255 - ((src2[0] / 2) + 64)) * (255 - src1[0]) / 255))));
-		dst[0] = (temp * fac + src1[0] * mfac) / 255;
-
-		temp = ((unsigned char)((src1[1] < 127) ? ((2 * ((src2[1] / 2) + 64)) * (src1[1])) / 255 : (255 - (2 * (255 - ((src2[1] / 2) + 64)) * (255 - src1[1]) / 255))));
-		dst[1] = (temp * fac + src1[1] * mfac) / 255;
-
-		temp = ((unsigned char)((src1[2] < 127) ? ((2 * ((src2[2] / 2) + 64)) * (src1[2])) / 255 : (255 - (2 * (255 - ((src2[2] / 2) + 64)) * (255 - src1[2]) / 255))));
-		dst[2] = (temp * fac + src1[2] * mfac) / 255;
+		const int mfac = 255 - fac;
+		int i = 3;
+
+		while (i--) {
+			int temp;
+
+			if (src1[i] < 127) {
+				temp = ((2 * ((src2[i] / 2) + 64)) * src1[i]) / 255;
+			}
+			else {
+				temp = 255 - (2 * (255 - ((src2[i] / 2) + 64)) * (255 - src1[i]) / 255);
+			}
+			dst[i] = (unsigned char)((temp * fac + src1[i] * mfac) / 255);
+		}
 	}
 	else {
 		/* no op */
@@ -451,46 +378,22 @@ MINLINE void blend_color_softlight_byte(unsigned char dst[4], unsigned const cha
 
 MINLINE void blend_color_pinlight_byte(unsigned char dst[4], unsigned const char src1[4], unsigned const char src2[4])
 {
-	const unsigned char fac = src2[3];
+	const int fac = src2[3];
 	if (fac != 0) {
-		int temp;
-		int mfac = 255 - fac;
-
-		if (src2[0] > 127) {
-			temp = 2 * (src2[0] - 127);
-			if (src1[0] > temp)
-				temp = src1[0];
-		}
-		else {
-			temp = 2 * src2[0];
-			if (src1[0] < temp)
-				temp = src1[0];
-		}
-
-		dst[0] = (temp * fac + src1[0] * mfac) / 255;
-
-
-		if (src2[1] > 127) {
-			temp = 2 * (src2[1] - 127);
-			if (src1[1] > temp) temp = src1[1];
+		const int mfac = 255 - fac;
+		int i = 3;
+
+		while (i--) {
+			int temp;
+
+			if (src2[i] > 127) {
+				temp = max_ii(2 * (src2[i] - 127), src1[i]);
+			}
+			else {
+				temp = min_ii(2 * src2[i], src1[i]);
+			}
+			dst[i] = (unsigned char)((temp * fac + src1[i] * mfac) / 255);
 		}
-		else {
-			temp = 2 * src2[1];
-			if (src1[1] < temp) temp = src1[1];
-		}
-
-		dst[1] = (temp * fac + src1[1] * mfac) / 255;
-
-
-		if (src2[2] > 127) {
-			temp = 2 * (src2[2] - 127);
-			if (src1[2] > temp) temp = src1[2];
-		}
-		else {
-			temp = 2 * src2[2];
-			if (src1[2] < temp) temp = src1[2];
-		}
-		dst[2] = (temp * fac + src1[2] * mfac) / 255;
 	}
 	else {
 		/* no op */
@@ -501,43 +404,22 @@ MINLINE void blend_color_pinlight_byte(unsigned char dst[4], unsigned const char
 
 MINLINE void blend_color_linearlight_byte(unsigned char dst[4], unsigned const char src1[4], unsigned const char src2[4])
 {
-	const unsigned char fac = src2[3];
+	const int fac = src2[3];
 	if (fac != 0) {
-		int temp;
-		int mfac = 255 - fac;
-
-		if (src2[0] > 127) {
-			temp = src1[0] + 2 * (src2[0] - 127);
-			if (temp > 255)
-				temp = 255;
-		}
-		else {
-			temp = src1[0] + 2 * src2[0] - 255;
-			if (temp < 0) temp = 0;
-		}
-		dst[0] = (temp * fac + src1[0] * mfac) / 255;
-
-		if (src2[1] > 127) {
-			temp = src1[1] + 2 * (src2[1] - 127);
-			if (temp > 255)
-				temp = 255;
-		}
-		else {
-			temp = src1[1] + 2 * src2[1] - 255;
-			if (temp < 0) temp = 0;
-		}
-		dst[1] = (temp * fac + src1[1] * mfac) / 255;
-
-		if (src2[2] > 127) {
-			temp = src1[2] + 2 * (src2[2] - 127);
-			if (temp > 255)
-				temp = 255;
+		const int mfac = 255 - fac;
+		int i = 3;
+
+		while (i--) {
+			int temp;
+
+			if (src2[i] > 127) {
+				temp = min_ii(src1[i] + 2 * (src2[i] - 127), 255);
+			}
+			else {
+				temp = max_ii(src1[i] + 2 * src2[i] - 255, 0);
+			}
+			dst[i] = (unsigned char)((temp * fac + src1[i] * mfac) / 255);
 		}
-		else {
-			temp = src1[2] + 2 * src2[2] - 255;
-			if (temp < 0) temp = 0;
-		}
-		dst[2] = (temp * fac + src1[2] * mfac) / 255;
 	}
 	else {
 		/* no op */
@@ -548,55 +430,28 @@ MINLINE void blend_color_linearlight_byte(unsigned char dst[4], unsigned const c
 
 MINLINE void blend_color_vividlight_byte(unsigned char dst[4], unsigned const char src1[4], unsigned const char src2[4])
 {
-	const unsigned char fac = src2[3];
+	const int fac = src2[3];
 	if (fac != 0) {
-		int temp;
-		int mfac = 255 - fac;
-
-		if (src2[0] == 255)
-			temp = 255;
-		else if (src2[0] == 0)
-			temp = 0;
-		else if (src2[0] > 127)  {
-			temp = ((src1[0]) * 255) / (2 * (255 - src2[0]));
-			if (temp > 255) temp = 255;
-		}
-		else {
-			temp = 255 - ((255 - src1[0]) * 255 / (2 * src2[0]));
-			if (temp < 0) temp = 0;
-		}
-
-		dst[0] = (temp * fac + src1[0] * mfac) / 255;
+		const int mfac = 255 - fac;
+		int i = 3;
 
-		if (src2[1] == 255)
-			temp = 255;
-		else if (src2[1] == 0)
-			temp = 0;
-		else if (src2[1] > 127)  {
-			temp = ((src1[1]) * 255) / (2 * (255 - src2[1]));
-			if (temp > 255) temp = 255;
-		}
-		else {
-			temp = 255 - ((255 - src1[1]) * 255 / (2 * src2[1]));
-			if (temp < 0) temp = 0;
-		}
+		while (i--) {
+			int temp;
 
-		dst[1] = (temp * fac + src1[1] * mfac) / 255;
-
-		if (src2[2] == 255)
-			temp = 255;
-		else if (src2[2] == 0)
-			temp = 0;
-		else if (src2[2] > 127)  {
-			temp = ((src1[2]) * 255) / (2 * (255 - src2[2]));
-			if (temp > 255) temp = 255;
-		}
-		else {
-			temp = 255 - ((255 - src1[2]) * 255 / (2 * src2[2]));
-			if (temp < 0) temp = 0;
+			if (src2[i] == 255) {
+				temp = 255;
+			}
+			else if (src2[i] == 0) {
+				temp = 0;
+			}
+			else if (src2[i] > 127)  {
+				temp = min_ii(((src1[i]) * 255) / (2 * (255 - src2[i])), 255);
+			}
+			else {
+				temp = max_ii(255 - ((255 - src1[i]) * 255 / (2 * src2[i])), 0);
+			}
+			dst[i] = (unsigned char)((temp * fac + src1[i] * mfac) / 255);
 		}
-
-		dst[2] = (temp * fac + src1[2] * mfac) / 255;
 	}
 	else {
 		/* no op */
@@ -608,22 +463,15 @@ MINLINE void blend_color_vividlight_byte(unsigned char dst[4], unsigned const ch
 
 MINLINE void blend_color_difference_byte(unsigned char dst[4], unsigned const char src1[4], unsigned const char src2[4])
 {
-	const unsigned char fac = src2[3];
+	const int fac = src2[3];
 	if (fac != 0) {
-		int temp;
-		int mfac = 255 - fac;
-		temp = src1[0] - src2[0];
-		if (temp < 0) temp = -temp;
-		dst[0] = (temp * fac + src1[0] * mfac) / 255;
-
-		temp = src1[1] - src2[1];
-		if (temp < 0) temp = -temp;
-		dst[1] = (temp * fac + src1[1] * mfac) / 255;
-
-		temp = src1[2] - src2[2];
-		if (temp < 0) temp = -temp;
-		dst[2] = (temp * fac + src1[2] * mfac) / 255;
+		const int mfac = 255 - fac;
+		int i = 3;
 
+		while (i--) {
+			const int temp = abs(src1[i] - src2[i]);
+			dst[i] = (unsigned char)((temp * fac + src1[i] * mfac) / 255);
+		}
 	}
 	else {
 		/* no op */
@@ -634,18 +482,15 @@ MINLINE void blend_color_difference_byte(unsigned char dst[4], unsigned const ch
 
 MINLINE void blend_color_exclusion_byte(unsigned char dst[4], unsigned const char src1[4], unsigned const char src2[4])
 {
-	const unsigned char fac = src2[3];
+	const int fac = src2[3];
 	if (fac != 0) {
-		int temp;
-		int mfac = 255 - fac;
-		temp = 127 - ((2 * (src1[0] - 127) * (src2[0] - 127)) / 255);
-		dst[0] = (temp * fac + src1[0] * mfac) / 255;
-
-		temp = 127 - ((2 * (src1[1] - 127) * (src2[1] - 127)) / 255);
-		dst[1] = (temp * fac + src1[1] * mfac) / 255;
+		const int mfac = 255 - fac;
+		int i = 3;
 
-		temp = 127 - ((2 * (src1[2] - 127) * (src2[2] - 127)) / 255);
-		dst[2] = (temp * fac + src1[2] * mfac) / 255;
+		while (i--) {
+			const int temp = 127 - ((2 * (src1[i] - 127) * (src2[i] - 127)) / 255);
+			dst[i] = (unsigned char)((temp * fac + src1[i] * mfac) / 255);
+		}
 	}
 	else {
 		/* no op */
@@ -655,9 +500,9 @@ MINLINE void blend_color_exclusion_byte(unsigned char dst[4], unsigned const cha
 
 MINLINE void blend_color_color_byte(unsigned char dst[4], unsigned const char src1[4], unsigned const char src2[4])
 {
-	const unsigned char fac = src2[3];
+	const int fac = src2[3];
 	if (fac != 0) {
-		int mfac = 255 - fac;
+		const int mfac = 255 - fac;
 		float h1, s1, v1;
 		float h2, s2, v2;
 		float r, g, b;
@@ -670,9 +515,9 @@ MINLINE void blend_color_color_byte(unsigned char dst[4], unsigned const char sr
 
 		hsv_to_rgb(h1, s1, v1, &r, &g, &b);
 
-		dst[0] = ((int)(r * 255.0f) * fac + src1[0] * mfac) / 255;
-		dst[1] = ((int)(g * 255.0f) * fac + src1[1] * mfac) / 255;
-		dst[2] = ((int)(b * 255.0f) * fac + src1[2] * mfac) / 255;
+		dst[0] = (unsigned char)(((int)(r * 255.0f) * fac + src1[0] * mfac) / 255);
+		dst[1] = (unsigned char)(((int)(g * 255.0f) * fac + src1[1] * mfac) / 255);
+		dst[2] = (unsigned char)(((int)(b * 255.0f) * fac + src1[2] * mfac) / 255);
 	}
 	else {
 		/* no op */
@@ -682,9 +527,9 @@ MINLINE void blend_color_color_byte(unsigned char dst[4], unsigned const char sr
 
 MINLINE void blend_color_hue_byte(unsigned char dst[4], unsigned const char src1[4], unsigned const char src2[4])
 {
-	const unsigned char fac = src2[3];
+	const int fac = src2[3];
 	if (fac != 0) {
-		int mfac = 255 - fac;
+		const int mfac = 255 - fac;
 		float h1, s1, v1;
 		float h2, s2, v2;
 		float r, g, b;
@@ -696,9 +541,9 @@ MINLINE void blend_color_hue_byte(unsigned char dst[4], unsigned const char src1
 
 		hsv_to_rgb(h1, s1, v1, &r, &g, &b);
 
-		dst[0] = ((int)(r * 255.0f) * fac + src1[0] * mfac) / 255;
-		dst[1] = ((int)(g * 255.0f) * fac + src1[1] * mfac) / 255;
-		dst[2] = ((int)(b * 255.0f) * fac + src1[2] * mfac) / 255;
+		dst[0] = (unsigned char)(((int)(r * 255.0f) * fac + src1[0] * mfac) / 255);
+		dst[1] = (unsigned char)(((int)(g * 255.0f) * fac + src1[1] * mfac) / 255);
+		dst[2] = (unsigned char)(((int)(b * 255.0f) * fac + src1[2] * mfac) / 255);
 	}
 	else {
 		/* no op */
@@ -709,9 +554,9 @@ MINLINE void blend_color_hue_byte(unsigned char dst[4], unsigned const char src1
 
 MINLINE void blend_color_saturation_byte(unsigned char dst[4], unsigned const char src1[4], unsigned const char src2[4])
 {
-	const unsigned char fac = src2[3];
+	const int fac = src2[3];
 	if (fac != 0) {
-		int mfac = 255 - fac;
+		const int mfac = 255 - fac;
 		float h1, s1, v1;
 		float h2, s2, v2;
 		float r, g, b;
@@ -724,9 +569,9 @@ MINLINE void blend_color_saturation_byte(unsigned char dst[4], unsigned const ch
 
 		hsv_to_rgb(h1, s1, v1, &r, &g, &b);
 
-		dst[0] = ((int)(r * 255.0f) * fac + src1[0] * mfac) / 255;
-		dst[1] = ((int)(g * 255.0f) * fac + src1[1] * mfac) / 255;
-		dst[2] = ((int)(b * 255.0f) * fac + src1[2] * mfac) / 255;
+		dst[0] = (unsigned char)(((int)(r * 255.0f) * fac + src1[0] * mfac) / 255);
+		dst[1] = (unsigned char)(((int)(g * 255.0f) * fac + src1[1] * mfac) / 255);
+		dst[2] = (unsigned char)(((int)(b * 255.0f) * fac + src1[2] * mfac) / 255);
 	}
 	else {
 		/* no op */
@@ -736,23 +581,22 @@ MINLINE void blend_color_saturation_byte(unsigned char dst[4], unsigned const ch
 
 MINLINE void blend_color_luminosity_byte(unsigned char dst[4], unsigned const char src1[4], unsigned const char src2[4])
 {
-	const unsigned char fac = src2[3];
+	const int fac = src2[3];
 	if (fac != 0) {
-		int mfac = 255 - fac;
+		const int mfac = 255 - fac;
 		float h1, s1, v1;
 		float h2, s2, v2;
 		float r, g, b;
 		rgb_to_hsv(src1[0] / 255.0f, src1[1] / 255.0f, src1[2] / 255.0f, &h1, &s1, &v1);
 		rgb_to_hsv(src2[0] / 255.0f, src2[1] / 255.0f, src2[2] / 255.0f, &h2, &s2, &v2);
 
-
 		v1 = v2;
 
 		hsv_to_rgb(h1, s1, v1, &r, &g, &b);
 
-		dst[0] = ((int)(r * 255.0f) * fac + src1[0] * mfac) / 255;
-		dst[1] = ((int)(g * 255.0f) * fac + src1[1] * mfac) / 255;
-		dst[2] = ((int)(b * 255.0f) * fac + src1[2] * mfac) / 255;
+		dst[0] = (unsigned char)(((int)(r * 255.0f) * fac + src1[0] * mfac) / 255);
+		dst[1] = (unsigned char)(((int)(g * 255.0f) * fac + src1[1] * mfac) / 255);
+		dst[2] = (unsigned char)(((int)(b * 255.0f) * fac + src1[2] * mfac) / 255);
 
 	}
 	else {
@@ -939,43 +783,22 @@ MINLINE void blend_color_add_alpha_float(float dst[4], const float src1[4], cons
 
 MINLINE void blend_color_overlay_float(float dst[3], const float src1[3], const float src2[3])
 {
-	float fac = src2[3];
+	const float fac = src2[3];
 	if (fac != 0.0f && fac < 1.0f) {
-
-		float temp;
-		float fac = src2[3];
-		float mfac = 1.0f - fac;
-
-		if (src1[0] > 0.5f)
-			temp = 1 - (1 - 2 * (src1[0] - 0.5f)) * (1 - src2[0]);
-		else
-			temp = 2 * src1[0] * src2[0];
-		temp = temp * fac + src1[0] * mfac;
-		if (temp < 1.0f)
-			dst[0] = temp;
-		else
-			dst[0] = 1.0f;
-
-
-		if (src1[1] > 0.5f)
-			temp = 1.0f - (1.0f - 2.0f * (src1[1] - 0.5f)) * (1.0f - src2[1]);
-		else
-			temp = 2.0f * src1[1] * src2[1];
-		temp = temp * fac + src1[1] * mfac;
-		if (temp < 1.0f)
-			dst[1] = temp;
-		else
-			dst[1] = 1.0f;
-
-		if (src1[2] > 0.5f)
-			temp = 1 - (1.0f - 2.0f * (src1[2] - 0.5f)) * (1.0f - src2[2]);
-		else
-			temp = 2.0f * src1[2] * src2[2];
-		temp = temp * fac + src1[2] * mfac;
-		if (temp < 1.0f)
-			dst[2] = temp;
-		else
-			dst[2] = 1.0f;
+		const float mfac = 1.0f - fac;
+		int i = 3;
+
+		while (i--) {
+			float temp;
+
+			if (src1[i] > 0.5f) {
+				temp = 1.0f - (1.0f - 2.0f * (src1[i] - 0.5f)) * (1.0f - src2[i]);
+			}
+			else {
+				temp = 2.0f * src1[i] * src2[i];
+			}
+			dst[i] = min_ff(temp * fac + src1[i] * mfac, 1.0f);
+		}
 	}
 	else {
 		/* no op */
@@ -988,33 +811,20 @@ MINLINE void blend_color_hardlight_float(float dst[4], const float src1[4], cons
 {
 	const float fac = src2[3];
 	if (fac != 0.0f && fac < 1.0f) {
-		float temp;
-		float mfac = 1.0f - fac;
-		if (src2[0] > 0.5f)
-			temp = 1 - ((1.0f - 2.0f * (src2[0] - 0.5f)) * (1.0f - src1[0]));
-		else
-			temp = 2.0f * src2[0] * src1[0];
-		temp = (temp * fac + src1[0] * mfac) / 1.0f;
-		if (temp < 1.0f) dst[0] = temp; else dst[0] = 1.0f;
-
-		if (src2[1] > 0.5f)
-			temp = 1 - ((1.0f - 2.0f * (src2[1] - 0.5f)) * (1.0f - src1[1]));
-		else
-			temp = 2.0f * src2[1] * src1[1];
-		temp = (temp * fac + src1[1] * mfac) / 1.0f;
-		if (temp < 1.0f) dst[1] = temp; else dst[1] = 1.0f;
-
-		if (src2[2] > 0.5f)
-			temp = 1 - ((1.0f - 2.0f * (src2[2] - 0.5f)) * (1.0f - src1[2]));
-		else
-			temp = 2.0f * src2[2] * src1[2];
-		temp = (temp * fac + src1[2] * mfac) / 1.0f;
-
-		if (temp < 1.0f)
-			dst[2] = temp;
-		else
-			dst[2] = 1.0f;
-
+		const float mfac = 1.0f - fac;
+		int i = 3;
+
+		while (i--) {
+			float temp;
+
+			if (src2[i] > 0.5f) {
+				temp = 1.0f - ((1.0f - 2.0f * (src2[i] - 0.5f)) * (1.0f - src1[i]));
+			}
+			else {
+				temp = 2.0f * src2[i] * src1[i];
+			}
+			dst[i] = min_ff((temp * fac + src1[i] * mfac) / 1.0f, 1.0f);
+		}
 	}
 	else {
 		/* no op */
@@ -1026,32 +836,13 @@ MINLINE void blend_color_burn_float(float dst[3], const float src1[3], const flo
 {
 	const float fac = src2[3];
 	if (fac != 0.0f && fac < 1.0f) {
-		float temp;
-		float mfac = 1.0f - fac;
-
-		if (src2[0] == 0.0f)
-			temp = 0.0f;
-		else
-			temp = 1.0f - ((1.0f - src1[0]) / src2[0]);
-		if (temp < 0.0f)
-			temp = 0.0f;
-		dst[0] = (temp * fac + src1[0] * mfac);
-
-		if (src2[1] == 0.0f)
-			temp = 0.0f;
-		else
-			temp = 1.0f - ((1.0f - src1[1]) / src2[1]);
-		if (temp < 0.0f)
-			temp = 0.0f;
-		dst[1] = (temp * fac + src1[1] * mfac);
-
-		if (src2[2] == 0.0f)
-			temp = 0.0f;
-		else
-			temp = 1.0f - ((1.0f - src1[2]) / src2[2]);
-		if (temp < 0.0f)
-			temp = 0.0f;
-		dst[2] = (temp * fac + src1[2] * mfac);
+		const float mfac = 1.0f - fac;
+		int i = 3;
+
+		while (i--) {
+			const float temp = (src2[i] == 0.0f) ? 0.0f : max_ff(1.0f - ((1.0f - src1[i]) / src2[i]), 0.0f);
+			dst[i] = (temp * fac + src1[i] * mfac);
+		}
 	}
 	else {
 		/* no op */
@@ -1063,21 +854,13 @@ MINLINE void blend_color_linearburn_float(float dst[3], const float src1[3], con
 {
 	const float fac = src2[3];
 	if (fac != 0.0f && fac < 1.0f) {
-		float temp;
-		float mfac = 1.0f - fac;
-
-		temp = src1[0] + src2[0] - 1.0f;
-		if (temp < 0) temp = 0;
-		dst[0] = (temp * fac + src1[0] * mfac);
-
-		temp = src1[1] + src2[1] - 1.0f;
-		if (temp < 0) temp = 0;
-		dst[1] = (temp * fac + src1[1] * mfac);
-
-		temp = src1[2] + src2[2] - 1.0f;
-		if (temp < 0) temp = 0;
-		dst[2] = (temp * fac + src1[2] * mfac);
+		const float mfac = 1.0f - fac;
+		int i = 3;
 
+		while (i--) {
+			const float temp = max_ff(src1[i] + src2[i] - 1.0f, 0.0f);
+			dst[i] = (temp * fac + src1[i] * mfac);
+		}
 	}
 	else {
 		/* no op */
@@ -1090,23 +873,13 @@ MINLINE void blend_color_dodge_float(float dst[3], const float src1[3], const fl
 {
 	const float fac = src2[3];
 	if (fac != 0.0f && fac < 1.0f) {
-		float temp;
-		float mfac = 1.0f - fac;
-
-		if (src2[0] >= 1.0f) temp = 1.0f;
-		else temp = (src1[0]) / (1.0f - src2[0]);
-		if (temp > 1.0f) temp = 1.0f;
-		dst[0] = (temp * fac + src1[0] * mfac);
-
-		if (src2[1] >= 1.0f) temp = 1.0f;
-		else temp = (src1[1]) / (1.0f - src2[1]);
-		if (temp > 1.0f) temp = 1.0f;
-		dst[1] = (temp * fac + src1[1] * mfac);
+		const float mfac = 1.0f - fac;
+		int i = 3;
 
-		if (src2[2] >= 1.0f) temp = 1.0f;
-		else temp = (src1[2]) / (1.0f - src2[2]);
-		if (temp > 1.0f) temp = 1.0f;
-		dst[2] = (temp * fac + src1[2] * mfac);
+		while (i--) {
+			const float temp = (src2[i] >= 1.0f) ? 1.0f : min_ff(src1[i] / (1.0f - src2[i]), 1.0f);
+			dst[i] = (temp * fac + src1[i] * mfac);
+		}
 	}
 	else {
 		/* no op */
@@ -1118,20 +891,13 @@ MINLINE void blend_color_screen_float(float dst[3], const float src1[3], const f
 {
 	const float fac = src2[3];
 	if (fac != 0.0f && fac < 1.0f) {
-		float temp;
-		float mfac = 1.0f - fac;
-
-		temp = 1.0f - ((1.0f - src1[0]) * (1.0f - src2[0]));
-		if (temp < 0) temp = 0;
-		dst[0] = (temp * fac + src1[0] * mfac);
+		const float mfac = 1.0f - fac;
+		int i = 3;
 
-		temp = 1.0f - ((1.0f - src1[1]) * (1.0f - src2[1]));
-		if (temp < 0) temp = 0;
-		dst[1] = (temp * fac + src1[1] * mfac);
-
-		temp = 1.0f - ((1.0f - src1[2]) * (1.0f - src2[2]));
-		if (temp < 0) temp = 0;
-		dst[2] = (temp * fac + src1[2] * mfac);
+		while (i--) {
+			const float temp = max_ff(1.0f - ((1.0f - src1[i]) * (1.0f - src2[i])), 0.0f);
+			dst[i] = (temp * fac + src1[i] * mfac);
+		}
 	}
 	else {
 		/* no op */
@@ -1143,17 +909,20 @@ MINLINE void blend_color_softlight_float(float dst[3], const float src1[3], cons
 {
 	const float fac = src2[3];
 	if (fac != 0.0f && fac < 1.0f) {
-		float temp;
-		float mfac = 1.0f - fac;
-
-		temp = (((src1[0] < 0.5f) ? ((src2[0] + 0.5f) * (src1[0])) : (1.0f - ((1.0f - ((src2[0]) + 0.5f)) * (1.0f - src1[0])))));
-		dst[0] = (temp * fac + src1[0] * mfac);
-
-		temp = (((src1[1] < 0.5f) ? ((src2[1] + 0.5f) * (src1[1])) : (1.0f - ((1.0f - ((src2[1]) + 0.5f)) * (1.0f - src1[1])))));
-		dst[1] = (temp * fac + src1[1] * mfac);
-
-		temp = (((src1[2] < 0.5f) ? ((src2[2] + 0.5f) * (src1[2])) : (1.0f - ((1.0f - ((src2[2]) + 0.5f)) * (1.0f - src1[2])))));
-		dst[2] = (temp * fac + src1[2] * mfac);
+		const float mfac = 1.0f - fac;
+		int i = 3;
+
+		while (i--) {
+			float temp;
+
+			if (src1[i] < 0.5f) {
+				temp = (src2[i] + 0.5f) * src1[i];
+			}
+			else {
+				temp = 1.0f - ((1.0f - (src2[i] + 0.5f)) * (1.0f - src1[i]));
+			}
+			dst[i] = (temp * fac + src1[i] * mfac);
+		}
 	}
 	else {
 		/* no op */
@@ -1165,44 +934,20 @@ MINLINE void blend_color_pinlight_float(float dst[3], const float src1[3], const
 {
 	const float fac = src2[3];
 	if (fac != 0.0f && fac < 1.0f) {
-		float temp;
-		float mfac = 1.0f - fac;
-
-		if (src2[0] > 0.5f) {
-			temp = 2 * (src2[0] - 0.5f);
-			if (src1[0] > temp)
-				temp = src1[0];
-		}
-		else {
-			temp = 2 * src2[0];
-			if (src1[0] < temp)
-				temp = src1[0];
-		}
-
-		dst[0] = (temp * fac + src1[0] * mfac);
-
-
-		if (src2[1] > 0.5f) {
-			temp = 2 * (src2[1] - 0.5f);
-			if (src1[1] > temp) temp = src1[1];
-		}
-		else {
-			temp = 2 * src2[1];
-			if (src1[1] < temp) temp = src1[1];
-		}
-
-		dst[1] = (temp * fac + src1[1] * mfac);
-
-
-		if (src2[2] > 0.5f) {
-			temp = 2 * (src2[2] - 0.5f);
-			if (src1[2] > temp) temp = src1[2];
-		}
-		else {
-			temp = 2 * src2[2];
-			if (src1[2] < temp) temp = src1[2];
+		const float mfac = 1.0f - fac;
+		int i = 3;
+
+		while (i--) {
+			float temp;
+
+			if (src2[i] > 0.5f) {
+				temp = max_ff(2.0f * (src2[i] - 0.5f), src1[i]);
+			}
+			else {
+				temp = min_ff(2.0f * src2[i], src1[i]);
+			}
+			dst[i] = (temp * fac + src1[i] * mfac);
 		}
-		dst[2] = (temp * fac + src1[2] * mfac);
 	}
 	else {
 		/* no op */
@@ -1215,41 +960,20 @@ MINLINE void blend_color_linearlight_float(float dst[3], const float src1[3], co
 {
 	const float fac = src2[3];
 	if (fac != 0.0f && fac < 1.0f) {
-		float temp;
-		float mfac = 1.0f - fac;
-
-		if (src2[0] > 0.5f) {
-			temp = src1[0] + 2 * (src2[0] - 0.5f);
-			if (temp > 1.0f)
-				temp = 1.0f;
-		}
-		else {
-			temp = src1[0] + 2 * src2[0] - 1.0f;
-			if (temp < 0) temp = 0;
-		}
-		dst[0] = (temp * fac + src1[0] * mfac);
-
-		if (src2[1] > 0.5f) {
-			temp = src1[1] + 2 * (src2[1] - 0.5f);
-			if (temp > 1.0f)
-				temp = 1.0f;
-		}
-		else {
-			temp = src1[1] + 2 * src2[1] - 1.0f;
-			if (temp < 0) temp = 0;
-		}
-		dst[1] = (temp * fac + src1[1] * mfac);
-
-		if (src2[2] > 0.5f) {
-			temp = src1[2] + 2 * (src2[2] - 0.5f);
-			if (temp > 1.0f)
-				temp = 1.0f;
+		const float mfac = 1.0f - fac;
+		int i = 3;
+
+		while (i--) {
+			float temp;
+
+			if (src2[i] > 0.5f) {
+				temp = min_ff(src1[i] + 2.0f * (src2[i] - 0.5f), 1.0f);
+			}
+			else {
+				temp = max_ff(src1[i] + 2.0f * src2[i] - 1.0f, 0.0f);
+			}
+			dst[i] = (temp * fac + src1[i] * mfac);
 		}
-		else {
-			temp = src1[2] + 2 * src2[2] - 1.0f;
-			if (temp < 0) temp = 0;
-		}
-		dst[2] = (temp * fac + src1[2] * mfac);
 	}
 	else {
 		/* no op */
@@ -1262,53 +986,26 @@ MINLINE void blend_color_vividlight_float(float dst[3], const float src1[3], con
 {
 	const float fac = src2[3];
 	if (fac != 0.0f && fac < 1.0f) {
-		float temp;
-		float mfac = 1.0f - fac;
-
-		if (src2[0] == 1.0f)
-			temp = 1.0f;
-		else if (src2[0] == 0)
-			temp = 0;
-		else if (src2[0] > 0.5f) {
-			temp = ((src1[0]) * 1.0f) / (2 * (1.0f - src2[0]));
-			if (temp > 1.0f) temp = 1.0f;
-		}
-		else {
-			temp = 1.0f - ((1.0f - src1[0]) * 1.0f / (2 * src2[0]));
-			if (temp < 0) temp = 0;
-		}
-
-		dst[0] = (temp * fac + src1[0] * mfac);
-
-		if (src2[1] == 1.0f)
-			temp = 1.0f;
-		else if (src2[1] == 0)
-			temp = 0;
-		else if (src2[1] > 0.5f) {
-			temp = ((src1[1]) * 1.0f) / (2 * (1.0f - src2[1]));
-			if (temp > 1.0f) temp = 1.0f;
-		}
-		else {
-			temp = 1.0f - ((1.0f - src1[1]) * 1.0f / (2 * src2[1]));
-			if (temp < 0) temp = 0;
-		}
+		const float mfac = 1.0f - fac;
+		int i = 3;
 
-		dst[1] = (temp * fac + src1[1] * mfac);
+		while (i--) {
+			float temp;
 
-		if (src2[2] == 1.0f)
-			temp = 1.0f;
-		else if (src2[2] == 0)
-			temp = 0;
-		else if (src2[2] > 0.5f) {
-			temp = ((src1[2]) * 1.0f) / (2 * (1.0f - src2[2]));
-			if (temp > 1.0f) temp = 1.0f;
-		}
-		else {
-			temp = 1.0f - ((1.0f - src1[2]) * 1.0f / (2 * src2[2]));
-			if (temp < 0) temp = 0;
+			if (src2[i] == 1.0f) {
+				temp = 1.0f;
+			}
+			else if (src2[i] == 0.0f) {
+				temp = 0.0f;
+			}
+			else if (src2[i] > 0.5f) {
+				temp = min_ff(((src1[i]) * 1.0f) / (2.0f * (1.0f - src2[i])), 1.0f);
+			}
+			else {
+				temp = max_ff(1.0f - ((1.0f - src1[i]) * 1.0f / (2.0f * src2[i])), 0.0f);
+			}
+			dst[i] = (temp * fac + src1[i] * mfac);
 		}
-
-		dst[2] = (temp * fac + src1[2] * mfac);
 	}
 	else {
 		/* no op */
@@ -1320,20 +1017,12 @@ MINLINE void blend_color_difference_float(float dst[3], const float src1[3], con
 {
 	const float fac = src2[3];
 	if (fac != 0.0f && fac < 1.0f) {
-		float temp;
-		float mfac = 1.0f - fac;
-		temp = src1[0] - src2[0];
-		if (temp < 0) temp = -temp;
-		dst[0] = (temp * fac + src1[0] * mfac);
-
-		temp = src1[1] - src2[1];
-		if (temp < 0) temp = -temp;
-		dst[1] = (temp * fac + src1[1] * mfac);
-
-		temp = src1[2] - src2[2];
-		if (temp < 0) temp = -temp;
-		dst[2] = (temp * fac + src1[2] * mfac);
+		const float mfac = 1.0f - fac;
+		int i = 3;
 
+		while (i--) {
+			dst[i] = (fabsf(src1[i] - src2[i]) * fac + src1[i] * mfac);
+		}
 	}
 	else {
 		/* no op */
@@ -1346,16 +1035,13 @@ MINLINE void blend_color_exclusion_float(float dst[3], const float src1[3], cons
 {
 	const float fac = src2[3];
 	if (fac != 0.0f && fac < 1.0f) {
-		float temp;
-		float mfac = 1.0f - fac;
-		temp = 0.5f - ((2 * (src1[0] - 0.5f) * (src2[0] - 0.5f)));
-		dst[0] = (temp * fac + src1[0] * mfac);
-
-		temp = 0.5f - ((2 * (src1[1] - 0.5f) * (src2[1] - 0.5f)));
-		dst[1] = (temp * fac + src1[1] * mfac);
+		const float mfac = 1.0f - fac;
+		int i = 3;
 
-		temp = 0.5f - ((2 * (src1[2] - 0.5f) * (src2[2] - 0.5f)));
-		dst[2] = (temp * fac + src1[2] * mfac);
+		while (i--) {
+			const float temp = 0.5f - ((2 * (src1[i] - 0.5f) * (src2[i] - 0.5f)));
+			dst[i] = (temp * fac + src1[i] * mfac);
+		}
 	}
 	else {
 		/* no op */
@@ -1368,14 +1054,14 @@ MINLINE void blend_color_color_float(float dst[3], const float src1[3], const fl
 {
 	const float fac = src2[3];
 	if (fac != 0.0f && fac < 1.0f) {
-		float mfac = 1.0f - fac;
+		const float mfac = 1.0f - fac;
 		float h1, s1, v1;
 		float h2, s2, v2;
 		float r, g, b;
+
 		rgb_to_hsv(src1[0], src1[1], src1[2], &h1, &s1, &v1);
 		rgb_to_hsv(src2[0], src2[1], src2[2], &h2, &s2, &v2);
 
-
 		h1 = h2;
 		s1 = s2;
 
@@ -1396,14 +1082,14 @@ MINLINE void blend_color_hue_float(float dst[3], const float src1[3], const floa
 {
 	const float fac = src2[3];
 	if (fac != 0.0f && fac < 1.0f) {
-		float mfac = 1.0f - fac;
+		const float mfac = 1.0f - fac;
 		float h1, s1, v1;
 		float h2, s2, v2;
 		float r, g, b;
+
 		rgb_to_hsv(src1[0], src1[1], src1[2], &h1, &s1, &v1);
 		rgb_to_hsv(src2[0], src2[1], src2[2], &h2, &s2, &v2);
 
-
 		h1 = h2;
 
 		hsv_to_rgb(h1, s1, v1, &r, &g, &b);
@@ -1422,10 +1108,11 @@ MINLINE void blend_color_saturation_float(float dst[3], const float src1[3], con
 {
 	const float fac = src2[3];
 	if (fac != 0.0f && fac < 1.0f) {
-		float mfac = 1.0f - fac;
+		const float mfac = 1.0f - fac;
 		float h1, s1, v1;
 		float h2, s2, v2;
 		float r, g, b;
+
 		rgb_to_hsv(src1[0], src1[1], src1[2], &h1, &s1, &v1);
 		rgb_to_hsv(src2[0], src2[1], src2[2], &h2, &s2, &v2);
 
@@ -1448,14 +1135,14 @@ MINLINE void blend_color_luminosity_float(float dst[3], const float src1[3], con
 {
 	const float fac = src2[3];
 	if (fac != 0.0f && fac < 1.0f) {
-		float mfac = 1.0f - fac;
+		const float mfac = 1.0f - fac;
 		float h1, s1, v1;
 		float h2, s2, v2;
 		float r, g, b;
+
 		rgb_to_hsv(src1[0], src1[1], src1[2], &h1, &s1, &v1);
 		rgb_to_hsv(src2[0], src2[1], src2[2], &h2, &s2, &v2);
 
-
 		v1 = v2;
 		hsv_to_rgb(h1, s1, v1, &r, &g, &b);
 
@@ -1473,7 +1160,7 @@ MINLINE void blend_color_luminosity_float(float dst[3], const float src1[3], con
 MINLINE void blend_color_interpolate_float(float dst[4], const float src1[4], const float src2[4], float t)
 {
 	/* interpolation, colors are premultiplied so it goes fine */
-	float mt = 1.0f - t;
+	const float mt = 1.0f - t;
 
 	dst[0] = mt * src1[0] + t * src2[0];
 	dst[1] = mt * src1[1] + t * src2[1];