Fix paint float color blending bugs with alpha 1.0 and vivid light.

For some blend modes there would be no effect with factor 1.0, even if factor
0.999 would give a very different image. Now the result should have no
discontinuity.

Differential Revision: https://developer.blender.org/D2925

1 files changed, 20 insertions, 20 deletions

diff --git a/source/blender/blenlib/intern/math_color_blend_inline.c b/source/blender/blenlib/intern/math_color_blend_inline.c
index dc3874f83a2..1af2a0cd6a2 100644
--- a/source/blender/blenlib/intern/math_color_blend_inline.c
+++ b/source/blender/blenlib/intern/math_color_blend_inline.c
@@ -439,10 +439,10 @@ MINLINE void blend_color_vividlight_byte(unsigned char dst[4], unsigned const ch
 			int temp;
 
 			if (src2[i] == 255) {
-				temp = 255;
+				temp = (src1[i] == 0) ? 127 : 255;
 			}
 			else if (src2[i] == 0) {
-				temp = 0;
+				temp = (src1[i] == 255) ? 127 : 0;
 			}
 			else if (src2[i] > 127) {
 				temp = min_ii(((src1[i]) * 255) / (2 * (255 - src2[i])), 255);
@@ -784,7 +784,7 @@ MINLINE void blend_color_add_alpha_float(float dst[4], const float src1[4], cons
 MINLINE void blend_color_overlay_float(float dst[4], const float src1[4], const float src2[4])
 {
 	const float fac = src2[3];
-	if (fac != 0.0f && fac < 1.0f) {
+	if (fac != 0.0f) {
 		const float mfac = 1.0f - fac;
 		int i = 3;
 
@@ -810,7 +810,7 @@ MINLINE void blend_color_overlay_float(float dst[4], const float src1[4], const
 MINLINE void blend_color_hardlight_float(float dst[4], const float src1[4], const float src2[4])
 {
 	const float fac = src2[3];
-	if (fac != 0.0f && fac < 1.0f) {
+	if (fac != 0.0f) {
 		const float mfac = 1.0f - fac;
 		int i = 3;
 
@@ -835,7 +835,7 @@ MINLINE void blend_color_hardlight_float(float dst[4], const float src1[4], cons
 MINLINE void blend_color_burn_float(float dst[4], const float src1[4], const float src2[4])
 {
 	const float fac = src2[3];
-	if (fac != 0.0f && fac < 1.0f) {
+	if (fac != 0.0f) {
 		const float mfac = 1.0f - fac;
 		int i = 3;
 
@@ -853,7 +853,7 @@ MINLINE void blend_color_burn_float(float dst[4], const float src1[4], const flo
 MINLINE void blend_color_linearburn_float(float dst[4], const float src1[4], const float src2[4])
 {
 	const float fac = src2[3];
-	if (fac != 0.0f && fac < 1.0f) {
+	if (fac != 0.0f) {
 		const float mfac = 1.0f - fac;
 		int i = 3;
 
@@ -872,7 +872,7 @@ MINLINE void blend_color_linearburn_float(float dst[4], const float src1[4], con
 MINLINE void blend_color_dodge_float(float dst[4], const float src1[4], const float src2[4])
 {
 	const float fac = src2[3];
-	if (fac != 0.0f && fac < 1.0f) {
+	if (fac != 0.0f) {
 		const float mfac = 1.0f - fac;
 		int i = 3;
 
@@ -890,7 +890,7 @@ MINLINE void blend_color_dodge_float(float dst[4], const float src1[4], const fl
 MINLINE void blend_color_screen_float(float dst[4], const float src1[4], const float src2[4])
 {
 	const float fac = src2[3];
-	if (fac != 0.0f && fac < 1.0f) {
+	if (fac != 0.0f) {
 		const float mfac = 1.0f - fac;
 		int i = 3;
 
@@ -908,7 +908,7 @@ MINLINE void blend_color_screen_float(float dst[4], const float src1[4], const f
 MINLINE void blend_color_softlight_float(float dst[4], const float src1[4], const float src2[4])
 {
 	const float fac = src2[3];
-	if (fac != 0.0f && fac < 1.0f) {
+	if (fac != 0.0f) {
 		const float mfac = 1.0f - fac;
 		int i = 3;
 
@@ -933,7 +933,7 @@ MINLINE void blend_color_softlight_float(float dst[4], const float src1[4], cons
 MINLINE void blend_color_pinlight_float(float dst[4], const float src1[4], const float src2[4])
 {
 	const float fac = src2[3];
-	if (fac != 0.0f && fac < 1.0f) {
+	if (fac != 0.0f) {
 		const float mfac = 1.0f - fac;
 		int i = 3;
 
@@ -959,7 +959,7 @@ MINLINE void blend_color_pinlight_float(float dst[4], const float src1[4], const
 MINLINE void blend_color_linearlight_float(float dst[4], const float src1[4], const float src2[4])
 {
 	const float fac = src2[3];
-	if (fac != 0.0f && fac < 1.0f) {
+	if (fac != 0.0f) {
 		const float mfac = 1.0f - fac;
 		int i = 3;
 
@@ -985,7 +985,7 @@ MINLINE void blend_color_linearlight_float(float dst[4], const float src1[4], co
 MINLINE void blend_color_vividlight_float(float dst[4], const float src1[4], const float src2[4])
 {
 	const float fac = src2[3];
-	if (fac != 0.0f && fac < 1.0f) {
+	if (fac != 0.0f) {
 		const float mfac = 1.0f - fac;
 		int i = 3;
 
@@ -993,10 +993,10 @@ MINLINE void blend_color_vividlight_float(float dst[4], const float src1[4], con
 			float temp;
 
 			if (src2[i] == 1.0f) {
-				temp = 1.0f;
+				temp = (src1[i] == 0.0f) ? 0.5f : 1.0f;
 			}
 			else if (src2[i] == 0.0f) {
-				temp = 0.0f;
+				temp = (src1[i] == 1.0f) ? 0.5f : 0.0f;
 			}
 			else if (src2[i] > 0.5f) {
 				temp = min_ff(((src1[i]) * 1.0f) / (2.0f * (1.0f - src2[i])), 1.0f);
@@ -1016,7 +1016,7 @@ MINLINE void blend_color_vividlight_float(float dst[4], const float src1[4], con
 MINLINE void blend_color_difference_float(float dst[4], const float src1[4], const float src2[4])
 {
 	const float fac = src2[3];
-	if (fac != 0.0f && fac < 1.0f) {
+	if (fac != 0.0f) {
 		const float mfac = 1.0f - fac;
 		int i = 3;
 
@@ -1034,7 +1034,7 @@ MINLINE void blend_color_difference_float(float dst[4], const float src1[4], con
 MINLINE void blend_color_exclusion_float(float dst[4], const float src1[4], const float src2[4])
 {
 	const float fac = src2[3];
-	if (fac != 0.0f && fac < 1.0f) {
+	if (fac != 0.0f) {
 		const float mfac = 1.0f - fac;
 		int i = 3;
 
@@ -1053,7 +1053,7 @@ MINLINE void blend_color_exclusion_float(float dst[4], const float src1[4], cons
 MINLINE void blend_color_color_float(float dst[4], const float src1[4], const float src2[4])
 {
 	const float fac = src2[3];
-	if (fac != 0.0f && fac < 1.0f) {
+	if (fac != 0.0f) {
 		const float mfac = 1.0f - fac;
 		float h1, s1, v1;
 		float h2, s2, v2;
@@ -1081,7 +1081,7 @@ MINLINE void blend_color_color_float(float dst[4], const float src1[4], const fl
 MINLINE void blend_color_hue_float(float dst[4], const float src1[4], const float src2[4])
 {
 	const float fac = src2[3];
-	if (fac != 0.0f && fac < 1.0f) {
+	if (fac != 0.0f) {
 		const float mfac = 1.0f - fac;
 		float h1, s1, v1;
 		float h2, s2, v2;
@@ -1107,7 +1107,7 @@ MINLINE void blend_color_hue_float(float dst[4], const float src1[4], const floa
 MINLINE void blend_color_saturation_float(float dst[4], const float src1[4], const float src2[4])
 {
 	const float fac = src2[3];
-	if (fac != 0.0f && fac < 1.0f) {
+	if (fac != 0.0f) {
 		const float mfac = 1.0f - fac;
 		float h1, s1, v1;
 		float h2, s2, v2;
@@ -1134,7 +1134,7 @@ MINLINE void blend_color_saturation_float(float dst[4], const float src1[4], con
 MINLINE void blend_color_luminosity_float(float dst[4], const float src1[4], const float src2[4])
 {
 	const float fac = src2[3];
-	if (fac != 0.0f && fac < 1.0f) {
+	if (fac != 0.0f) {
 		const float mfac = 1.0f - fac;
 		float h1, s1, v1;
 		float h2, s2, v2;