reformatted and restructured tonemap.glsl

1 files changed, 218 insertions, 231 deletions

diff --git a/drivers/gles3/shaders/tonemap.glsl b/drivers/gles3/shaders/tonemap.glsl
index ceb37d703a..63475c9039 100644
--- a/drivers/gles3/shaders/tonemap.glsl
+++ b/drivers/gles3/shaders/tonemap.glsl
@@ -1,28 +1,27 @@
 [vertex]
 
-
-layout(location=0) in highp vec4 vertex_attrib;
-layout(location=4) in vec2 uv_in;
+layout (location = 0) in highp vec4 vertex_attrib;
+layout (location = 4) in vec2 uv_in;
 
 out vec2 uv_interp;
 
-void main() {
-
+void main()
+{
 	gl_Position = vertex_attrib;
+
 	uv_interp = uv_in;
-#ifdef V_FLIP
-	uv_interp.y = 1.0-uv_interp.y;
-#endif
 
+	#ifdef V_FLIP
+		uv_interp.y = 1.0f - uv_interp.y;
+	#endif
 }
 
 [fragment]
 
 #if !defined(GLES_OVER_GL)
-precision mediump float;
+	precision mediump float;
 #endif
 
-
 in vec2 uv_interp;
 
 uniform highp sampler2D source; //texunit:0
@@ -31,298 +30,286 @@ uniform float exposure;
 uniform float white;
 
 #ifdef USE_AUTO_EXPOSURE
-
-uniform highp sampler2D source_auto_exposure; //texunit:1
-uniform highp float auto_exposure_grey;
-
+	uniform highp sampler2D source_auto_exposure; //texunit:1
+	uniform highp float auto_exposure_grey;
 #endif
 
 #if defined(USE_GLOW_LEVEL1) || defined(USE_GLOW_LEVEL2) || defined(USE_GLOW_LEVEL3) || defined(USE_GLOW_LEVEL4) || defined(USE_GLOW_LEVEL5) || defined(USE_GLOW_LEVEL6) || defined(USE_GLOW_LEVEL7)
+	#define USING_GLOW // only use glow when at least one glow level is selected
 
-uniform highp sampler2D source_glow; //texunit:2
-uniform highp float glow_intensity;
-
+	uniform highp sampler2D source_glow; //texunit:2
+	uniform highp float glow_intensity;
 #endif
 
 #ifdef USE_BCS
-
-uniform vec3 bcs;
-
+	uniform vec3 bcs;
 #endif
 
 #ifdef USE_COLOR_CORRECTION
-
-uniform sampler2D color_correction; //texunit:3
-
+	uniform sampler2D color_correction; //texunit:3
 #endif
 
-
-layout(location = 0) out vec4 frag_color;
+layout (location = 0) out vec4 frag_color;
 
 #ifdef USE_GLOW_FILTER_BICUBIC
+	// w0, w1, w2, and w3 are the four cubic B-spline basis functions
+	float w0(float a)
+	{
+		return (1.0f / 6.0f) * (a * (a * (-a + 3.0f) - 3.0f) + 1.0f);
+	}
 
-// w0, w1, w2, and w3 are the four cubic B-spline basis functions
-float w0(float a)
-{
-    return (1.0/6.0)*(a*(a*(-a + 3.0) - 3.0) + 1.0);
-}
-
-float w1(float a)
-{
-    return (1.0/6.0)*(a*a*(3.0*a - 6.0) + 4.0);
-}
-
-float w2(float a)
-{
-    return (1.0/6.0)*(a*(a*(-3.0*a + 3.0) + 3.0) + 1.0);
-}
-
-float w3(float a)
-{
-    return (1.0/6.0)*(a*a*a);
-}
-
-// g0 and g1 are the two amplitude functions
-float g0(float a)
-{
-    return w0(a) + w1(a);
-}
+	float w1(float a)
+	{
+		return (1.0f / 6.0f) * (a * a * (3.0f * a - 6.0f) + 4.0f);
+	}
 
-float g1(float a)
-{
-    return w2(a) + w3(a);
-}
+	float w2(float a)
+	{
+		return (1.0f / 6.0f) * (a * (a * (-3.0f * a + 3.0f) + 3.0f) + 1.0f);
+	}
 
-// h0 and h1 are the two offset functions
-float h0(float a)
-{
-    return -1.0 + w1(a) / (w0(a) + w1(a));
-}
+	float w3(float a)
+	{
+		return (1.0f / 6.0f) * (a * a * a);
+	}
 
-float h1(float a)
-{
-    return 1.0 + w3(a) / (w2(a) + w3(a));
-}
+	// g0 and g1 are the two amplitude functions
+	float g0(float a)
+	{
+		return w0(a) + w1(a);
+	}
 
-uniform ivec2 glow_texture_size;
+	float g1(float a)
+	{
+		return w2(a) + w3(a);
+	}
 
-vec4 texture2D_bicubic(sampler2D tex, vec2 uv,int p_lod)
-{
-	float lod=float(p_lod);
-	vec2 tex_size = vec2(glow_texture_size >> p_lod);
-	vec2 pixel_size =1.0/tex_size;
-	uv = uv*tex_size + 0.5;
-	vec2 iuv = floor( uv );
-	vec2 fuv = fract( uv );
-
-	float g0x = g0(fuv.x);
-	float g1x = g1(fuv.x);
-	float h0x = h0(fuv.x);
-	float h1x = h1(fuv.x);
-	float h0y = h0(fuv.y);
-	float h1y = h1(fuv.y);
-
-	vec2 p0 = (vec2(iuv.x + h0x, iuv.y + h0y) - 0.5) * pixel_size;
-	vec2 p1 = (vec2(iuv.x + h1x, iuv.y + h0y) - 0.5) * pixel_size;
-	vec2 p2 = (vec2(iuv.x + h0x, iuv.y + h1y) - 0.5) * pixel_size;
-	vec2 p3 = (vec2(iuv.x + h1x, iuv.y + h1y) - 0.5) * pixel_size;
-
-	return g0(fuv.y) * (g0x * textureLod(tex, p0,lod)  +
-			    g1x * textureLod(tex, p1,lod)) +
-			g1(fuv.y) * (g0x * textureLod(tex, p2,lod)  +
-				     g1x * textureLod(tex, p3,lod));
-}
+	// h0 and h1 are the two offset functions
+	float h0(float a)
+	{
+		return -1.0f + w1(a) / (w0(a) + w1(a));
+	}
 
+	float h1(float a)
+	{
+		return 1.0f + w3(a) / (w2(a) + w3(a));
+	}
 
+	uniform ivec2 glow_texture_size;
 
-#define GLOW_TEXTURE_SAMPLE(m_tex,m_uv,m_lod) texture2D_bicubic(m_tex,m_uv,m_lod)
+	vec4 texture2D_bicubic(sampler2D tex, vec2 uv, int p_lod)
+	{
+		float lod = float(p_lod);
+		vec2 tex_size = vec2(glow_texture_size >> p_lod);
+		vec2 pixel_size = vec2(1.0f) / tex_size;
+
+		uv = uv * tex_size + vec2(0.5f);
+
+		vec2 iuv = floor(uv);
+		vec2 fuv = fract(uv);
+
+		float g0x = g0(fuv.x);
+		float g1x = g1(fuv.x);
+		float h0x = h0(fuv.x);
+		float h1x = h1(fuv.x);
+		float h0y = h0(fuv.y);
+		float h1y = h1(fuv.y);
+
+		vec2 p0 = (vec2(iuv.x + h0x, iuv.y + h0y) - vec2(0.5f)) * pixel_size;
+		vec2 p1 = (vec2(iuv.x + h1x, iuv.y + h0y) - vec2(0.5f)) * pixel_size;
+		vec2 p2 = (vec2(iuv.x + h0x, iuv.y + h1y) - vec2(0.5f)) * pixel_size;
+		vec2 p3 = (vec2(iuv.x + h1x, iuv.y + h1y) - vec2(0.5f)) * pixel_size;
+
+		return g0(fuv.y) * (g0x * textureLod(tex, p0,lod) +
+			g1x * textureLod(tex, p1,lod)) +
+			g1(fuv.y) * (g0x * textureLod(tex, p2,lod) +
+			g1x * textureLod(tex, p3,lod));
+	}
 
+	#define GLOW_TEXTURE_SAMPLE(m_tex, m_uv, m_lod) texture2D_bicubic(m_tex, m_uv, m_lod)
 #else
-
-#define GLOW_TEXTURE_SAMPLE(m_tex,m_uv,m_lod) textureLod(m_tex,m_uv,float(m_lod))
-
+	#define GLOW_TEXTURE_SAMPLE(m_tex, m_uv, m_lod) textureLod(m_tex, m_uv, float(m_lod))
 #endif
 
+vec3 tonemap_filmic(vec3 color, float white)
+{
+	const float A = 0.15f;
+	const float B = 0.50f;
+	const float C = 0.10f;
+	const float D = 0.20f;
+	const float E = 0.02f;
+	const float F = 0.30f;
+	const float W = 11.2f;
+
+	vec3 color_tonemapped = ((color * (A * color + C * B) + D * E) / (color * (A * color + B) + D * F)) - E / F;
+	float white_tonemapped = ((white * (A * white + C * B) + D * E) / (white * (A * white + B) + D * F)) - E / F;
+
+	return clamp(color_tonemapped / white_tonemapped, vec3(0.0f), vec3(1.0f));
+}
 
-vec3 tonemap_filmic(vec3 color,float white) {
-
-	float A = 0.15;
-	float B = 0.50;
-	float C = 0.10;
-	float D = 0.20;
-	float E = 0.02;
-	float F = 0.30;
-	float W = 11.2;
-
-	vec3 coltn = ((color*(A*color+C*B)+D*E)/(color*(A*color+B)+D*F))-E/F;
-	float whitetn = ((white*(A*white+C*B)+D*E)/(white*(A*white+B)+D*F))-E/F;
+vec3 tonemap_aces(vec3 color, float white)
+{
+	const float A = 2.51f;
+	const float B = 0.03f;
+	const float C = 2.43f;
+	const float D = 0.59f;
+	const float E = 0.14f;
 
-	return coltn/whitetn;
+	vec3 color_tonemapped = (color * (A * color + B)) / (color * (C * color + D) + E);
+	float white_tonemapped = (white * (A * white + B)) / (white * (C * white + D) + E);
 
+	return clamp(color_tonemapped / white_tonemapped, vec3(0.0f), vec3(1.0f));
 }
 
-vec3 tonemap_aces(vec3 color, float white) {
-	float a = 2.51f;
-	float b = 0.03f;
-	float c = 2.43f;
-	float d = 0.59f;
-	float e = 0.14f;
-	color = (color * (a * color + b)) / (color * (c * color + d) + e);
-	return clamp(color / vec3((white * (a * white + b)) / (white * (c * white + d) + e)), vec3(0.0), vec3(1.0));
+vec3 tonemap_reindhart(vec3 color, float white)
+{
+	return clamp((color) / (1.0f + color) * (1.0f + (color / (white))), vec3(0.0f), vec3(1.0f)); // whitepoint is probably not in linear space here!
 }
 
-vec3 tonemap_reindhart(vec3 color,float white) {
-
-	return ( color * ( 1.0 + ( color / ( white) ) ) ) / ( 1.0 + color );
+vec3 linear_to_srgb(vec3 color) // convert linear rgb to srgb, assumes clamped input in range [0;1]
+{
+	const vec3 a = vec3(0.055f);
+	return mix((vec3(1.0f) + a) * pow(color.rgb, vec3(1.0f / 2.4f)) - a, 12.92f * color.rgb, lessThan(color.rgb, vec3(0.0031308f)));
 }
 
-void main() {
-
-	vec4 color = textureLod(source, uv_interp, 0.0);
-
-#ifdef USE_AUTO_EXPOSURE
-
-	color/=texelFetch(source_auto_exposure,ivec2(0,0),0).r/auto_exposure_grey;
-#endif
-
-	color*=exposure;
-
-#if defined(USE_GLOW_LEVEL1) || defined(USE_GLOW_LEVEL2) || defined(USE_GLOW_LEVEL3) || defined(USE_GLOW_LEVEL4) || defined(USE_GLOW_LEVEL5) || defined(USE_GLOW_LEVEL6) || defined(USE_GLOW_LEVEL7)
-#define USING_GLOW
-#endif
-
-#if defined(USING_GLOW)
-	vec3 glow = vec3(0.0);
-
-#ifdef USE_GLOW_LEVEL1
-
-	glow+=GLOW_TEXTURE_SAMPLE(source_glow,uv_interp,1).rgb;
-#endif
-
-#ifdef USE_GLOW_LEVEL2
-	glow+=GLOW_TEXTURE_SAMPLE(source_glow,uv_interp,2).rgb;
-#endif
-
-#ifdef USE_GLOW_LEVEL3
-	glow+=GLOW_TEXTURE_SAMPLE(source_glow,uv_interp,3).rgb;
-#endif
-
-#ifdef USE_GLOW_LEVEL4
-	glow+=GLOW_TEXTURE_SAMPLE(source_glow,uv_interp,4).rgb;
-#endif
-
-#ifdef USE_GLOW_LEVEL5
-	glow+=GLOW_TEXTURE_SAMPLE(source_glow,uv_interp,5).rgb;
-#endif
-
-#ifdef USE_GLOW_LEVEL6
-	glow+=GLOW_TEXTURE_SAMPLE(source_glow,uv_interp,6).rgb;
-#endif
-
-#ifdef USE_GLOW_LEVEL7
-	glow+=GLOW_TEXTURE_SAMPLE(source_glow,uv_interp,7).rgb;
-#endif
-
-
-	glow *= glow_intensity;
+vec3 apply_tonemapping(vec3 color, float white) // inputs are LINEAR, always outputs clamped [0;1] color
+{
+	#ifdef USE_REINDHART_TONEMAPPER
+		return tonemap_reindhart(color, white);
+	#endif
 
-#endif
+	#ifdef USE_FILMIC_TONEMAPPER
+		return tonemap_filmic(color, white);
+	#endif
 
+	#ifdef USE_ACES_TONEMAPPER
+		return tonemap_aces(color, white);
+	#endif
 
-#ifdef USE_REINDHART_TONEMAPPER
+	return clamp(color, vec3(0.0f), vec3(1.0f)); // no other seleced -> linear
+}
 
-	color.rgb = tonemap_reindhart(color.rgb,white);
+vec3 gather_glow(sampler2D tex, vec2 uv) // sample all selected glow levels
+{
+	vec3 glow = vec3(0.0f);
 
-# if defined(USING_GLOW)
-	glow = tonemap_reindhart(glow,white);
-# endif
+	#ifdef USE_GLOW_LEVEL1
+		glow += GLOW_TEXTURE_SAMPLE(tex, uv, 1).rgb;
+	#endif
 
-#endif
+	#ifdef USE_GLOW_LEVEL2
+		glow += GLOW_TEXTURE_SAMPLE(tex, uv, 2).rgb;
+	#endif
 
-#ifdef USE_FILMIC_TONEMAPPER
+	#ifdef USE_GLOW_LEVEL3
+		glow += GLOW_TEXTURE_SAMPLE(tex, uv, 3).rgb;
+	#endif
 
-	color.rgb = tonemap_filmic(color.rgb,white);
+	#ifdef USE_GLOW_LEVEL4
+		glow += GLOW_TEXTURE_SAMPLE(tex, uv, 4).rgb;
+	#endif
 
-# if defined(USING_GLOW)
-	glow = tonemap_filmic(glow,white);
-# endif
+	#ifdef USE_GLOW_LEVEL5
+		glow += GLOW_TEXTURE_SAMPLE(tex, uv, 5).rgb;
+	#endif
 
-#endif
+	#ifdef USE_GLOW_LEVEL6
+		glow += GLOW_TEXTURE_SAMPLE(tex, uv, 6).rgb;
+	#endif
 
-#ifdef USE_ACES_TONEMAPPER
+	#ifdef USE_GLOW_LEVEL7
+		glow += GLOW_TEXTURE_SAMPLE(tex, uv, 7).rgb;
+	#endif
 
-	color.rgb = tonemap_aces(color.rgb,white);
+	return glow;
+}
 
-# if defined(USING_GLOW)
-	glow = tonemap_aces(glow,white);
-# endif
+vec3 apply_glow(vec3 color, vec3 glow) // apply glow using the selected blending mode
+{
+	#ifdef USE_GLOW_REPLACE
+		color = glow;
+	#endif
 
-#endif
+	#ifdef USE_GLOW_SCREEN
+		color = max((color + glow) - (color * glow), vec3(0.0));
+	#endif
 
-#ifdef KEEP_3D_LINEAR
-	// leave color as is...
-#else
-	//regular Linear -> SRGB conversion
-	vec3 a = vec3(0.055);
-	color.rgb = mix( (vec3(1.0)+a)*pow(color.rgb,vec3(1.0/2.4))-a , 12.92*color.rgb , lessThan(color.rgb,vec3(0.0031308)));
-#endif
+	#ifdef USE_GLOW_SOFTLIGHT
+		glow = glow * vec3(0.5f) + vec3(0.5f);
 
-#if defined(USING_GLOW)
-	glow = mix( (vec3(1.0)+a)*pow(glow,vec3(1.0/2.4))-a , 12.92*glow , lessThan(glow,vec3(0.0031308)));
-#endif
+		color.r = (glow.r <= 0.5f) ? (color.r - (1.0f - 2.0f * glow.r) * color.r * (1.0f - color.r)) : (((glow.r > 0.5f) && (color.r <= 0.25f)) ? (color.r + (2.0f * glow.r - 1.0f) * (4.0f * color.r * (4.0f * color.r + 1.0f) * (color.r - 1.0f) + 7.0f * color.r)) : (color.r + (2.0f * glow.r - 1.0f) * (sqrt(color.r) - color.r)));
+		color.g = (glow.g <= 0.5f) ? (color.g - (1.0f - 2.0f * glow.g) * color.g * (1.0f - color.g)) : (((glow.g > 0.5f) && (color.g <= 0.25f)) ? (color.g + (2.0f * glow.g - 1.0f) * (4.0f * color.g * (4.0f * color.g + 1.0f) * (color.g - 1.0f) + 7.0f * color.g)) : (color.g + (2.0f * glow.g - 1.0f) * (sqrt(color.g) - color.g)));
+		color.b = (glow.b <= 0.5f) ? (color.b - (1.0f - 2.0f * glow.b) * color.b * (1.0f - color.b)) : (((glow.b > 0.5f) && (color.b <= 0.25f)) ? (color.b + (2.0f * glow.b - 1.0f) * (4.0f * color.b * (4.0f * color.b + 1.0f) * (color.b - 1.0f) + 7.0f * color.b)) : (color.b + (2.0f * glow.b - 1.0f) * (sqrt(color.b) - color.b)));
+	#endif
 
-//glow needs to be added in SRGB space (together with image space effects)
+	#if !defined(USE_GLOW_SCREEN) && !defined(USE_GLOW_SOFTLIGHT) && !defined(USE_GLOW_REPLACE) // no other selected -> additive
+		color += glow;
+	#endif
 
-	color.rgb = clamp(color.rgb,0.0,1.0);
+	return color;
+}
 
-#if defined(USING_GLOW)
-	glow = clamp(glow,0.0,1.0);
-#endif
+vec3 apply_bcs(vec3 color, vec3 bcs)
+{
+	color = mix(vec3(0.0f), color, bcs.x);
+	color = mix(vec3(0.5f), color, bcs.y);
+	color = mix(vec3(dot(vec3(1.0f), color) * 0.33333f), color, bcs.z);
 
-#ifdef USE_GLOW_REPLACE
+	return color;
+}
 
-	color.rgb = glow;
+vec3 apply_color_correction(vec3 color, sampler2D correction_tex)
+{
+	color.r = texture(correction_tex, vec2(color.r, 0.0f)).r;
+	color.g = texture(correction_tex, vec2(color.g, 0.0f)).g;
+	color.b = texture(correction_tex, vec2(color.b, 0.0f)).b;
 
-#endif
+	return color;
+}
 
-#ifdef USE_GLOW_SCREEN
+void main()
+{
+	vec3 color = textureLod(source, uv_interp, 0.0f).rgb;
 
-	color.rgb = max((color.rgb + glow) - (color.rgb * glow), vec3(0.0));
+	// Exposure
 
-#endif
+	#ifdef USE_AUTO_EXPOSURE
+		color /= texelFetch(source_auto_exposure, ivec2(0, 0), 0).r / auto_exposure_grey;
+	#endif
 
-#ifdef USE_GLOW_SOFTLIGHT
+	color *= exposure;
 
-	{
+	// Early Tonemap & SRGB Conversion
 
-		glow = (glow * 0.5) + 0.5;
-		color.r =  (glow.r <= 0.5) ? (color.r - (1.0 - 2.0 * glow.r) * color.r * (1.0 - color.r)) : (((glow.r > 0.5) && (color.r <= 0.25)) ? (color.r + (2.0 * glow.r - 1.0) * (4.0 * color.r * (4.0 * color.r + 1.0) * (color.r - 1.0) + 7.0 * color.r)) : (color.r + (2.0 * glow.r - 1.0) * (sqrt(color.r) - color.r)));
-		color.g =  (glow.g <= 0.5) ? (color.g - (1.0 - 2.0 * glow.g) * color.g * (1.0 - color.g)) : (((glow.g > 0.5) && (color.g <= 0.25)) ? (color.g + (2.0 * glow.g - 1.0) * (4.0 * color.g * (4.0 * color.g + 1.0) * (color.g - 1.0) + 7.0 * color.g)) : (color.g + (2.0 * glow.g - 1.0) * (sqrt(color.g) - color.g)));
-		color.b =  (glow.b <= 0.5) ? (color.b - (1.0 - 2.0 * glow.b) * color.b * (1.0 - color.b)) : (((glow.b > 0.5) && (color.b <= 0.25)) ? (color.b + (2.0 * glow.b - 1.0) * (4.0 * color.b * (4.0 * color.b + 1.0) * (color.b - 1.0) + 7.0 * color.b)) : (color.b + (2.0 * glow.b - 1.0) * (sqrt(color.b) - color.b)));
-	}
+	color = apply_tonemapping(color, white);
 
-#endif
+	#ifdef KEEP_3D_LINEAR
+		// leave color as is (-> don't convert to SRGB)
+	#else
+		color = linear_to_srgb(color); // regular linear -> SRGB conversion
+	#endif
 
-#if defined(USING_GLOW) && !defined(USE_GLOW_SCREEN) && !defined(USE_GLOW_SOFTLIGHT) && !defined(USE_GLOW_REPLACE)
-	//additive
-	color.rgb+=glow;
-#endif
+	// Glow
 
-#ifdef USE_BCS
+	#ifdef USING_GLOW
+		vec3 glow = gather_glow(source_glow, uv_interp) * glow_intensity;
 
-	color.rgb = mix(vec3(0.0),color.rgb,bcs.x);
-	color.rgb = mix(vec3(0.5),color.rgb,bcs.y);
-	color.rgb = mix(vec3(dot(vec3(1.0),color.rgb)*0.33333),color.rgb,bcs.z);
+		// high dynamic range -> SRGB
+		glow = apply_tonemapping(glow, white);
+		glow = linear_to_srgb(glow);
 
-#endif
+		color = apply_glow(color, glow);
+	#endif
 
-#ifdef USE_COLOR_CORRECTION
+	// Additional effects
 
-	color.r = texture(color_correction,vec2(color.r,0.0)).r;
-	color.g = texture(color_correction,vec2(color.g,0.0)).g;
-	color.b = texture(color_correction,vec2(color.b,0.0)).b;
-#endif
+	#ifdef USE_BCS
+		color = apply_bcs(color, bcs);
+	#endif
 
+	#ifdef USE_COLOR_CORRECTION
+		color = apply_color_correction(color, color_correction);
+	#endif
 
-	frag_color=vec4(color.rgb,1.0);
+	frag_color = vec4(color, 1.0f);
 }