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-rw-r--r--drivers/gles3/shaders/tonemap.glsl44
1 files changed, 28 insertions, 16 deletions
diff --git a/drivers/gles3/shaders/tonemap.glsl b/drivers/gles3/shaders/tonemap.glsl
index dd6d78849b..f1fe1742eb 100644
--- a/drivers/gles3/shaders/tonemap.glsl
+++ b/drivers/gles3/shaders/tonemap.glsl
@@ -124,13 +124,16 @@ vec4 texture2D_bicubic(sampler2D tex, vec2 uv, int p_lod) {
#endif
vec3 tonemap_filmic(vec3 color, float white) {
- const float A = 0.15f;
- const float B = 0.50f;
+ // exposure bias: input scale (color *= bias, white *= bias) to make the brightness consistent with other tonemappers
+ // also useful to scale the input to the range that the tonemapper is designed for (some require very high input values)
+ // has no effect on the curve's general shape or visual properties
+ const float exposure_bias = 2.0f;
+ const float A = 0.22f * exposure_bias * exposure_bias; // bias baked into constants for performance
+ const float B = 0.30f * exposure_bias;
const float C = 0.10f;
const float D = 0.20f;
- const float E = 0.02f;
+ const float E = 0.01f;
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;
@@ -139,10 +142,11 @@ vec3 tonemap_filmic(vec3 color, float white) {
}
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 exposure_bias = 0.85f;
+ const float A = 2.51f * exposure_bias * exposure_bias;
+ const float B = 0.03f * exposure_bias;
+ const float C = 2.43f * exposure_bias * exposure_bias;
+ const float D = 0.59f * exposure_bias;
const float E = 0.14f;
vec3 color_tonemapped = (color * (A * color + B)) / (color * (C * color + D) + E);
@@ -151,8 +155,8 @@ vec3 tonemap_aces(vec3 color, float white) {
return clamp(color_tonemapped / white_tonemapped, vec3(0.0f), vec3(1.0f));
}
-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_reinhard(vec3 color, float white) {
+ return clamp((white * color + color) / (color * white + white), vec3(0.0f), vec3(1.0f));
}
vec3 linear_to_srgb(vec3 color) { // convert linear rgb to srgb, assumes clamped input in range [0;1]
@@ -160,9 +164,10 @@ vec3 linear_to_srgb(vec3 color) { // convert linear rgb to srgb, assumes clamped
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)));
}
-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);
+// inputs are LINEAR, If Linear tonemapping is selected no transform is performed else outputs are clamped [0, 1] color
+vec3 apply_tonemapping(vec3 color, float white) {
+#ifdef USE_REINHARD_TONEMAPPER
+ return tonemap_reinhard(color, white);
#endif
#ifdef USE_FILMIC_TONEMAPPER
@@ -173,7 +178,7 @@ vec3 apply_tonemapping(vec3 color, float white) { // inputs are LINEAR, always o
return tonemap_aces(color, white);
#endif
- return clamp(color, vec3(0.0f), vec3(1.0f)); // no other selected -> linear
+ return color; // no other selected -> linear: no color transform applied
}
vec3 gather_glow(sampler2D tex, vec2 uv) { // sample all selected glow levels
@@ -216,10 +221,14 @@ vec3 apply_glow(vec3 color, vec3 glow) { // apply glow using the selected blendi
#endif
#ifdef USE_GLOW_SCREEN
+ //need color clamping
+ color = clamp(color, vec3(0.0f), vec3(1.0f));
color = max((color + glow) - (color * glow), vec3(0.0));
#endif
#ifdef USE_GLOW_SOFTLIGHT
+ //need color clamping
+ color = clamp(color, vec3(0.0f), vec3(1.0));
glow = glow * vec3(0.5f) + vec3(0.5f);
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)));
@@ -261,14 +270,16 @@ void main() {
color *= exposure;
- // Early Tonemap & SRGB Conversion
+ // Early Tonemap & SRGB Conversion; note that Linear tonemapping does not clamp to [0, 1]; some operations below expect a [0, 1] range and will clamp
color = apply_tonemapping(color, white);
#ifdef KEEP_3D_LINEAR
// leave color as is (-> don't convert to SRGB)
#else
- color = linear_to_srgb(color); // regular linear -> SRGB conversion
+ //need color clamping
+ color = clamp(color, vec3(0.0f), vec3(1.0f));
+ color = linear_to_srgb(color); // regular linear -> SRGB conversion (needs clamped values)
#endif
// Glow
@@ -278,6 +289,7 @@ void main() {
// high dynamic range -> SRGB
glow = apply_tonemapping(glow, white);
+ glow = clamp(glow, vec3(0.0f), vec3(1.0f));
glow = linear_to_srgb(glow);
color = apply_glow(color, glow);