Merge branch 'rgb19e7-bug' into spirv-optimizer

Author: Crisspl

examples_tests/22.RaytracedAO/main.cpp

@@ -313,4 +313,4 @@ int main()
 	renderer = nullptr;
 
 	return 0;
-}
+}

examples_tests/22.RaytracedAO/raytraceCommon.glsl

@@ -138,13 +138,13 @@ layout(set = 1, binding = 5, std430, row_major) restrict readonly buffer LightRa
 vec3 fetchAccumulation(in ivec2 coord)
 {
     const uvec2 data = imageLoad(accumulation,coord).rg;
-	return vec4(unpackHalf2x16(data[0]),unpackHalf2x16(data[1])).rgb;
-	//return nbl_glsl_decodeRGB19E7(data);
+	//return vec4(unpackHalf2x16(data[0]),unpackHalf2x16(data[1])).rgb;
+	return nbl_glsl_decodeRGB19E7(data);
 }
 void storeAccumulation(in vec3 color, in ivec2 coord)
 {
-	//const uvec2 data = nbl_glsl_encodeRGB19E7(color);
-	const uvec2 data = uvec2(packHalf2x16(color.rg),packHalf2x16(vec2(color.b,1.0)));
+	const uvec2 data = nbl_glsl_encodeRGB19E7(color);
+	//const uvec2 data = uvec2(packHalf2x16(color.rg),packHalf2x16(vec2(color.b,1.0)));
 	imageStore(accumulation,coord,uvec4(data,0u,0u));
 }
 

include/nbl/builtin/glsl/format/constants.glsl

@@ -8,9 +8,9 @@
 #define nbl_glsl_RGB19E7_EXP_BIAS 63
 #define nbl_glsl_MAX_RGB19E7_EXP (nbl_glsl_RGB19E7_EXP_BIAS+1)
 
-#define MAX_RGB19E7_MANTISSA_VALUES (0x1<<nbl_glsl_RGB19E7_MANTISSA_BITS)
-#define MAX_RGB19E7_MANTISSA (MAX_RGB19E7_MANTISSA_VALUES-1)
-#define nbl_glsl_MAX_RGB19E7 float(MAX_RGB19E7_MANTISSA)/float(MAX_RGB19E7_MANTISSA_VALUES)*exp2(float(nbl_glsl_MAX_RGB19E7_EXP-nbl_glsl_RGB19E7_MANTISSA_BITS))
+#define nbl_glsl_MAX_RGB19E7_MANTISSA_VALUES (0x1<<nbl_glsl_RGB19E7_MANTISSA_BITS)
+#define nbl_glsl_MAX_RGB19E7_MANTISSA (nbl_glsl_MAX_RGB19E7_MANTISSA_VALUES-1)
+#define nbl_glsl_MAX_RGB19E7 float(nbl_glsl_MAX_RGB19E7_MANTISSA)/float(nbl_glsl_MAX_RGB19E7_MANTISSA_VALUES)*exp2(float(nbl_glsl_MAX_RGB19E7_EXP-nbl_glsl_RGB19E7_MANTISSA_BITS))
 
 #define nbl_glsl_RGB19E7_COMPONENT_INDICES ivec4(0,0,1,1)
 #define nbl_glsl_RGB19E7_COMPONENT_BITOFFSETS ivec4(0,nbl_glsl_RGB19E7_MANTISSA_BITS,(2*nbl_glsl_RGB19E7_MANTISSA_BITS)&31,(3*nbl_glsl_RGB19E7_MANTISSA_BITS)&31)

include/nbl/builtin/glsl/format/encode.glsl

@@ -9,9 +9,14 @@ uvec2 nbl_glsl_encodeRGB19E7(in vec3 col)
 	const float maxrgb = max(max(clamped.r,clamped.g),clamped.b);
 
 	const int f32_exp = ((floatBitsToInt(maxrgb)>>23) & 0xff) - 127;
-	const int shared_exp = clamp(f32_exp,-nbl_glsl_RGB19E7_EXP_BIAS-1,nbl_glsl_MAX_RGB19E7_EXP) + 1;
-
-	const uvec3 mantissas = uvec3(clamped*exp2(nbl_glsl_RGB19E7_MANTISSA_BITS-shared_exp) + 0.5);
+	int shared_exp = clamp(f32_exp,-nbl_glsl_RGB19E7_EXP_BIAS-1,nbl_glsl_MAX_RGB19E7_EXP) + 1;
+
+	float scale = exp2(nbl_glsl_RGB19E7_MANTISSA_BITS - shared_exp);
+	const uint maxm = uint(maxrgb*scale + 0.5);
+	const bool need = (maxm == nbl_glsl_MAX_RGB19E7_MANTISSA_VALUES);
+	scale = need ? 0.5*scale : scale;
+	shared_exp = need ? (shared_exp+1) : shared_exp;
+	const uvec3 mantissas = uvec3(clamped*scale + 0.5);
 
 	uvec2 encoded;
 	encoded.x = bitfieldInsert(mantissas.x,mantissas.y,nbl_glsl_RGB19E7_COMPONENT_BITOFFSETS[1],nbl_glsl_RGB19E7_G_COMPONENT_SPLIT);