From 3983cbd732d09c46afae8e3cfde9427aa68d672b Mon Sep 17 00:00:00 2001
From: saschawillems <webmaster@saschawillems.de>
Date: Tue, 1 Nov 2016 15:39:54 +0100
Subject: [PATCH] Set SSAO shader constants via specialization

---
 data/shaders/ssao/ssao.frag     |  24 ++++++++++++++----------
 data/shaders/ssao/ssao.frag.spv | Bin 5140 -> 5236 bytes
 ssao/ssao.cpp                   |  20 +++++++++++++++++---
 3 files changed, 31 insertions(+), 13 deletions(-)

diff --git a/data/shaders/ssao/ssao.frag b/data/shaders/ssao/ssao.frag
index 8380f733..4c78d681 100644
--- a/data/shaders/ssao/ssao.frag
+++ b/data/shaders/ssao/ssao.frag
@@ -7,9 +7,12 @@ layout (binding = 0) uniform sampler2D samplerPositionDepth;
 layout (binding = 1) uniform sampler2D samplerNormal;
 layout (binding = 2) uniform sampler2D ssaoNoise;
 
+layout (constant_id = 0) const int SSAO_KERNEL_SIZE = 64;
+layout (constant_id = 1) const float SSAO_RADIUS = 0.5;
+
 layout (binding = 3) uniform UBOSSAOKernel
 {
-	vec4 samples[64]; // todo: specialization const
+	vec4 samples[SSAO_KERNEL_SIZE];
 } uboSSAOKernel;
 
 layout (binding = 4) uniform UBO 
@@ -21,10 +24,6 @@ layout (location = 0) in vec2 inUV;
 
 layout (location = 0) out float outFragColor;
 
-// todo: specialization const
-const int kernelSize = 32;
-const float radius = 0.5;
-
 void main() 
 {
 	// Get G-Buffer values
@@ -35,7 +34,7 @@ void main()
 	ivec2 texDim = textureSize(samplerPositionDepth, 0); 
 	ivec2 noiseDim = textureSize(ssaoNoise, 0);
 	const vec2 noiseUV = vec2(float(texDim.x)/float(noiseDim.x), float(texDim.y)/(noiseDim.y)) * inUV;  
-	vec3 randomVec = texture(ssaoNoise, noiseUV).xyz;
+	vec3 randomVec = texture(ssaoNoise, noiseUV).xyz * 2.0 - 1.0;
 	
 	// Create TBN matrix
 	vec3 tangent = normalize(randomVec - normal * dot(randomVec, normal));
@@ -44,10 +43,10 @@ void main()
 
 	// Calculate occlusion value
 	float occlusion = 0.0f;
-	for(int i = 0; i < kernelSize; i++)
+	for(int i = 0; i < SSAO_KERNEL_SIZE; i++)
 	{		
 		vec3 samplePos = TBN * uboSSAOKernel.samples[i].xyz; 
-		samplePos = fragPos + samplePos * radius; 
+		samplePos = fragPos + samplePos * SSAO_RADIUS; 
 		
 		// project
 		vec4 offset = vec4(samplePos, 1.0f);
@@ -57,11 +56,16 @@ void main()
 		
 		float sampleDepth = -texture(samplerPositionDepth, offset.xy).w; 
 
+#define RANGE_CHECK 1
+#ifdef RANGE_CHECK
 		// Range check
-		float rangeCheck = smoothstep(0.0f, 1.0f, radius / abs(fragPos.z - sampleDepth));
+		float rangeCheck = smoothstep(0.0f, 1.0f, SSAO_RADIUS / abs(fragPos.z - sampleDepth));
 		occlusion += (sampleDepth >= samplePos.z ? 1.0f : 0.0f) * rangeCheck;           
+#else
+		occlusion += (sampleDepth >= samplePos.z ? 1.0f : 0.0f);  
+#endif
 	}
-	occlusion = 1.0 - (occlusion / float(kernelSize));
+	occlusion = 1.0 - (occlusion / float(SSAO_KERNEL_SIZE));
 	
 	outFragColor = occlusion;
 }
diff --git a/data/shaders/ssao/ssao.frag.spv b/data/shaders/ssao/ssao.frag.spv
index 241fd0607fbed0251253e4252940b4371fadd5a3..e8009057ed5e1004405b86bbc0a3039e875e80f8 100644
GIT binary patch
literal 5236
zcmZ{mi<ebp8HYCvGXsGlp{Qv(Kt-hzBASH?0|b;bj3SVl4u_e|aCGME!#QUPq;k|O
z%}d_WE>>2WT3MNR%S)zq^=|zw-PUTYo@bx$tu1Tyv3|Vo`+KkZ`@X%;^vqn^pJg-n
zH#_@l)?Ev-nb=vTT#1~U^_BLfE!(y%Z+FI)uR3#ukw<1diqbbf>(6GPi^*EOA-@2;
z4UQsCo<?XrRL!y%X)r6BlWp2EGI-&-k#^p!wQ8Mwq`kK`mbXTV-B;wJo%TCpaMc^*
zBNMg8_*88?A6d0>MYA?~W!6ijYG3U+^w`s?jSm-X{Ijzou-moC=0x6ts(0!|V?*BT
z?1e7#oweTBz9Z~KD2<{uS)0(`mmQ0p@`n;#=Di=jlkeY9pERyF`*4|8Z|5b`<xVlT
zT`PtPcy#A;0~^}3G;bqztJWARCU@kcDP{=S;bHSer;OQ&y}KTab$YVP;4WG>RQj9f
z#pvk7RGX(m*S`;0FZJH+AhP=m?u!1t>`Tb)>$Yy&Hn{ctyw%8gT-e@{M@{kWVP7_l
zJ+-@dN373s3w*I>Pdo2)d)|djO)~m2byu@hc%tQC&UH5&wW!;hJ%Zkyt9vAJhv3+c
z@qGQ>oFgv#dzXr-&PI-PeKAqAFtbhc_iUGFu)<#4HA~yGJ*i@QmeqJ|<Gu6ddtOz)
zwtnxe{{2W}UD{tn_JO0oW+rt{T}!)yn4Xf0{Au`VeQoReHd*gRr1iyS?AXKJ((e7Q
z9rf)QF}`EYVNbc}>3&yxYTMKI#-8qN?9oE9%v($iXHs8;<}(g}V~Mwqw*CR^*+@BY
zJa6B-kotXw>I(Y=GUwtj&ir{PNN#nqJy)0g<|D1=EXMnc){-|~+jEvPej(C$pD*fp
z&aP8n^_^H++1jwX&p*B982s+l0El|-wOsUnAG*&fZ@#`|z!m+xH!kP>2-0}xwf^ZP
z&wniQwO5u_H~tKC<E<P1)#%Q19PyVT^~e5yHrev=JT-Ke{R^b=KKDv&>w1sZf}?q=
z1IQEMz02;MzLTi#U6!-P)ySDZ&S%t~26FnZO}hE^u$On4wMPHVD9)hYXSg%zo{_!0
zuX4tI18H43due-Tqt`u2H$L{~UUc^(p8r8~)|&7?j$yv`667mj2C&~-NOPUpe%ihh
za%b^=ndh7?xqra;J{s%Y_xHwU3wu$;_OAFl5q@odC&Kn_tf<)5+jyAmZ$ZTC-&wIe
zdw&PQ?^!o1_8I8=Dz^Fl7DT+~;x{~O^Zh1Q?L&vz&n5d@p5J%&NZ|XbJs<gQumJ32
zmlh(A2FA#5Wyh?243HNt&%%8^j~#YD^+)~V(0zZS{_*J5`tQLuMn3AFfG#gwQU6wE
zvj2O5F@6VzIeEF0f!~3^bt!fL&UpRvQtV=MYkmR@0O$7H<zwy-pt~<)?2F&J4+6Py
z>MlioC~?b>=6g@%BL7r$zax=<8oFHMFGrV)eD9UqAoV@>Rlu5lTde85KNH9o*xvWE
z5*Ili#kNj0=WJ~G$oUw$+zs@x#>atm<fG0x==NR>qW8Jz@=@o!()YidHQ4s9=B&k*
zkDNhtx#+zP-8%Ba%;WuA51dJ#z2!Cl@67cn#&a`H-o5u7l#9LJgznx){$_Mz;!b}O
z-5B|}bDu(&7p@s#CWt$CKDsg0JGTWp?wd01+^5lv*YA8Ak#f${kK796!X8HV{)K(P
zVg3t~|E_dq+pvw1kNGY_w~oG;V>`ON^u^uZf$p=pU;3SI2q_=^KZ7n8_QmMVH;?I^
z{}Nyg_up9k*74h>FY+!&uhtpCHYWVL(5-txdam8*=D30zMVGT*aAS${e1gl-t?vqM
z54v16cRX>`+`VwSfGcwA=(|8Q_lm@s8{eHP(Vg2loh$eWbZ2q~dj>y=Za?c=PySM5
z16a#EW8BZnkn-wHWG(6Ykjub7xuGqjziG<9albmqDd5uoIi!B2`@RJEd0>r4+4lp;
zs}i>#`7dI$+rV1ps+;SaUjWV(wXQ+8)*#PuE%G`r4V+J(aSM@O2KwTCyFPL9F8A4e
zy`7o*kzWD!GS25em^ka{|0<XR!oC6Bn0Oz)hAwv_xF*%S3Eez>QBy8z+=_0ExC38D
zmvaSo8@inH26ubnoPU_<eBL{N`Nr$_`(V#okox@A-h=!mxEm}3&T%L5TR>jhTHgld
zxi{M10mjHjO*v~8$nOH<?*-QALw*m)N6qh}8x!YoAG(}y#d*ZN{Q;ac0)E3ihaZCb
zfc~icBlK?VIpw_fW6K#k3-khK>H#soF_HfOdUduRW6KFw%ob<;5S%d&f|&Q=WXp-T
z13y7GUVrraDSCC@pJB@x`~T)O#{9X+pMxWk?fLuybnEq(zhA#hoV?5V<G1Khbn}gg
z`}8YxdH3h)bbgPa%e!BXAhqMXpFsCrcpNyBd;27i5Bn)}^Zael|1>a0-rokfUjt|J
znf1r-^fTzbNBZaSH=wc40%K1HHQ@a=&iM`@^+)gL(d`}c{s#RZsLuNWw*2$VcL4d@
zQqQs%kbkG<OGuaBCw(u1mx13Wb^AVtbPm6J#_KaCe9l?*851-94&D5)e~<2S_&0~o
z`v+i*e8l__y$QTq#{3D$8Ea2{a`yC_>^w^ImmvQP_JL{gwO>u#D@gP8$(i3mn(sF`
v`oD&5kNErQb@crp&g~6!W8~x9-$Zwh^u>&FQS&e8*3|blQv2VW^x5D)G8D@R

literal 5140
zcmZ{mi<ebp8HYCvGs6g82(M{0Kt+iXBAP`CGayh9jB?SuFdk+$!_k?u$8*jQ-4r#`
z#2boT>}K~Ot+0#N%+$)VLjRdk*K)0%XP@uY?X1<u`tiQ+@4fEt`}RK5HFI%qmd)Vb
z?CiCyv*u+pv9nCM0y!t^DeVoLw{2e5YL6~kdBJicPsq9yrSHV7H=BhnCTjJD{5)_B
zoJ5>FjnKNNnq@E0U{=<bZP+|KaQWbHE1#@2YwdivwYN5!H;0Se*XJYc*1KbH)f;2O
z<F&@vRBbFDUb$lVWNqYzteZ;JzS@2C*wd_y4HYf?v$Nx|TeXSF@w^FDZ`X^)x_q*|
z7rM-M)_P;d&ah8KX%x+g+PMCn>@@6@za`OS-Us2^`TlkF3FEr6v&+1CD=(Q2x76HL
zt=Lk)qdT7)*wCh>dF!#8wZ>>Mu`?e@F`JNW9yV{Z%b4xhyX(PNrz^V(Zu{Vt($5H4
zF)}hf)#B;U^(*V8-kt47cAmjq(chDO3Atl%>$YtJTQ}v+M$Y5Hc9%SAigyotvYW7{
zb{Fr8^;r(W7kl=!@^+`^1K89gqbE~$O*RWpv>eR24#QE4y4~3k^v+zJBau4_$9|0E
zYxm|HaoOLyR7|zkbF6EN@uG>DZJ@tryGVl-_QH-?+Mex#itSle<F$?V&YSOfRsGuf
zy|?<mi0lC;fsIV&9=aBH1TkGD7xC^}wVt;1e0w%hFZQUrw7cK7qn<q?#&^iR_K=Gn
z?q{`!wmp0=oY}pLJ(y3Hc?+rG4C<$%`Aq%bG~(@}t-l|8Hd0QU!P|8lQvVE4U16U|
z<{TWxnLjrL$*oGZ=jO8CiAd`?i}60Awd9T0_8jGmpN}-&=ZkutqiZRwzOzazTN8HY
z`46l<1;2aM52BuXEf@VifbO%(o3C#Pa791wh0A$AiZtGNt$$w0^B>E6?G>ffi9a9R
zc<Y9L6}t1BPW+Wf{jvX_O}2bI&n|SA{e5qZ_qk)<snVBaC-YSM67L*e0BgWm<aw9f
zOSuJf^DfI-^UFy0L(XT`_U_8*Kah0uW2QUMS*!Kmh2l*5eWpW6_ss0&{gpHJL8Nu%
z?4|7;j$RKX-T2tAhtb`iupdt`@%%4i&q#jv<rTmhwBNr`%$2vF_OZlW$opnr=X4qO
zI*jk9vAzrbzW8im`+E_#cgNp_s(p6F_O2|i*w$M=&E7Q4-d?f23x4;bzGv^ZKkW0-
z{qBcteZT!-doBknw)sb<*+-|@Pbd3go_`Md3BdPP+dKarFb`b8E_vQ317qa3vSao>
z1;`7RXX8F!!VbHi`lJ5o=)TWU{|xkM{r6%UBOmq8M3)z?sDCdr+5dgO7{3ccoV?uo
zf!~F|Z7H@N&UpQEQ|v-?YhDWafpdHA@-g>^(A}3&_T@O_hk@J}br&N)lDH*E^Svi>
zk$(>QQV{v)qRU18GIY7f_g={jP~UT339PvSSaT8b0w7;td*3fiT;zNV+d9>pi?HP*
z=i}&dchbiip8(d8k2;@3xA!U#y)Q<Wk2;r>zISp~W81r$vj$r}at6@lqW2)Wb>xSb
z$NRSyIFmkm%dG?6ncGv0=VqL|d+$3a7kj?}-Mx?ejp)Y2o&FTMG4gTeK8-FfTr<E-
zVEy$-{nqP6ZU%B;e+J$A6ZV#A{;kP>IPLimwlVT?r!Padj=s3Nm!sQDU)<eo=+5Tz
z>UX|PNcrf$16?lco#@Utm+77V3SbTQ&shD|*^bl~c~_%X>s*6vO!%)wx9(->xrWir
zaRqlBx}5!jt0m6;4Q@BO^<BY@pvzTrM-x}g&EcHI6}fxR<*K=3i8D988+*~6`#RuU
z!Pn89$r<b!{PpPev%dA@uSDJetYw}t?&noVdG!h8uB11ROTZi4umb6ClJY;?uN#p~
z;L_hh>Q}n&i;!(#jic=QKIG>TH-&tY80|@5Epye)b<WQN=Zac4qg!i$=Qx181>6Lj
zPoHt~k+%YU@xI)aIC+=*JQEyZre5S%fW3_K`S&Nzdirk%eIV?wq8k(M!=31IcYs?`
z&99-Gr!Q*CMUA`Btr2(N9&|ZZaQC9iId5?HCC>SWn9k?DADC~v{sq9E2a)>xRz8IM
zIyem6FXuRf{05NMw$?X+dG3w&w}3J7QB%&E<H&CV;~xgr=s|u5$VbiZq8k(E@jY}o
z;fnK!d;5JjYXtlTdk&8PbM;5<AE0+?_m%Vh5L@mMFbi}8XX*kmzcG>jBlPNQKgO05
zu9z*(`X_M4c-ArRPm?Vt;tu=_-FW@c@8{^%d4GW|XYBu**BJBXAb$ytPqydtDCpGd
zEq{L=OPsvR`Qx|bSLo&&6Zh%Y=<@E*&FTDpgD&rW9YJcxdH)u@4?GT>$-Vs@kPrL!
z=;ry`p#KlR7<qpi<emV|<}>S$-`OY8-9!Cz`5VsIr+~5NfnC7+ZJhHRMe2{<&!F2o
z=6x1@Kd8?8M{N1$m~USxv&=mC|5EdLq|5KqbI3n|KLfu{>h^sa=^TFdo=564CVb9W
z^%)a0zJP9i*e{~{9RAJV^S%U(k&l?apicnrmN9<?a>m+IpPW7YCOePP{6)yWfd)80
zzV_b}_cGFaeRAd(Nb_$*M*n}H+au2DpXhS0fH>!Wp}QygVkWt$@hZAC^c_QLzs1R3
G1pWu(u)x3o

diff --git a/ssao/ssao.cpp b/ssao/ssao.cpp
index 337adef4..51b2d9a9 100644
--- a/ssao/ssao.cpp
+++ b/ssao/ssao.cpp
@@ -25,6 +25,7 @@
 #define ENABLE_VALIDATION false
 
 #define SSAO_KERNEL_SIZE 32
+#define SSAO_RADIUS 0.5f
 
 #if defined(__ANDROID__)
 #define SSAO_NOISE_DIM 8
@@ -948,9 +949,22 @@ public:
 		// SSAO Pass
 		shaderStages[0] = loadShader(getAssetPath() + "shaders/ssao/fullscreen.vert.spv", VK_SHADER_STAGE_VERTEX_BIT);
 		shaderStages[1] = loadShader(getAssetPath() + "shaders/ssao/ssao.frag.spv", VK_SHADER_STAGE_FRAGMENT_BIT);
-		pipelineCreateInfo.renderPass = frameBuffers.ssao.renderPass;
-		pipelineCreateInfo.layout = pipelineLayouts.ssao;
-		VK_CHECK_RESULT(vkCreateGraphicsPipelines(device, pipelineCache, 1, &pipelineCreateInfo, nullptr, &pipelines.ssao));
+		{
+			// Set constant parameters via specialization constants
+			std::array<VkSpecializationMapEntry, 2> specializationMapEntries;
+			specializationMapEntries[0] = vkTools::initializers::specializationMapEntry(0, 0, sizeof(uint32_t));				// SSAO Kernel size
+			specializationMapEntries[1] = vkTools::initializers::specializationMapEntry(1, sizeof(uint32_t), sizeof(float));	// SSAO radius
+			struct {
+				uint32_t kernelSize = SSAO_KERNEL_SIZE;
+				float radius = SSAO_RADIUS;
+			} specializationData;
+			VkSpecializationInfo specializationInfo = vkTools::initializers::specializationInfo(2, specializationMapEntries.data(), sizeof(specializationData), &specializationData);
+			shaderStages[1].pSpecializationInfo = &specializationInfo;
+			pipelineCreateInfo.renderPass = frameBuffers.ssao.renderPass;
+			pipelineCreateInfo.layout = pipelineLayouts.ssao;
+			VK_CHECK_RESULT(vkCreateGraphicsPipelines(device, pipelineCache, 1, &pipelineCreateInfo, nullptr, &pipelines.ssao));
+		}
+
 
 		// SSAO blur pass
 		shaderStages[0] = loadShader(getAssetPath() + "shaders/ssao/fullscreen.vert.spv", VK_SHADER_STAGE_VERTEX_BIT);