1 #ifndef IS_REQUIRED_ROUNDED_CORNER
2 #define IS_REQUIRED_ROUNDED_CORNER 0
4 #ifndef IS_REQUIRED_BORDERLINE
5 #define IS_REQUIRED_BORDERLINE 0
7 #ifndef IS_REQUIRED_BLUR
8 #define IS_REQUIRED_BLUR 0
11 #if IS_REQUIRED_ROUNDED_CORNER || IS_REQUIRED_BORDERLINE || IS_REQUIRED_BLUR
12 INPUT mediump vec2 vPosition;
13 INPUT mediump vec2 vRectSize;
14 INPUT mediump vec2 vOptRectSize;
15 #if IS_REQUIRED_ROUNDED_CORNER
16 INPUT mediump vec4 vCornerRadius;
20 uniform lowp vec4 uColor;
21 uniform lowp vec3 mixColor;
22 #if !IS_REQUIRED_BLUR && IS_REQUIRED_BORDERLINE
23 uniform mediump float borderlineWidth;
24 uniform mediump float borderlineOffset;
25 uniform lowp vec4 borderlineColor;
26 uniform lowp vec4 uActorColor;
29 uniform mediump float blurRadius;
33 #if IS_REQUIRED_ROUNDED_CORNER || IS_REQUIRED_BORDERLINE || IS_REQUIRED_BLUR
34 // Global values both rounded corner and borderline use
36 // radius of rounded corner on this quadrant
37 mediump float gRadius = 0.0;
39 // fragment coordinate. NOTE : vec2(0.0, 0.0) is vRectSize, the corner of visual
40 mediump vec2 gFragmentPosition = vec2(0.0, 0.0);
41 // center coordinate of rounded corner circle. vec2(gCenterPosition, gCenterPosition).
42 mediump float gCenterPosition = 0.0;
43 // relative coordinate of gFragmentPosition from gCenterPosition.
44 mediump vec2 gDiff = vec2(0.0, 0.0);
45 // potential value what our algorithm use.
46 mediump float gPotential = 0.0;
48 // threshold of potential
49 mediump float gPotentialRange = 0.0;
50 mediump float gMaxOutlinePotential = 0.0;
51 mediump float gMinOutlinePotential = 0.0;
52 mediump float gMaxInlinePotential = 0.0;
53 mediump float gMinInlinePotential = 0.0;
55 void calculateCornerRadius()
57 #if IS_REQUIRED_ROUNDED_CORNER
60 mix(vCornerRadius.x, vCornerRadius.y, sign(vPosition.x) * 0.5 + 0.5),
61 mix(vCornerRadius.w, vCornerRadius.z, sign(vPosition.x) * 0.5 + 0.5),
62 sign(vPosition.y) * 0.5 + 0.5
67 void calculatePosition()
69 gFragmentPosition = abs(vPosition) - vRectSize;
70 gCenterPosition = -gRadius;
71 #if !IS_REQUIRED_BLUR && IS_REQUIRED_BORDERLINE
72 gCenterPosition += borderlineWidth * (clamp(borderlineOffset, -1.0, 1.0) + 1.0) * 0.5;
74 gDiff = gFragmentPosition - gCenterPosition;
77 void calculatePotential()
79 gPotential = length(max(gDiff, 0.0)) + min(0.0, max(gDiff.x, gDiff.y));
82 void setupMinMaxPotential()
84 gPotentialRange = 1.0;
86 gMaxOutlinePotential = gRadius + gPotentialRange;
87 gMinOutlinePotential = gRadius - gPotentialRange;
89 #if !IS_REQUIRED_BLUR && IS_REQUIRED_BORDERLINE
90 gMaxInlinePotential = gMaxOutlinePotential - borderlineWidth;
91 gMinInlinePotential = gMinOutlinePotential - borderlineWidth;
93 gMaxInlinePotential = gMaxOutlinePotential;
94 gMinInlinePotential = gMinOutlinePotential;
97 // reduce defect near edge of rounded corner.
98 gMaxOutlinePotential += clamp(-min(gDiff.x, gDiff.y)/ max(1.0, gRadius) , 0.0, 1.0);
99 gMinOutlinePotential += clamp(-min(gDiff.x, gDiff.y)/ max(1.0, gRadius) , 0.0, 1.0);
102 void PreprocessPotential()
104 calculateCornerRadius();
106 calculatePotential();
108 setupMinMaxPotential();
112 #if !IS_REQUIRED_BLUR && IS_REQUIRED_BORDERLINE
113 lowp vec4 convertBorderlineColor(lowp vec4 textureColor)
115 mediump float potential = gPotential;
117 // default opacity of borderline is 0.0
118 mediump float borderlineOpacity = 0.0;
120 // calculate borderline opacity by potential
121 if(potential > gMinInlinePotential)
123 // potential is inside borderline range.
124 borderlineOpacity = smoothstep(gMinInlinePotential, gMaxInlinePotential, potential);
127 lowp vec3 BorderlineColorRGB = borderlineColor.rgb * uActorColor.rgb;
128 lowp float BorderlineColorAlpha = borderlineColor.a * uActorColor.a;
130 //calculate inside of borderline when outilneColor.a < 1.0
131 if(borderlineColor.a < 1.0)
133 mediump float tCornerRadius = -gCenterPosition;
134 mediump float MaxTexturelinePotential = tCornerRadius + gPotentialRange;
135 mediump float MinTexturelinePotential = tCornerRadius - gPotentialRange;
136 if(potential > MaxTexturelinePotential)
138 // potential is out of texture range. use borderline color instead of texture
139 textureColor = vec4(BorderlineColorRGB, 0.0);
141 else if(potential > MinTexturelinePotential)
143 // potential is in texture range
144 textureColor = mix(textureColor, vec4(BorderlineColorRGB, 0.0), smoothstep(MinTexturelinePotential, MaxTexturelinePotential, potential));
146 // TODO : need to fix here when uColor.a = 0.0 and uActorColor.a != 0
147 borderlineOpacity *= borderlineColor.a;
148 return mix(textureColor, vec4(BorderlineColorRGB, 1.0), borderlineOpacity);
150 return mix(textureColor, vec4(BorderlineColorRGB, BorderlineColorAlpha), borderlineOpacity);
154 #if !IS_REQUIRED_BLUR && IS_REQUIRED_ROUNDED_CORNER
155 mediump float calculateCornerOpacity()
157 mediump float potential = gPotential;
159 // default opacity is 1.0
160 mediump float opacity = 1.0;
162 // calculate borderline opacity by potential
163 if(potential > gMaxOutlinePotential)
165 // potential is out of borderline range. just discard here
168 else if(potential > gMinOutlinePotential)
170 opacity = 1.0 - smoothstep(gMinOutlinePotential, gMaxOutlinePotential, potential);
177 mediump float calculateBlurOpacity()
179 // Don't use borderline!
180 mediump vec2 v = gDiff;
181 mediump float cy = gRadius + blurRadius;
182 mediump float cr = gRadius + blurRadius;
184 #if IS_REQUIRED_ROUNDED_CORNER
185 // This routine make perfect circle. If corner radius is not exist, we don't consider prefect circle.
186 cy = min(cy, min(vRectSize.x, vRectSize.y) - gRadius);
188 v = vec2(min(v.x, v.y), max(v.x, v.y));
191 mediump float potential = 0.0;
192 mediump float alias = min(gRadius, 1.0);
193 mediump float potentialMin = cy + gRadius - blurRadius - alias;
194 mediump float potentialMax = cy + gRadius + blurRadius + alias;
196 // move center of circles for reduce defact
197 mediump float cyDiff = min(cy, 0.2 * blurRadius);
201 mediump float diffFromBaseline = cy * v.y - (cy + cr) * v.x;
203 if(diffFromBaseline > 0.0)
205 // out of calculation bound.
208 // for anti-alias when blurRaidus = 0.0
209 mediump float heuristicBaselineScale = max(1.0 , cr * (cr + cy));
210 mediump float potentialDiff = min(alias, diffFromBaseline / heuristicBaselineScale);
211 potentialMin += potentialDiff;
212 potentialMax -= potentialDiff;
216 // get some circle centered (x, x) and radius (r = cr / cy * x)
217 // s.t. point v is on that circle
218 // highest point of that circle is (x, x + r) and potential is x + r
220 // solve (v.x - x)^2 + (v.y - x)^2 = (cr / cy * x)^2
221 #if IS_REQUIRED_ROUNDED_CORNER
222 // NOTE : lowspec HW cannot calculate here. need to reduce numeric error
223 mediump float A = (cr * cr - 2.0 * cy * cy);
224 mediump float B = cy * (v.x + v.y);
225 mediump float V = dot(v,v);
226 mediump float D = B * B + A * V;
227 potential = V * (cr + cy) / (sqrt(D) + B);
229 // We can simplify this value cause cy = 0.8 * blurRadius, cr = 1.2 * blurRadius
230 // potential = 5.0*(sqrt(4.0*(v.x+v.y)^2 + dot(v,v)) - 2.0*(v.x+v.y));
231 // = 10.0*(v.x+v.y) * (sqrt(1.0 + (length(v) / (2.0*(v.x+v.y)))^2) - 1.0);
232 // = 10.0*(v.x+v.y) * (sqrt(1.25 - x + x^2) - 1.0);
233 // ~= 10.0*(v.x+v.y) * (0.11803399 - 0.44721360x + 0.35777088x^2 - 0.14310x^3 + O(x^4)) (Taylor series)
234 // ~= -1.0557281 * (v.x + v.y) + 2.236068 * length(v) - ~~~ (here, x <= 0.5 * (1.0 - sqrt(0.5)) < 0.1464467)
235 // Note : This simplify need cause we should use it on lowspec HW.
236 mediump float x = 0.5 * (1.0 - length(v) / (v.x + v.y));
237 potential = -1.0557281 * (v.x + v.y) + 2.236068 * length(v) + 10.0 * (v.x + v.y) * (0.35777088 - 0.14310 * x) * x * x;
241 return 1.0 - smoothstep(potentialMin, potentialMax, potential);
247 lowp vec4 targetColor = vec4(mixColor, 1.0) * uColor;
249 #if IS_REQUIRED_BLUR || IS_REQUIRED_ROUNDED_CORNER || IS_REQUIRED_BORDERLINE
250 // skip most potential calculate for performance
251 if(abs(vPosition.x) < vOptRectSize.x && abs(vPosition.y) < vOptRectSize.y)
253 OUT_COLOR = targetColor;
256 PreprocessPotential();
259 #if !IS_REQUIRED_BLUR && IS_REQUIRED_BORDERLINE
260 targetColor = convertBorderlineColor(targetColor);
262 OUT_COLOR = targetColor;
265 mediump float opacity = calculateBlurOpacity();
266 OUT_COLOR.a *= opacity;
267 #elif IS_REQUIRED_ROUNDED_CORNER
268 mediump float opacity = calculateCornerOpacity();
269 OUT_COLOR.a *= opacity;