Playground: I don’t know why it cannot generate share link
from http://transitions.glsl.io/transition/b1ed2b9c435ed6d4b18c8b9fda6e4352
P\_UV float MIN\_AMOUNT = -0.16; P\_UV float MAX\_AMOUNT = 1.3; P\_UV float PI = 3.141592653589793; P\_UV float scale = 512.0; P\_UV float sharpness = 3.0; vec3 hitPoint(float hitAngle, float yc, vec3 point, mat3 rrotation) { float hitPoint = hitAngle / (2.0 \* PI); point.y = hitPoint; return rrotation \* point; } vec4 antiAlias(vec4 color1, vec4 color2, float distanc) { distanc \*= scale; if (distanc \< 0.0) return color2; if (distanc \> 2.0) return color1; float dd = pow(1.0 - distanc / 2.0, sharpness); return ((color2 - color1) \* dd) + color1; } float distanceToEdge(vec3 point) { float dx = abs(point.x \> 0.5 ? 1.0 - point.x : point.x); float dy = abs(point.y \> 0.5 ? 1.0 - point.y : point.y); if (point.x \< 0.0) dx = -point.x; if (point.x \> 1.0) dx = point.x - 1.0; if (point.y \< 0.0) dy = -point.y; if (point.y \> 1.0) dy = point.y - 1.0; if ((point.x \< 0.0 || point.x \> 1.0) && (point.y \< 0.0 || point.y \> 1.0)) return sqrt(dx \* dx + dy \* dy); return min(dx, dy); } vec4 seeThrough(vec2 resolution, float cylinderRadius, float cylinderAngle, float yc, vec2 p, mat3 rotation, mat3 rrotation) { float hitAngle = PI - (acos(yc / cylinderRadius) - cylinderAngle); vec3 point = hitPoint(hitAngle, yc, rotation \* vec3(p, 1.0), rrotation); if (yc \<= 0.0 && (point.x \< 0.0 || point.y \< 0.0 || point.x \> 1.0 || point.y \> 1.0)) { vec2 texCoord = gl\_FragCoord.xy / resolution.xy; return texture2D(CoronaSampler0 , texCoord); } if (yc \> 0.0) return texture2D(CoronaSampler1, p); vec4 color = texture2D(CoronaSampler1, point.xy); vec4 tcolor = vec4(0.0); return antiAlias(color, tcolor, distanceToEdge(point)); } vec4 seeThroughWithShadow(float amount, vec2 resolution, float cylinderRadius, float cylinderAngle, float yc, vec2 p, vec3 point, mat3 rotation, mat3 rrotation) { float shadow = distanceToEdge(point) \* 30.0; shadow = (1.0 - shadow) / 3.0; if (shadow \< 0.0) shadow = 0.0; else shadow \*= amount; vec4 shadowColor = seeThrough( resolution, cylinderRadius, cylinderAngle,yc, p, rotation, rrotation); shadowColor.r -= shadow; shadowColor.g -= shadow; shadowColor.b -= shadow; return shadowColor; } vec4 backside(float cylinderRadius, float yc, vec3 point) { vec4 color = texture2D(CoronaSampler1, point.xy); float gray = (color.r + color.b + color.g) / 15.0; gray += (8.0 / 10.0) \* (pow(1.0 - abs(yc / cylinderRadius), 2.0 / 10.0) / 2.0 + (5.0 / 10.0)); color.rgb = vec3(gray); return color; } vec4 behindSurface(vec2 resolution, float amount, float cylinderRadius, float cylinderAngle, float yc, vec3 point, mat3 rrotation) { float shado = (1.0 - ((-cylinderRadius - yc) / amount \* 7.0)) / 6.0; shado \*= 1.0 - abs(point.x - 0.5); yc = (-cylinderRadius - cylinderRadius - yc); float hitAngle = (acos(yc / cylinderRadius) + cylinderAngle) - PI; point = hitPoint(hitAngle, yc, point, rrotation); if (yc \< 0.0 && point.x \>= 0.0 && point.y \>= 0.0 && point.x \<= 1.0 && point.y \<= 1.0 && (hitAngle \< PI || amount \> 0.5)) { shado = 1.0 - (sqrt(pow(point.x - 0.5, 2.0) + pow(point.y - 0.5, 2.0)) / (71.0 / 100.0)); shado \*= pow(-yc / cylinderRadius, 3.0); shado \*= 0.5; } else { shado = 0.0; } vec2 texCoord = gl\_FragCoord.xy / resolution.xy; return vec4(texture2D(CoronaSampler0, texCoord).rgb - shado, 1.0); } P\_COLOR vec4 FragmentKernel( P\_UV vec2 texCoord ){ float progress = abs(cos(CoronaTotalTime)); float amount = progress \* (MAX\_AMOUNT - MIN\_AMOUNT) + MIN\_AMOUNT; float cylinderCenter = amount; // 360 degrees \* amount float cylinderAngle = 2.0 \* PI \* amount; float cylinderRadius = 1.0 / PI / 2.0; vec2 resolution = vec2(CoronaVertexUserData.x,CoronaVertexUserData.y); vec2 texCoord1 = gl\_FragCoord.xy / resolution.xy; float angle = 30.0 \* PI / 180.0; float c = cos(-angle); float s = sin(-angle); mat3 rotation = mat3( c, s, 0, -s, c, 0, 0.12, 0.258, 1 ); c = cos(angle); s = sin(angle); mat3 rrotation = mat3( c, s, 0, -s, c, 0, 0.15, -0.5, 1 ); vec3 point = rotation \* vec3(texCoord, 1.0); float yc = point.y - cylinderCenter; if (yc \< -cylinderRadius) { // Behind surface gl\_FragColor = behindSurface( resolution, amount, cylinderRadius, cylinderAngle, yc, point, rrotation); return CoronaColorScale( vec4(vec3(gl\_FragColor), 1.0)); } if (yc \> cylinderRadius) { // Flat surface gl\_FragColor = texture2D(CoronaSampler1 , texCoord); return CoronaColorScale( vec4(vec3(gl\_FragColor), 1.0)); } float hitAngle = (acos(yc / cylinderRadius) + cylinderAngle) - PI; float hitAngleMod = mod(hitAngle, 2.0 \* PI); if ((hitAngleMod \> PI && amount \< 0.5) || (hitAngleMod \> PI/2.0 && amount \< 0.0)) { gl\_FragColor = seeThrough( resolution, cylinderRadius, cylinderAngle,yc, texCoord, rotation, rrotation); return CoronaColorScale( vec4(vec3(gl\_FragColor), 1.0)); } point = hitPoint(hitAngle, yc, point, rrotation); if (point.x \< 0.0 || point.y \< 0.0 || point.x \> 1.0 || point.y \> 1.0) { gl\_FragColor = seeThroughWithShadow( amount, resolution, cylinderRadius, cylinderAngle, yc, texCoord, point, rotation, rrotation); return CoronaColorScale( vec4(vec3(gl\_FragColor), 1.0)); } vec4 color = backside(cylinderRadius,yc, point); vec4 otherColor; if (yc \< 0.0) { float shado = 1.0 - (sqrt(pow(point.x - 0.5, 2.0) + pow(point.y - 0.5, 2.0)) / 0.71); shado \*= pow(-yc / cylinderRadius, 3.0); shado \*= 0.5; otherColor = vec4(0.0, 0.0, 0.0, shado); } else { otherColor = texture2D(CoronaSampler1, texCoord); } color = antiAlias(color, otherColor, cylinderRadius - abs(yc)); vec4 cl = seeThroughWithShadow(amount, resolution, cylinderRadius, cylinderAngle,yc, texCoord, point, rotation, rrotation); float dist = distanceToEdge(point); gl\_FragColor = antiAlias(color, cl, dist); return CoronaColorScale( vec4(vec3(gl\_FragColor), 1.0)); }