/**************************************************************************** ** ** Copyright (C) 2012 Digia Plc and/or its subsidiary(-ies). ** Contact: http://www.qt-project.org/legal ** ** This file is part of the Qt Mobility Components. ** ** $QT_BEGIN_LICENSE:LGPL$ ** Commercial License Usage ** Licensees holding valid commercial Qt licenses may use this file in ** accordance with the commercial license agreement provided with the ** Software or, alternatively, in accordance with the terms contained in ** a written agreement between you and Digia. For licensing terms and ** conditions see http://qt.digia.com/licensing. For further information ** use the contact form at http://qt.digia.com/contact-us. ** ** GNU Lesser General Public License Usage ** Alternatively, this file may be used under the terms of the GNU Lesser ** General Public License version 2.1 as published by the Free Software ** Foundation and appearing in the file LICENSE.LGPL included in the ** packaging of this file. Please review the following information to ** ensure the GNU Lesser General Public License version 2.1 requirements ** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html. ** ** In addition, as a special exception, Digia gives you certain additional ** rights. These rights are described in the Digia Qt LGPL Exception ** version 1.1, included in the file LGPL_EXCEPTION.txt in this package. ** ** GNU General Public License Usage ** Alternatively, this file may be used under the terms of the GNU ** General Public License version 3.0 as published by the Free Software ** Foundation and appearing in the file LICENSE.GPL included in the ** packaging of this file. Please review the following information to ** ensure the GNU General Public License version 3.0 requirements will be ** met: http://www.gnu.org/copyleft/gpl.html. ** ** ** $QT_END_LICENSE$ ** ****************************************************************************/ import QtQuick 2.0 Effect { divider: false parameters: ListModel { ListElement { name: "extent" value: 0.5 } } // Transform slider values, and bind result to shader uniforms property real curlExtent: 1.0 - parameters.get(0).value fragmentShaderSrc: "uniform float dividerValue; uniform float curlExtent; uniform sampler2D source; uniform lowp float qt_Opacity; varying vec2 qt_TexCoord0; const float minAmount = -0.16; const float maxAmount = 1.3; const float PI = 3.141592653589793; const float scale = 512.0; const float sharpness = 3.0; const vec4 bgColor = vec4(1.0, 1.0, 0.8, 1.0); float amount = curlExtent * (maxAmount - minAmount) + minAmount; float cylinderCenter = amount; // 360 degrees * amount float cylinderAngle = 2.0 * PI * amount; const float cylinderRadius = 1.0 / PI / 2.0; 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 distance) { distance *= scale; if (distance < 0.0) return color2; if (distance > 2.0) return color1; float dd = pow(1.0 - distance / 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(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)) return bgColor; if (yc > 0.0) return texture2D(source, p); vec4 color = texture2D(source, point.xy); vec4 tcolor = vec4(0.0); return antiAlias(color, tcolor, distanceToEdge(point)); } vec4 seeThroughWithShadow(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(yc, p, rotation, rrotation); shadowColor.r -= shadow; shadowColor.g -= shadow; shadowColor.b -= shadow; return shadowColor; } vec4 backside(float yc, vec3 point) { vec4 color = texture2D(source, 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; } void main(void) { const 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(qt_TexCoord0, 1.0); float yc = point.y - cylinderCenter; vec4 color = vec4(1.0, 0.0, 0.0, 1.0); if (yc < -cylinderRadius) { // See through to background color = bgColor; } else if (yc > cylinderRadius) { // Flat surface color = texture2D(source, qt_TexCoord0); } else { 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)) { color = seeThrough(yc, qt_TexCoord0, rotation, rrotation); } else { point = hitPoint(hitAngle, yc, point, rrotation); if (point.x < 0.0 || point.y < 0.0 || point.x > 1.0 || point.y > 1.0) { color = seeThroughWithShadow(yc, qt_TexCoord0, point, rotation, rrotation); } else { color = backside(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(source, qt_TexCoord0); } color = antiAlias(color, otherColor, cylinderRadius - abs(yc)); // This second antialiasing step causes the shader to fail to render, on // Symbian devices (tested so far using IVE3.5). Running out of scratch // memory? } } } gl_FragColor = qt_Opacity * color; }" }