2 // Copyright (c) 2014 Samsung Electronics Co., Ltd.
4 // Licensed under the Flora License, Version 1.0 (the License);
5 // you may not use this file except in compliance with the License.
6 // You may obtain a copy of the License at
8 // http://floralicense.org/license/
10 // Unless required by applicable law or agreed to in writing, software
11 // distributed under the License is distributed on an AS IS BASIS,
12 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 // See the License for the specific language governing permissions and
14 // limitations under the License.
17 #include <dali-toolkit/public-api/shader-effects/page-turn-book-spine-effect.h>
28 const std::string SHADOW_WIDTH_PROPERTY_NAME("uShadowWidth");
29 const std::string SPINE_SHADOW_PARAMETER_PROPERTY_NAME("uSpineShadowParameter");
30 const std::string IS_BACK_IMAGE_VISIBLE_PROPERTY_NAME( "uIsBackImageVisible" );
31 const std::string PAGE_WIDTH_PROPERTY_NAME( "uPageWidth" );
33 // fake shadow is used to enhance the effect, with its default maximum width to be pageSize * 0.15
34 const float DEFAULT_SHADOW_WIDTH(0.15f);
36 // the major&minor radius (in pixels) to form an ellipse shape
37 // the top-left quarter of this ellipse is used to calculate spine normal for simulating shadow
38 const Vector2 DEFAULT_SPINE_SHADOW_PARAMETER(50.0f, 20.0f);
42 PageTurnBookSpineEffect::PageTurnBookSpineEffect()
46 PageTurnBookSpineEffect::PageTurnBookSpineEffect( ShaderEffect handle )
47 : ShaderEffect( handle )
51 PageTurnBookSpineEffect::~PageTurnBookSpineEffect()
55 PageTurnBookSpineEffect PageTurnBookSpineEffect::New()
57 std::string vertexSource(
58 "uniform float uShadowWidth;\n"
61 " gl_Position = uProjection * uModelView * vec4(aPosition, 1.0);\n"
62 " vTexCoord.x = (aTexCoord.x-sTextureRect.s) /( 1.0 - uShadowWidth ) + sTextureRect.s;\n"
63 " vTexCoord.y = ( aTexCoord.y-sTextureRect.t-0.5*uShadowWidth*(sTextureRect.q-sTextureRect.t) )/( 1.0 - uShadowWidth ) + sTextureRect.t;\n"
66 // the simplified version of the fragment shader of page turn effect
67 std::string fragmentSource(
68 "uniform float uIsBackImageVisible;\n"
69 "uniform float uPageWidth;\n"
70 "uniform vec2 uSpineShadowParameter;\n"
73 // leave the border for display shadow, not visible( out of the screen ) when the page is static
74 " if( vTexCoord.y > sTextureRect.q || vTexCoord.y < sTextureRect.t || vTexCoord.x > sTextureRect.p )\n"
76 " gl_FragColor = vec4( 0.0 );\n"
80 // flip the image horizontally by changing the x component of the texture coordinate
81 " if( uIsBackImageVisible == 1.0 ) gl_FragColor = texture2D( sTexture, vec2( sTextureRect.p+sTextureRect.s-vTexCoord.x, vTexCoord.y ) ) * uColor; \n"
82 " else gl_FragColor = texture2D( sTexture, vTexCoord ) * uColor;\n"
84 // display book spine, a stripe of shadowed texture
85 " float pixelPos = (vTexCoord.x-sTextureRect.s)*uPageWidth; \n"
86 " if(pixelPos < uSpineShadowParameter.x) \n"
88 " float x = pixelPos - uSpineShadowParameter.x;\n"
89 " float y = sqrt( uSpineShadowParameter.x*uSpineShadowParameter.x - x*x );\n"
90 " vec2 spineNormal = normalize(vec2(uSpineShadowParameter.y*x/uSpineShadowParameter.x, y));\n"
91 " gl_FragColor.rgb *= spineNormal.y; \n"
97 shader = ShaderEffect::New( vertexSource,fragmentSource );
98 PageTurnBookSpineEffect handle( shader );
99 handle.SetUniform( IS_BACK_IMAGE_VISIBLE_PROPERTY_NAME, -1.f );
100 handle.SetUniform( SHADOW_WIDTH_PROPERTY_NAME, DEFAULT_SHADOW_WIDTH );
101 handle.SetUniform( SPINE_SHADOW_PARAMETER_PROPERTY_NAME, DEFAULT_SPINE_SHADOW_PARAMETER );
102 float defaultPageWidth = Dali::Stage::GetCurrent().GetSize().x;
103 handle.SetUniform( PAGE_WIDTH_PROPERTY_NAME, defaultPageWidth/(1.f-DEFAULT_SHADOW_WIDTH) );
107 void PageTurnBookSpineEffect::SetIsBackImageVisible( bool isBackVisible )
109 float direction = isBackVisible ? 1.0f : -1.0f;
110 SetUniform( IS_BACK_IMAGE_VISIBLE_PROPERTY_NAME, direction );
113 void PageTurnBookSpineEffect::SetPageWidth( float pageWidth )
115 SetUniform( PAGE_WIDTH_PROPERTY_NAME, pageWidth );
118 void PageTurnBookSpineEffect::SetShadowWidth( float shadowWidth )
120 SetUniform( SHADOW_WIDTH_PROPERTY_NAME, shadowWidth );
123 void PageTurnBookSpineEffect::SetSpineShadowParameter( const Vector2& spineShadowParameter )
125 SetUniform( SPINE_SHADOW_PARAMETER_PROPERTY_NAME, spineShadowParameter);
128 } // namespace Toolkit