dali-toolkit/public-api/shader-effects/nine-patch-mask-effect.cpp

   1 //
   2 // Copyright (c) 2014 Samsung Electronics Co., Ltd.
   3 //
   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
   7 //
   8 //     http://floralicense.org/license/
   9 //
  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.
  15 //
  16
  17 // CLASS HEADER
  18 #include <dali-toolkit/public-api/shader-effects/nine-patch-mask-effect.h>
  19
  20 namespace Dali
  21 {
  22
  23 namespace Toolkit
  24 {
  25
  26 namespace NinePatchMaskEffect
  27 {
  28
  29 struct NinePatchMaskEffectSizeConstraint
  30 {
  31   Vector2 operator()( const Vector2& current, const PropertyInput& property )
  32   {
  33     const Vector3& actorSize = property.GetVector3();
  34     return Vector2( actorSize.x, actorSize.y );
  35   }
  36 };
  37
  38 static void DoApply( ImageActor actor, const std::string& maskImage, const Vector2& maskSize, Vector4 maskBorder )
  39 {
  40   const char* ALPHA_MASK_VERTEX_SHADER_SOURCE =
  41   "uniform vec2 uImageSize;                                                       \n"
  42   "uniform vec2 uMaskSize;                                                        \n"
  43   "varying vec2 vMaskTexCoord;                                                    \n"
  44   "                                                                               \n"
  45   "void main()                                                                    \n"
  46   "{                                                                              \n"
  47   "  gl_Position = uMvpMatrix * vec4(aPosition, 1.0);                             \n"
  48   "                                                                               \n"
  49   "  // Ignore mask UVs for image                                                 \n"
  50   "                                                                               \n"
  51   "  highp vec2 halfImageSize = uImageSize * 0.5;                                 \n"
  52   "  vTexCoord = (aPosition.xy + halfImageSize) / uImageSize;                     \n"
  53   "                                                                               \n"
  54   "  // UVs were calculated for image size, so convert for mask size              \n"
  55   "                                                                               \n"
  56   "  highp vec2 halfMaskSize  = uMaskSize * 0.5;                                  \n"
  57   "  highp vec2 halfSizeDelta = halfImageSize - halfMaskSize;                     \n"
  58   "                                                                               \n"
  59   "  highp vec2 maskPosition = aPosition.xy;                                      \n"
  60   "  maskPosition.x -= halfSizeDelta.x * sign(aPosition.x);                       \n"
  61   "  maskPosition.y -= halfSizeDelta.y * sign(aPosition.y);                       \n"
  62   "                                                                               \n"
  63   "  vMaskTexCoord = (maskPosition + halfMaskSize) / uMaskSize;                   \n"
  64   "}                                                                              \n";
  65
  66   const char* ALPHA_MASK_FRAGMENT_SHADER_SOURCE =
  67   "varying vec2 vMaskTexCoord;                                                    \n"
  68   "                                                                               \n"
  69   "void main()                                                                    \n"
  70   "{                                                                              \n"
  71   "  highp vec4 mask = texture2D(sEffect, vMaskTexCoord);                         \n"
  72   "  gl_FragColor = texture2D(sTexture, vTexCoord) * uColor * vec4(1,1,1,mask.a); \n"
  73   "}                                                                              \n";
  74
  75   ShaderEffect maskEffect = ShaderEffect::New( ALPHA_MASK_VERTEX_SHADER_SOURCE,
  76                                                ALPHA_MASK_FRAGMENT_SHADER_SOURCE,
  77                                                GeometryType( GEOMETRY_TYPE_IMAGE ),
  78                                                ShaderEffect::GeometryHints( ShaderEffect::HINT_BLENDING ) );
  79
  80   maskEffect.SetEffectImage( Image::New( maskImage ) );
  81
  82   maskEffect.SetUniform( "uImageSize", Vector2(0,0) /*Constrained to actor size*/ );
  83   maskEffect.ApplyConstraint( Constraint::New<Vector2>( maskEffect.GetPropertyIndex("uImageSize"),
  84                                                         Source(actor, Actor::SIZE),
  85                                                         NinePatchMaskEffectSizeConstraint() ) );
  86
  87   maskEffect.SetUniform( "uMaskSize", maskSize );
  88
  89   // Actor must provide nine-patch style geometry for this effect to work
  90   actor.SetStyle( ImageActor::STYLE_NINE_PATCH );
  91   actor.SetNinePatchBorder( maskBorder );
  92
  93   actor.SetShaderEffect( maskEffect );
  94 }
  95
  96 void Apply( ImageActor actor, const std::string& maskImage )
  97 {
  98   Vector2 maskSize = Image::GetImageSize( maskImage );
  99
 100   const float leftRight = (maskSize.width  - 1.0f) * 0.5f;
 101   const float topBottom = (maskSize.height - 1.0f) * 0.5f;
 102
 103   DoApply( actor, maskImage, maskSize, Vector4( leftRight, topBottom, leftRight, topBottom ) );
 104 }
 105
 106 void Apply( ImageActor actor, const std::string& maskImage, const Vector4& maskBorder )
 107 {
 108   Vector2 maskSize = Image::GetImageSize( maskImage );
 109
 110   DoApply( actor, maskImage, maskSize, maskBorder );
 111 }
 112
 113 } // namespace NinePatchMaskEffect
 114
 115 } // namespace Toolkit
 116
 117 } // namespace Dali