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

   1 /*
   2  * Copyright (c) 2015 Samsung Electronics Co., Ltd.
   3  *
   4  * Licensed under the Apache License, Version 2.0 (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://www.apache.org/licenses/LICENSE-2.0
   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
  18 // CLASS HEADER
  19 #include <dali-toolkit/devel-api/shader-effects/nine-patch-mask-effect.h>
  20
  21 // EXTERNAL INCLUDES
  22 #include <dali/public-api/animation/constraint.h>
  23 #include <dali/public-api/object/property-input.h>
  24 #include <dali/public-api/shader-effects/shader-effect.h>
  25 #include <dali/public-api/images/resource-image.h>
  26
  27 namespace Dali
  28 {
  29
  30 namespace Toolkit
  31 {
  32
  33 namespace NinePatchMaskEffect
  34 {
  35
  36 namespace
  37 {
  38
  39 void NinePatchMaskEffectSizeConstraint( Vector2& current, const PropertyInputContainer& inputs )
  40 {
  41   const Vector3& actorSize = inputs[0]->GetVector3();
  42   current.x = actorSize.x;
  43   current.y = actorSize.y;
  44 }
  45
  46 } // unnamed namespace
  47
  48 static void DoApply( ImageActor actor, const std::string& maskImage, const Vector2& maskSize, Vector4 maskBorder )
  49 {
  50   const char* ALPHA_MASK_VERTEX_SHADER_SOURCE =
  51   "precision mediump float;\n"
  52   "uniform vec2 uImageSize;                                                       \n"
  53   "uniform vec2 uMaskSize;                                                        \n"
  54   "varying vec2 vMaskTexCoord;                                                    \n"
  55   "                                                                               \n"
  56   "void main()                                                                    \n"
  57   "{                                                                              \n"
  58   "  gl_Position = uMvpMatrix * vec4(aPosition, 1.0);                             \n"
  59   "                                                                               \n"
  60   "  // Ignore mask UVs for image                                                 \n"
  61   "                                                                               \n"
  62   "  highp vec2 halfImageSize = uImageSize * 0.5;                                 \n"
  63   "  vTexCoord = (aPosition.xy + halfImageSize) / uImageSize;                     \n"
  64   "                                                                               \n"
  65   "  // UVs were calculated for image size, so convert for mask size              \n"
  66   "                                                                               \n"
  67   "  highp vec2 halfMaskSize  = uMaskSize * 0.5;                                  \n"
  68   "  highp vec2 halfSizeDelta = halfImageSize - halfMaskSize;                     \n"
  69   "                                                                               \n"
  70   "  highp vec2 maskPosition = aPosition.xy;                                      \n"
  71   "  maskPosition.x -= halfSizeDelta.x * sign(aPosition.x);                       \n"
  72   "  maskPosition.y -= halfSizeDelta.y * sign(aPosition.y);                       \n"
  73   "                                                                               \n"
  74   "  vMaskTexCoord = (maskPosition + halfMaskSize) / uMaskSize;                   \n"
  75   "}                                                                              \n";
  76
  77   const char* ALPHA_MASK_FRAGMENT_SHADER_SOURCE =
  78   "varying mediump vec2 vMaskTexCoord;                                            \n"
  79   "                                                                               \n"
  80   "void main()                                                                    \n"
  81   "{                                                                              \n"
  82   "  highp vec4 mask = texture2D(sEffect, vMaskTexCoord);                         \n"
  83   "  gl_FragColor = texture2D(sTexture, vTexCoord) * uColor * vec4(1,1,1,mask.a); \n"
  84   "}                                                                              \n";
  85
  86   ShaderEffect maskEffect = ShaderEffect::New(
  87     ALPHA_MASK_VERTEX_SHADER_SOURCE,
  88     ALPHA_MASK_FRAGMENT_SHADER_SOURCE,
  89     GeometryType( GEOMETRY_TYPE_IMAGE ),
  90     ShaderEffect::GeometryHints( ShaderEffect::HINT_BLENDING ) );
  91
  92   maskEffect.SetEffectImage( ResourceImage::New( maskImage ) );
  93
  94   maskEffect.SetUniform( "uImageSize", Vector2(0,0) /*Constrained to actor size*/ );
  95
  96   Constraint constraint = Constraint::New<Vector2>( maskEffect, maskEffect.GetPropertyIndex("uImageSize"), NinePatchMaskEffectSizeConstraint );
  97   constraint.AddSource( Source(actor, Actor::Property::SIZE) );
  98   constraint.Apply();
  99
 100   maskEffect.SetUniform( "uMaskSize", maskSize );
 101
 102   // Actor must provide nine-patch style geometry for this effect to work
 103   actor.SetStyle( ImageActor::STYLE_NINE_PATCH );
 104   actor.SetNinePatchBorder( maskBorder );
 105
 106   actor.SetShaderEffect( maskEffect );
 107 }
 108
 109 void Apply( ImageActor actor, const std::string& maskImage )
 110 {
 111   const Uint16Pair maskSize = ResourceImage::GetImageSize( maskImage );
 112
 113   const float leftRight = (maskSize.GetWidth()  - 1.0f) * 0.5f;
 114   const float topBottom = (maskSize.GetHeight() - 1.0f) * 0.5f;
 115
 116   DoApply( actor, maskImage, Vector2( maskSize.GetWidth(), maskSize.GetHeight() ), Vector4( leftRight, topBottom, leftRight, topBottom ) );
 117 }
 118
 119 void Apply( ImageActor actor, const std::string& maskImage, const Vector4& maskBorder )
 120 {
 121   const Uint16Pair maskSize = ResourceImage::GetImageSize( maskImage );
 122
 123   DoApply( actor, maskImage, Vector2( maskSize.GetWidth(), maskSize.GetHeight() ), maskBorder );
 124 }
 125
 126 } // namespace NinePatchMaskEffect
 127
 128 } // namespace Toolkit
 129
 130 } // namespace Dali