1 #ifndef __DALI_TOOLKIT_IMAGE_REGION_EFFECT_H__
2 #define __DALI_TOOLKIT_IMAGE_REGION_EFFECT_H__
5 * Copyright (c) 2015 Samsung Electronics Co., Ltd.
7 * Licensed under the Apache License, Version 2.0 (the "License");
8 * you may not use this file except in compliance with the License.
9 * You may obtain a copy of the License at
11 * http://www.apache.org/licenses/LICENSE-2.0
13 * Unless required by applicable law or agreed to in writing, software
14 * distributed under the License is distributed on an "AS IS" BASIS,
15 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16 * See the License for the specific language governing permissions and
17 * limitations under the License.
22 #include <dali/public-api/object/property-map.h>
31 * @brief Creates a new ImageRegionEffect
33 * ImageRegionEffect is a custom shader effect to show only a region of an Image actor.
35 * Animatable/Constrainable uniforms:
36 * "uTopLeft" - The top-left corner of the image region. The coordinates are in percentage,
37 * (0,0) being the top-left and (1,1) the bottom right of the original image
38 * "uBottomRight" - The bottom-right corner of the image region. The coordinates are in percentage,
39 * (0,0) being the top-left and (1,1) the bottom right of the original image
41 * @return A handle to a newly allocated ShaderEffect
43 inline Property::Map CreateImageRegionEffect()
45 std::string vertexShader(
46 "attribute mediump vec2 aPosition;\n"
48 "uniform mediump mat4 uMvpMatrix;\n"
49 "uniform vec3 uSize;\n"
50 "uniform vec4 uTextureRect;"
52 "varying vec2 vTexCoord;\n"
54 "uniform mediump vec2 uTopLeft;\n"
55 "uniform mediump vec2 uBottomRight;\n"
58 " mediump vec4 position = vec4(aPosition, 0.0, 1.0);\n"
59 " position.xyz *= uSize;\n"
60 " gl_Position = uMvpMatrix * position;\n"
61 // The line below is doing the same as the following commented lines:
62 //" vec2 imageSize = sTextureRect.zw - sTextureRect.xy;\n"
63 //" vec2 topLeft = sTextureRect.xy + uTopLeft * imageSize;\n"
64 //" vec2 bottomRight = sTextureRect.xy + uBottomRight * imageSize;\n"
65 //" vec2 texCoord = (aTexCoord - sTextureRect.xy) / imageSize;\n"
66 //" vTexCoord = topLeft + texCoord * ( bottomRight - topLeft );\n"
68 " vec2 texCoord = aPosition + vec2(0.5);\n"
69 " vTexCoord = uTextureRect.xy + uTopLeft * ( uTextureRect.zw - uTextureRect.xy ) + ( texCoord - uTextureRect.xy ) * ( uBottomRight - uTopLeft );\n"
75 Property::Map customShader;
76 customShader[ "vertexShader" ] = vertexShader;
78 map[ "shader" ] = customShader;
82 } // namespace Toolkit
86 #endif // __DALI_TOOLKIT_IMAGE_REGION_EFFECT_H__