{
/**
+ * @brief Set the properties for the motion stretch
+ */
+inline void SetMotionStretchProperties( Actor& actor )
+{
+ actor.RegisterProperty( "uGeometryStretchFactor", 0.5f );
+ actor.RegisterProperty( "uSpeedScalingFactor", 0.5f );
+ actor.RegisterProperty( "uObjectFadeStart", Vector2( 0.25f, 0.25f ) );
+ actor.RegisterProperty( "uObjectFadeEnd", Vector2( 0.5f, 0.5f ) );
+ actor.RegisterProperty( "uAlphaScale", 0.75f );
+ Property::Index uModelProperty = actor.RegisterProperty( "uModelLastFrame", Matrix::IDENTITY );
+
+ Constraint constraint = Constraint::New<Matrix>( actor, uModelProperty, EqualToConstraint() );
+ constraint.AddSource( Source( actor , Actor::Property::WORLD_MATRIX ) );
+ constraint.Apply();
+}
+
+/**
* @brief Creates a new MotionStretchEffect
*
- * Motion stretch shader works on a per object basis. Objects will stretch in the direction of motion when they move, or if the camera moves. Can be applied
- * to ImageActor or TextActor only.
- *
- * Usage example:-
- *
- * // Create shader used for doing motion stretch\n
- * ShaderEffect MotionStretchEffect = CreateMotionStretchEffect();
- *
- * // set actor shader to the stretch one\n
- * Actor actor = Actor::New( ... );\n
- * actor.SetShaderEffect( MotionStretchEffect );
- *
- * // Constrain "uModelLastFrame" to be the same as the actor's world matrix\n
- * Dali::Property::Index uModelProperty = MotionBlurEffect.GetPropertyIndex( "uModelLastFrame" );
- * Constraint constraint = Constraint::New<Matrix>( MotionBlurEffect, uModelProperty, EqualToConstraint() );\n
- * constraint.AddSource( Source( actor , Actor::Property::WORLD_MATRIX ) );\n
- * constraint.Apply();\n
+ * Motion stretch shader works on a per object basis. Objects will stretch in the direction of motion when they move, or if the camera moves.
*
* Animatable/Constrainable uniforms:
* "uGeometryStretchFactor" - This scales the amount the geometry stretches along the motion velocity vector.
* applied. Default 0.75.
* "uModelLastFrame" - The model to world space transformation matrix of the actor in the previous frame.
*
- * @return A handle to a newly allocated ShaderEffect
+ * @return The newly created Property::Map with the motion stretch effect
*/
-inline ShaderEffect CreateMotionStretchEffect()
+inline Property::Map CreateMotionStretchEffect()
{
- // Dali vertexSource prefix for reference:
- // precision highp float;
- // attribute vec3 aPosition;
- // attribute vec2 aTexCoord;
- // uniform mat4 uMvpMatrix;
- // uniform mat4 uModelView;
- // uniform mat3 uNormalMatrix;
- // uniform mat4 uProjection;
- // uniform vec4 uColor;
- // varying vec2 vTexCoord;
std::string vertexSource;
vertexSource =
"precision mediump float;\n"
+
+ "attribute vec2 aPosition;\n"
+
+ "uniform mat4 uMvpMatrix;\n"
+ "uniform mat4 uModelView;\n"
+ "uniform mat4 uViewMatrix;\n"
+ "uniform mat4 uProjection;\n"
+ "uniform vec3 uSize;\n"
+
"uniform mat4 uModelLastFrame;\n"
- "uniform float uTimeDelta;\n"
+ "float timeDelta = 0.0167;\n"
"uniform float uGeometryStretchFactor;\n"
"uniform float uSpeedScalingFactor;\n"
"varying vec2 vModelSpaceCenterToPos;\n"
"varying vec2 vScreenSpaceVelocityVector;\n"
"varying float vSpeed;\n"
+ "varying vec2 vTexCoord;\n"
"void main()\n"
"{\n"
// get view space position of vertex this frame and last frame
- " vec4 vertex = vec4(aPosition, 1.0);\n"
- " vec4 viewSpaceVertex = uModelView * vertex;\n"
- " vec4 viewSpaceVertexLastFrame = uViewMatrix * uModelLastFrame * vertex;\n"
+ " vec4 vertexPosition = vec4(aPosition, 0.0, 1.0);\n"
+ " vertexPosition.xyz *= uSize;\n"
+
+ " vec4 viewSpaceVertex = uModelView * vertexPosition;\n"
+ " vec4 viewSpaceVertexLastFrame = uViewMatrix * uModelLastFrame * vertexPosition;\n"
// work out vertex's last movement in view space
" vec3 viewSpacePosDelta = viewSpaceVertex.xyz - viewSpaceVertexLastFrame.xyz;\n"
- " float reciprocalTimeDelta = 1.0 / ((uTimeDelta > 0.0) ? uTimeDelta : 0.01);\n"
+ " float reciprocalTimeDelta = 1.0 / timeDelta;\n"
// get clip space position of vertex this frame and last frame
- " vec4 clipSpaceVertex = uMvpMatrix * vertex;\n"
+ " vec4 clipSpaceVertex = uMvpMatrix * vertexPosition;\n"
" vec4 clipSpaceVertexLastFrame = uProjection * viewSpaceVertexLastFrame;\n"
// decide how much this vertex is 'trailing', i.e. at the back of the object relative to its direction of motion. We do this
" float posDeltaLength = length(viewSpacePosDelta);\n"
" if(posDeltaLength > 0.001)\n" // avoid div by 0 if object has barely moved
" {\n"
- " vec4 viewSpaceCenterToPos = uModelView * vec4(aPosition, 0.0);\n"
+ " vec4 viewSpaceCenterToPos = uModelView * vec4(aPosition, 0.0, 0.0);\n"
" float centerToVertexDist = length(viewSpaceCenterToPos);\n"
" if(centerToVertexDist > 0.001)\n" // avoid div by 0 if object has vertex at model space origin
" {\n"
" vSpeed = clamp(vSpeed, 0.0, 1.0);\n"
// provide fragment shader with vector from center of object to pixel (assumes the objects model space origin is at its center and verts have same z)
- " vModelSpaceCenterToPos = aPosition.xy;\n"
+ " vModelSpaceCenterToPos = viewSpaceVertex.xy;\n"
- " vTexCoord = aTexCoord;\n"
+ " vec2 texCoord = aPosition + vec2(0.5);"
+ " vTexCoord = texCoord;\n"
"}\n";
-
- // Dali fragmentSource prefix for reference:
- // precision highp float;
- // uniform sampler2D sTexture;
- // uniform sampler2D sEffect;
- // uniform vec4 uColor;
- // varying vec2 vTexCoord;
std::string fragmentSource;
fragmentSource =
"precision mediump float;\n"
+ "uniform sampler2D sTexture;\n"
+ "uniform vec4 uColor;\n"
+
"uniform vec2 uObjectFadeStart;\n"
"uniform vec2 uObjectFadeEnd;\n"
"uniform float uAlphaScale;\n"
"varying vec2 vModelSpaceCenterToPos;\n"
"varying vec2 vScreenSpaceVelocityVector;\n"
"varying float vSpeed;\n"
+ "varying vec2 vTexCoord;\n"
"void main()\n"
"{\n"
" gl_FragColor *= uColor;\n"
"}";
+ Property::Map map;
+
+ Property::Map customShader;
+ customShader[ "vertex-shader" ] = vertexSource;
+ customShader[ "fragment-shader" ] = fragmentSource;
+
+ customShader[ "subdivide-grid-x" ] = 10;
+ customShader[ "subdivide-grid-y" ] = 10;
+
// NOTE: we must turn on alpha blending for the actor (HINT_BLENDING)
- ShaderEffect shaderEffect = ShaderEffect::New(
- vertexSource, fragmentSource,
- ShaderEffect::GeometryHints( ShaderEffect::HINT_BLENDING | ShaderEffect::HINT_GRID ) );
-
-
- //////////////////////////////////////
- // Register uniform properties
- //
- //
- shaderEffect.SetUniform( "uGeometryStretchFactor", 0.5f );
- shaderEffect.SetUniform( "uSpeedScalingFactor", 0.5f );
- shaderEffect.SetUniform( "uObjectFadeStart", Vector2( 0.25f, 0.25f ) );
- shaderEffect.SetUniform( "uObjectFadeEnd", Vector2( 0.5f, 0.5f ) );
- shaderEffect.SetUniform( "uAlphaScale", 0.75f );
- shaderEffect.SetUniform( "uModelLastFrame", Matrix::IDENTITY );
-
- return shaderEffect;
+ customShader[ "hints" ] = "output-is-transparent";
+
+ map[ "shader" ] = customShader;
+ return map;
}
}