namespace Toolkit
{
/**
- * @brief QuadraticBezier is a custom shader to render quadratic bezier curves and bounded regions.
+ * @brief Creates a new QuadraticBezier shader effect
+ *
+ * QuadraticBezier is a custom shader to render quadratic bezier curves and bounded regions.
*
* Implementation based on the paper "Resolution Independent Curve Rendering using Programmable Graphics Hardware"
* by Charles Loop and Jim Blinn.
* aNormal attribute is used to pass the coefficients of each control point (xy coordinates) as well as the vertex ID (z coordinate).
* A quadratic curve should have as normal for the first control point (0.0,0.0), (0.5,0.0) for the second and (1.0,1.0) for the third.
* Triangles that do not contain curves should have coordinates (0.0,1.0) for each control point in order to be filled properly.
+ *
+ * Animatable/Constrainable uniforms:
+ * "uPoint" - Position coordinates for the points in the curve
+ * "uColor" - The color of the curve or bounded region
+ * "uLineWidth" - The width of the path. Only for not filled curves
+ *
+ * @param[in] pointCount The maximum number of vertices
+ * @param[in] filled Specify whether the the bounded region should be filled or not
+ * @return A handle to a newly allocated ShaderEffect
*/
-
-class DALI_IMPORT_API QuadraticBezier : public ShaderEffect
+inline ShaderEffect CreateQuadraticBezier(unsigned int pointCount, bool filled)
{
-public:
-
- /**
- * @brief Create an uninitialized QuadraticBezier; this can be initialized with QuadraticBezier::New().
- *
- * Calling member functions with an uninitialized Dali::Object is not allowed.
- */
- QuadraticBezier();
-
- /**
- * @brief Destructor
- *
- * This is non-virtual since derived Handle types must not contain data or virtual methods.
- */
- ~QuadraticBezier();
-
- /**
- * @brief Create an initialized QuadraticBezier.
- *
- * @param[in] pointCount The maximum number of vertices
- * @param[in] filled Specify whether the the bounded region should be filled or not
- * @return A handle to a newly allocated Dali resource.
- */
- static QuadraticBezier New(unsigned int pointCount, bool filled );
-
- /**
- * @brief Set position coordinates for a point in the curve
- *
- * @param[in] index The index of the vertex
- * @param[in] position The new position
- */
- void SetPoint( unsigned int index, const Vector3& position );
-
- /**
- * @brief Set the width of the pathThis is only for not filled curves
- *
- * @param[in] width Width of the line in pixels
- */
- void SetLineWidth( float width );
-
- /**
- * @brief Sets the color of the curve
- *
- * @param[in] color The new color
- */
- void SetColor( const Vector4& color );
-
- /**
- * @brief Get the name of a the point property given its index
- *
- * @param[in] index Index of the vertex
- * @return A std::string containing the property name
- */
- std::string GetPointPropertyName( unsigned int index ) const;
-
- /**
- * @brief Get the name of the line width property
- *
- * @return A std::string containing the property name
- */
- std::string GetLineWidthPropertyName( ) const;
-
- /**
- * @brief Get the name of the color property
- *
- * @return A std::string containing the property name
- */
- std::string GetColorPropertyName( ) const;
-
-private: // Not intended for application developers
-
- DALI_INTERNAL QuadraticBezier(ShaderEffect handle);
-
-};
+ std::string vertexShader = DALI_COMPOSE_SHADER
+ (
+ uniform mediump vec3 uPoint[MAX_POINT_COUNT];\n
+ varying highp vec2 vCoefficient;
+ void main()\n
+ {\n
+ int vertexId = int(aNormal.z);\n
+ gl_Position = uMvpMatrix * vec4(uPoint[vertexId], 1.0);\n
+ vCoefficient = aNormal.xy;\n
+ }\n
+ );
+
+ std::string fragmentShader;
+
+ if( filled )
+ {
+ fragmentShader = DALI_COMPOSE_SHADER
+ (
+ varying highp vec2 vCoefficient;\n
+
+ void main()\n
+ {\n
+ highp float C = (vCoefficient.x*vCoefficient.x-vCoefficient.y);\n
+ highp float Cdx = dFdx(C);\n
+ highp float Cdy = dFdy(C);\n
+
+ highp float distance = float(C / sqrt(Cdx*Cdx + Cdy*Cdy));\n
+
+ gl_FragColor = uColor;\n
+ highp float alpha = 0.5 - distance;\n
+ if( alpha < 0.0 )\n
+ discard;\n
+
+ gl_FragColor.w = alpha;\n
+ }\n
+ );
+ }
+ else
+ {
+ fragmentShader = DALI_COMPOSE_SHADER
+ (
+ varying highp vec2 vCoefficient;\n
+ uniform lowp float uLineWidth;\n
+
+ void main()\n
+ {\n
+ highp float C = (vCoefficient.x*vCoefficient.x-vCoefficient.y);\n
+ highp float Cdx = dFdx(C);\n
+ highp float Cdy = dFdy(C);\n
+ highp float distance = abs(float(C / sqrt(Cdx*Cdx + Cdy*Cdy)));\n
+ gl_FragColor = uColor*(uLineWidth-distance);\n
+ }\n
+ );
+ }
+
+ std::ostringstream vertexShaderPrefix;
+ vertexShaderPrefix << "#define MAX_POINT_COUNT "<< pointCount << "\n";
+
+ Dali::ShaderEffect shaderEffect = Dali::ShaderEffect::NewWithPrefix(
+ vertexShaderPrefix.str(),vertexShader,
+ "#extension GL_OES_standard_derivatives:enable\n", fragmentShader,
+ GeometryType(GEOMETRY_TYPE_UNTEXTURED_MESH) );
+
+ //Set default uniform values
+ shaderEffect.SetUniform( "uColor", Vector4(1.0f,1.0f,1.0f,1.0f) );
+ if( !filled )
+ {
+ //Set default line widht to 1 pixel
+ shaderEffect.SetUniform( "uLineWidth", 1.0f );
+ }
+
+ return shaderEffect;
+}
} // namespace Toolkit
projects / platform / core / uifw / dali-toolkit.git / blobdiff