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| 39 | |
| 40 | #include <private/qquickshadereffect_p.h> |
| 41 | #include <private/qsgcontextplugin_p.h> |
| 42 | #include <private/qquickitem_p.h> |
| 43 | #if QT_CONFIG(opengl) |
| 44 | #include <private/qquickopenglshadereffect_p.h> |
| 45 | #endif |
| 46 | #include <private/qquickgenericshadereffect_p.h> |
| 47 | #if QT_CONFIG(opengl) /* || QT_CONFIG(vulkan) || defined(Q_OS_WIN) || defined(Q_OS_DARWIN) */ |
| 48 | #include <private/qsgrhisupport_p.h> |
| 49 | #endif |
| 50 | |
| 51 | QT_BEGIN_NAMESPACE |
| 52 | |
| 53 | /*! |
| 54 | \qmltype ShaderEffect |
| 55 | \instantiates QQuickShaderEffect |
| 56 | \inqmlmodule QtQuick |
| 57 | \inherits Item |
| 58 | \ingroup qtquick-effects |
| 59 | \brief Applies custom shaders to a rectangle. |
| 60 | |
| 61 | The ShaderEffect type applies a custom |
| 62 | \l{vertexShader}{vertex} and \l{fragmentShader}{fragment (pixel)} shader to a |
| 63 | rectangle. It allows you to write effects such as drop shadow, blur, |
| 64 | colorize and page curl directly in QML. |
| 65 | |
| 66 | \note Depending on the Qt Quick scenegraph backend in use, the ShaderEffect |
| 67 | type may not be supported (for example, with the software backend), or may |
| 68 | use a different shading language with rules and expectations different from |
| 69 | OpenGL and GLSL. |
| 70 | |
| 71 | \section1 OpenGL and GLSL |
| 72 | |
| 73 | There are two types of input to the \l vertexShader: |
| 74 | uniform variables and attributes. Some are predefined: |
| 75 | \list |
| 76 | \li uniform mat4 qt_Matrix - combined transformation |
| 77 | matrix, the product of the matrices from the root item to this |
| 78 | ShaderEffect, and an orthogonal projection. |
| 79 | \li uniform float qt_Opacity - combined opacity, the product of the |
| 80 | opacities from the root item to this ShaderEffect. |
| 81 | \li attribute vec4 qt_Vertex - vertex position, the top-left vertex has |
| 82 | position (0, 0), the bottom-right (\l{Item::width}{width}, |
| 83 | \l{Item::height}{height}). |
| 84 | \li attribute vec2 qt_MultiTexCoord0 - texture coordinate, the top-left |
| 85 | coordinate is (0, 0), the bottom-right (1, 1). If \l supportsAtlasTextures |
| 86 | is true, coordinates will be based on position in the atlas instead. |
| 87 | \endlist |
| 88 | |
| 89 | In addition, any property that can be mapped to an OpenGL Shading Language |
| 90 | (GLSL) type is available as a uniform variable. The following list shows |
| 91 | how properties are mapped to GLSL uniform variables: |
| 92 | \list |
| 93 | \li bool, int, qreal -> bool, int, float - If the type in the shader is not |
| 94 | the same as in QML, the value is converted automatically. |
| 95 | \li QColor -> vec4 - When colors are passed to the shader, they are first |
| 96 | premultiplied. Thus Qt.rgba(0.2, 0.6, 1.0, 0.5) becomes |
| 97 | vec4(0.1, 0.3, 0.5, 0.5) in the shader, for example. |
| 98 | \li QRect, QRectF -> vec4 - Qt.rect(x, y, w, h) becomes vec4(x, y, w, h) in |
| 99 | the shader. |
| 100 | \li QPoint, QPointF, QSize, QSizeF -> vec2 |
| 101 | \li QVector3D -> vec3 |
| 102 | \li QVector4D -> vec4 |
| 103 | \li QTransform -> mat3 |
| 104 | \li QMatrix4x4 -> mat4 |
| 105 | \li QQuaternion -> vec4, scalar value is \c w. |
| 106 | \li \l Image -> sampler2D - Origin is in the top-left corner, and the |
| 107 | color values are premultiplied. The texture is provided as is, |
| 108 | excluding the Image item's fillMode. To include fillMode, use a |
| 109 | ShaderEffectSource or Image::layer::enabled. |
| 110 | \li \l ShaderEffectSource -> sampler2D - Origin is in the top-left |
| 111 | corner, and the color values are premultiplied. |
| 112 | \endlist |
| 113 | |
| 114 | The QML scene graph back-end may choose to allocate textures in texture |
| 115 | atlases. If a texture allocated in an atlas is passed to a ShaderEffect, |
| 116 | it is by default copied from the texture atlas into a stand-alone texture |
| 117 | so that the texture coordinates span from 0 to 1, and you get the expected |
| 118 | wrap modes. However, this will increase the memory usage. To avoid the |
| 119 | texture copy, set \l supportsAtlasTextures for simple shaders using |
| 120 | qt_MultiTexCoord0, or for each "uniform sampler2D <name>" declare a |
| 121 | "uniform vec4 qt_SubRect_<name>" which will be assigned the texture's |
| 122 | normalized source rectangle. For stand-alone textures, the source rectangle |
| 123 | is [0, 1]x[0, 1]. For textures in an atlas, the source rectangle corresponds |
| 124 | to the part of the texture atlas where the texture is stored. |
| 125 | The correct way to calculate the texture coordinate for a texture called |
| 126 | "source" within a texture atlas is |
| 127 | "qt_SubRect_source.xy + qt_SubRect_source.zw * qt_MultiTexCoord0". |
| 128 | |
| 129 | The output from the \l fragmentShader should be premultiplied. If |
| 130 | \l blending is enabled, source-over blending is used. However, additive |
| 131 | blending can be achieved by outputting zero in the alpha channel. |
| 132 | |
| 133 | \table 70% |
| 134 | \row |
| 135 | \li \image declarative-shadereffectitem.png |
| 136 | \li \qml |
| 137 | import QtQuick 2.0 |
| 138 | |
| 139 | Rectangle { |
| 140 | width: 200; height: 100 |
| 141 | Row { |
| 142 | Image { id: img; |
| 143 | sourceSize { width: 100; height: 100 } source: "qt-logo.png" } |
| 144 | ShaderEffect { |
| 145 | width: 100; height: 100 |
| 146 | property variant src: img |
| 147 | vertexShader: " |
| 148 | uniform highp mat4 qt_Matrix; |
| 149 | attribute highp vec4 qt_Vertex; |
| 150 | attribute highp vec2 qt_MultiTexCoord0; |
| 151 | varying highp vec2 coord; |
| 152 | void main() { |
| 153 | coord = qt_MultiTexCoord0; |
| 154 | gl_Position = qt_Matrix * qt_Vertex; |
| 155 | }" |
| 156 | fragmentShader: " |
| 157 | varying highp vec2 coord; |
| 158 | uniform sampler2D src; |
| 159 | uniform lowp float qt_Opacity; |
| 160 | void main() { |
| 161 | lowp vec4 tex = texture2D(src, coord); |
| 162 | gl_FragColor = vec4(vec3(dot(tex.rgb, |
| 163 | vec3(0.344, 0.5, 0.156))), |
| 164 | tex.a) * qt_Opacity; |
| 165 | }" |
| 166 | } |
| 167 | } |
| 168 | } |
| 169 | \endqml |
| 170 | \endtable |
| 171 | |
| 172 | \note Scene Graph textures have origin in the top-left corner rather than |
| 173 | bottom-left which is common in OpenGL. |
| 174 | |
| 175 | For information about the GLSL version being used, see \l QtQuick::GraphicsInfo. |
| 176 | |
| 177 | Starting from Qt 5.8 ShaderEffect also supports reading the GLSL source |
| 178 | code from files. Whenever the fragmentShader or vertexShader property value |
| 179 | is a URL with the \c file or \c qrc schema, it is treated as a file |
| 180 | reference and the source code is read from the specified file. |
| 181 | |
| 182 | \section1 Direct3D and HLSL |
| 183 | |
| 184 | Direct3D backends provide ShaderEffect support with HLSL. The Direct3D 12 |
| 185 | backend requires using at least Shader Model 5.0 both for vertex and pixel |
| 186 | shaders. When necessary, GraphicsInfo.shaderType can be used to decide |
| 187 | at runtime what kind of value to assign to \l fragmentShader or |
| 188 | \l vertexShader. |
| 189 | |
| 190 | All concepts described above for OpenGL and GLSL apply to Direct3D and HLSL |
| 191 | as well. There are however a number of notable practical differences, which |
| 192 | are the following: |
| 193 | |
| 194 | Instead of uniforms, HLSL shaders are expected to use a single constant |
| 195 | buffer, assigned to register \c b0. The special names \c qt_Matrix, |
| 196 | \c qt_Opacity, and \c qt_SubRect_<name> function the same way as with GLSL. |
| 197 | All other members of the buffer are expected to map to properties in the |
| 198 | ShaderEffect item. |
| 199 | |
| 200 | \note The buffer layout must be compatible for both shaders. This means |
| 201 | that application-provided shaders must make sure \c qt_Matrix and |
| 202 | \c qt_Opacity are included in the buffer, starting at offset 0, when custom |
| 203 | code is provided for one type of shader only, leading to ShaderEffect |
| 204 | providing the other shader. This is due to ShaderEffect's built-in shader code |
| 205 | declaring a constant buffer containing \c{float4x4 qt_Matrix; float qt_Opacity;}. |
| 206 | |
| 207 | Unlike GLSL's attributes, no names are used for vertex input elements. |
| 208 | Therefore qt_Vertex and qt_MultiTexCoord0 are not relevant. Instead, the |
| 209 | standard Direct3D semantics, \c POSITION and \c TEXCOORD (or \c TEXCOORD0) |
| 210 | are used for identifying the correct input layout. |
| 211 | |
| 212 | Unlike GLSL's samplers, texture and sampler objects are separate in HLSL. |
| 213 | Shaders are expected to expect 2D, non-array, non-multisample textures. |
| 214 | Both the texture and sampler binding points are expected to be sequential |
| 215 | and start from 0 (meaning registers \c{t0, t1, ...}, and \c{s0, s1, ...}, |
| 216 | respectively). Unlike with OpenGL, samplers are not mapped to Qt Quick item |
| 217 | properties and therefore the name of the sampler is not relevant. Instead, |
| 218 | it is the textures that map to properties referencing \l Image or |
| 219 | \l ShaderEffectSource items. |
| 220 | |
| 221 | Unlike OpenGL, backends for modern APIs will typically prefer offline |
| 222 | compilation and shipping pre-compiled bytecode with applications instead of |
| 223 | inlined shader source strings. In this case the string properties for |
| 224 | vertex and fragment shaders are treated as URLs referring to local files or |
| 225 | files shipped via the Qt resource system. |
| 226 | |
| 227 | To check at runtime what is supported, use the |
| 228 | GraphicsInfo.shaderSourceType and GraphicsInfo.shaderCompilationType |
| 229 | properties. Note that these are bitmasks, because some backends may support |
| 230 | multiple approaches. |
| 231 | |
| 232 | In case of Direct3D 12, all combinations are supported. If the vertexShader |
| 233 | and fragmentShader properties form a valid URL with the \c file or \c qrc |
| 234 | schema, the bytecode or HLSL source code is read from the specified file. |
| 235 | The type of the file contents is detected automatically. Otherwise, the |
| 236 | string is treated as HLSL source code and is compiled at runtime, assuming |
| 237 | Shader Model 5.0 and an entry point of \c{"main"}. This allows dynamically |
| 238 | constructing shader strings. However, whenever the shader source code is |
| 239 | static, it is strongly recommended to pre-compile to bytecode using the |
| 240 | \c fxc tool and refer to these files from QML. This will be a lot more |
| 241 | efficient at runtime and allows catching syntax errors in the shaders at |
| 242 | compile time. |
| 243 | |
| 244 | Unlike OpenGL, the Direct3D backend is able to perform runtime shader |
| 245 | compilation on dedicated threads. This is managed transparently to the |
| 246 | applications, and means that ShaderEffect items that contain HLSL source |
| 247 | strings do not block the rendering or other parts of the application until |
| 248 | the bytecode is ready. |
| 249 | |
| 250 | Using files with bytecode is more flexible also when it comes to the entry |
| 251 | point name (it can be anything, not limited to \c main) and the shader |
| 252 | model (it can be something newer than 5.0, for instance 5.1). |
| 253 | |
| 254 | \table 70% |
| 255 | \row |
| 256 | \li \qml |
| 257 | import QtQuick 2.0 |
| 258 | |
| 259 | Rectangle { |
| 260 | width: 200; height: 100 |
| 261 | Row { |
| 262 | Image { id: img; |
| 263 | sourceSize { width: 100; height: 100 } source: "qt-logo.png" } |
| 264 | ShaderEffect { |
| 265 | width: 100; height: 100 |
| 266 | property variant src: img |
| 267 | fragmentShader: "qrc:/effect_ps.cso" |
| 268 | } |
| 269 | } |
| 270 | } |
| 271 | \endqml |
| 272 | \row |
| 273 | \li where \c effect_ps.cso is the compiled bytecode for the following HLSL shader: |
| 274 | \code |
| 275 | cbuffer ConstantBuffer : register(b0) |
| 276 | { |
| 277 | float4x4 qt_Matrix; |
| 278 | float qt_Opacity; |
| 279 | }; |
| 280 | Texture2D src : register(t0); |
| 281 | SamplerState srcSampler : register(s0); |
| 282 | float4 ExamplePixelShader(float4 position : SV_POSITION, float2 coord : TEXCOORD0) : SV_TARGET |
| 283 | { |
| 284 | float4 tex = src.Sample(srcSampler, coord); |
| 285 | float3 col = dot(tex.rgb, float3(0.344, 0.5, 0.156)); |
| 286 | return float4(col, tex.a) * qt_Opacity; |
| 287 | } |
| 288 | \endcode |
| 289 | \endtable |
| 290 | |
| 291 | The above is equivalent to the OpenGL example presented earlier. The vertex |
| 292 | shader is provided implicitly by ShaderEffect. Note that the output of the |
| 293 | pixel shader is using premultiplied alpha and that \c qt_Matrix is present |
| 294 | in the constant buffer at offset 0, even though the pixel shader does not |
| 295 | use the value. |
| 296 | |
| 297 | If desired, the HLSL source code can be placed directly into the QML |
| 298 | source, similarly to how its done with GLSL. The only difference in this |
| 299 | case is the entry point name, which must be \c main when using inline |
| 300 | source strings. |
| 301 | |
| 302 | Alternatively, we could also have referred to a file containing the source |
| 303 | of the effect instead of the compiled bytecode version. |
| 304 | |
| 305 | Some effects will want to provide a vertex shader as well. Below is a |
| 306 | similar effect with both the vertex and fragment shader provided by the |
| 307 | application. This time the colorization factor is provided by the QML item |
| 308 | instead of hardcoding it in the shader. This can allow, among others, |
| 309 | animating the value using QML's and Qt Quick's standard facilities. |
| 310 | |
| 311 | \table 70% |
| 312 | \row |
| 313 | \li \qml |
| 314 | import QtQuick 2.0 |
| 315 | |
| 316 | Rectangle { |
| 317 | width: 200; height: 100 |
| 318 | Row { |
| 319 | Image { id: img; |
| 320 | sourceSize { width: 100; height: 100 } source: "qt-logo.png" } |
| 321 | ShaderEffect { |
| 322 | width: 100; height: 100 |
| 323 | property variant src: img |
| 324 | property variant color: Qt.vector3d(0.344, 0.5, 0.156) |
| 325 | vertexShader: "qrc:/effect_vs.cso" |
| 326 | fragmentShader: "qrc:/effect_ps.cso" |
| 327 | } |
| 328 | } |
| 329 | } |
| 330 | \endqml |
| 331 | \row |
| 332 | \li where \c effect_vs.cso and \c effect_ps.cso are the compiled bytecode |
| 333 | for \c ExampleVertexShader and \c ExamplePixelShader. The source code is |
| 334 | presented as one snippet here, the shaders can however be placed in |
| 335 | separate source files as well. |
| 336 | \code |
| 337 | cbuffer ConstantBuffer : register(b0) |
| 338 | { |
| 339 | float4x4 qt_Matrix; |
| 340 | float qt_Opacity; |
| 341 | float3 color; |
| 342 | }; |
| 343 | Texture2D src : register(t0); |
| 344 | SamplerState srcSampler : register(s0); |
| 345 | struct PSInput |
| 346 | { |
| 347 | float4 position : SV_POSITION; |
| 348 | float2 coord : TEXCOORD0; |
| 349 | }; |
| 350 | PSInput ExampleVertexShader(float4 position : POSITION, float2 coord : TEXCOORD0) |
| 351 | { |
| 352 | PSInput result; |
| 353 | result.position = mul(qt_Matrix, position); |
| 354 | result.coord = coord; |
| 355 | return result; |
| 356 | } |
| 357 | float4 ExamplePixelShader(PSInput input) : SV_TARGET |
| 358 | { |
| 359 | float4 tex = src.Sample(srcSampler, coord); |
| 360 | float3 col = dot(tex.rgb, color); |
| 361 | return float4(col, tex.a) * qt_Opacity; |
| 362 | } |
| 363 | \endcode |
| 364 | \endtable |
| 365 | |
| 366 | \note With OpenGL the \c y coordinate runs from bottom to top whereas with |
| 367 | Direct 3D it goes top to bottom. For shader effect sources Qt Quick hides |
| 368 | the difference by treating QtQuick::ShaderEffectSource::textureMirroring as |
| 369 | appropriate, meaning texture coordinates in HLSL version of the shaders |
| 370 | will not need any adjustments compared to the equivalent GLSL code. |
| 371 | |
| 372 | \section1 Cross-platform, Cross-API ShaderEffect Items |
| 373 | |
| 374 | Some applications will want to be functional with multiple accelerated |
| 375 | graphics backends. This has consequences for ShaderEffect items because the |
| 376 | supported shading languages may vary from backend to backend. |
| 377 | |
| 378 | There are two approaches to handle this: either write conditional property |
| 379 | values based on GraphicsInfo.shaderType, or use file selectors. In practice |
| 380 | the latter is strongly recommended as it leads to more concise and cleaner |
| 381 | application code. The only case it is not suitable is when the source |
| 382 | strings are constructed dynamically. |
| 383 | |
| 384 | \table 70% |
| 385 | \row |
| 386 | \li \qml |
| 387 | import QtQuick 2.8 // for GraphicsInfo |
| 388 | |
| 389 | Rectangle { |
| 390 | width: 200; height: 100 |
| 391 | Row { |
| 392 | Image { id: img; |
| 393 | sourceSize { width: 100; height: 100 } source: "qt-logo.png" } |
| 394 | ShaderEffect { |
| 395 | width: 100; height: 100 |
| 396 | property variant src: img |
| 397 | property variant color: Qt.vector3d(0.344, 0.5, 0.156) |
| 398 | fragmentShader: GraphicsInfo.shaderType === GraphicsInfo.GLSL ? |
| 399 | "varying highp vec2 coord; |
| 400 | uniform sampler2D src; |
| 401 | uniform lowp float qt_Opacity; |
| 402 | void main() { |
| 403 | lowp vec4 tex = texture2D(src, coord); |
| 404 | gl_FragColor = vec4(vec3(dot(tex.rgb, |
| 405 | vec3(0.344, 0.5, 0.156))), |
| 406 | tex.a) * qt_Opacity;" |
| 407 | : GraphicsInfo.shaderType === GraphicsInfo.HLSL ? |
| 408 | "cbuffer ConstantBuffer : register(b0) |
| 409 | { |
| 410 | float4x4 qt_Matrix; |
| 411 | float qt_Opacity; |
| 412 | }; |
| 413 | Texture2D src : register(t0); |
| 414 | SamplerState srcSampler : register(s0); |
| 415 | float4 ExamplePixelShader(float4 position : SV_POSITION, float2 coord : TEXCOORD0) : SV_TARGET |
| 416 | { |
| 417 | float4 tex = src.Sample(srcSampler, coord); |
| 418 | float3 col = dot(tex.rgb, float3(0.344, 0.5, 0.156)); |
| 419 | return float4(col, tex.a) * qt_Opacity; |
| 420 | }" |
| 421 | : "" |
| 422 | } |
| 423 | } |
| 424 | } |
| 425 | \endqml |
| 426 | \row |
| 427 | |
| 428 | \li This is the first approach based on GraphicsInfo. Note that the value |
| 429 | reported by GraphicsInfo is not up-to-date until the ShaderEffect item gets |
| 430 | associated with a QQuickWindow. Before that, the reported value is |
| 431 | GraphicsInfo.UnknownShadingLanguage. The alternative is to place the GLSL |
| 432 | source code and the compiled D3D bytecode into the files |
| 433 | \c{shaders/effect.frag} and \c{shaders/+hlsl/effect.frag}, include them in |
| 434 | the Qt resource system, and let the ShaderEffect's internal QFileSelector |
| 435 | do its job. The selector-less version is the GLSL source, while the \c hlsl |
| 436 | selector is used when running on the D3D12 backend. The file under |
| 437 | \c{+hlsl} can then contain either HLSL source code or compiled bytecode |
| 438 | from the \c fxc tool. Additionally, when using a version 3.2 or newer core |
| 439 | profile context with OpenGL, GLSL sources with a core profile compatible |
| 440 | syntax can be placed under \c{+glslcore}. |
| 441 | \qml |
| 442 | import QtQuick 2.8 // for GraphicsInfo |
| 443 | |
| 444 | Rectangle { |
| 445 | width: 200; height: 100 |
| 446 | Row { |
| 447 | Image { id: img; |
| 448 | sourceSize { width: 100; height: 100 } source: "qt-logo.png" } |
| 449 | ShaderEffect { |
| 450 | width: 100; height: 100 |
| 451 | property variant src: img |
| 452 | property variant color: Qt.vector3d(0.344, 0.5, 0.156) |
| 453 | fragmentShader: "qrc:shaders/effect.frag" // selects the correct variant automatically |
| 454 | } |
| 455 | } |
| 456 | } |
| 457 | \endqml |
| 458 | \endtable |
| 459 | |
| 460 | \section1 ShaderEffect and Item Layers |
| 461 | |
| 462 | The ShaderEffect type can be combined with \l {Item Layers} {layered items}. |
| 463 | |
| 464 | \table |
| 465 | \row |
| 466 | \li \b {Layer with effect disabled} \inlineimage qml-shadereffect-nolayereffect.png |
| 467 | \li \b {Layer with effect enabled} \inlineimage qml-shadereffect-layereffect.png |
| 468 | \row |
| 469 | \li \snippet qml/layerwitheffect.qml 1 |
| 470 | \endtable |
| 471 | |
| 472 | It is also possible to combine multiple layered items: |
| 473 | |
| 474 | \table |
| 475 | \row |
| 476 | \li \inlineimage qml-shadereffect-opacitymask.png |
| 477 | \row |
| 478 | \li \snippet qml/opacitymask.qml 1 |
| 479 | \endtable |
| 480 | |
| 481 | \section1 Other Notes |
| 482 | |
| 483 | By default, the ShaderEffect consists of four vertices, one for each |
| 484 | corner. For non-linear vertex transformations, like page curl, you can |
| 485 | specify a fine grid of vertices by specifying a \l mesh resolution. |
| 486 | |
| 487 | The \l {Qt Graphical Effects} module contains several ready-made effects |
| 488 | for using with Qt Quick applications. |
| 489 | |
| 490 | \sa {Item Layers} |
| 491 | */ |
| 492 | |
| 493 | class QQuickShaderEffectPrivate : public QQuickItemPrivate |
| 494 | { |
| 495 | Q_DECLARE_PUBLIC(QQuickShaderEffect) |
| 496 | |
| 497 | public: |
| 498 | void updatePolish() override; |
| 499 | }; |
| 500 | |
| 501 | QSGContextFactoryInterface::Flags qsg_backend_flags(); |
| 502 | |
| 503 | QQuickShaderEffect::QQuickShaderEffect(QQuickItem *parent) |
| 504 | : QQuickItem(*new QQuickShaderEffectPrivate, parent), |
| 505 | #if QT_CONFIG(opengl) |
| 506 | m_glImpl(nullptr), |
| 507 | #endif |
| 508 | m_impl(nullptr) |
| 509 | { |
| 510 | setFlag(flag: QQuickItem::ItemHasContents); |
| 511 | |
| 512 | #if QT_CONFIG(opengl) /* || QT_CONFIG(vulkan) || defined(Q_OS_WIN) || defined(Q_OS_DARWIN) */ |
| 513 | if (QSGRhiSupport::instance()->isRhiEnabled()) { |
| 514 | m_impl = new QQuickGenericShaderEffect(this, this); |
| 515 | } else |
| 516 | #endif |
| 517 | { |
| 518 | #if QT_CONFIG(opengl) |
| 519 | if (!qsg_backend_flags().testFlag(flag: QSGContextFactoryInterface::SupportsShaderEffectNode)) |
| 520 | m_glImpl = new QQuickOpenGLShaderEffect(this, this); |
| 521 | |
| 522 | if (!m_glImpl) |
| 523 | #endif |
| 524 | m_impl = new QQuickGenericShaderEffect(this, this); |
| 525 | } |
| 526 | } |
| 527 | |
| 528 | QQuickShaderEffect::~QQuickShaderEffect() |
| 529 | { |
| 530 | // Delete the implementations now, while they still have have |
| 531 | // valid references back to us. |
| 532 | #if QT_CONFIG(opengl) |
| 533 | auto *glImpl = m_glImpl; |
| 534 | m_glImpl = nullptr; |
| 535 | delete glImpl; |
| 536 | #endif |
| 537 | auto *impl = m_impl; |
| 538 | m_impl = nullptr; |
| 539 | delete impl; |
| 540 | } |
| 541 | |
| 542 | /*! |
| 543 | \qmlproperty string QtQuick::ShaderEffect::fragmentShader |
| 544 | |
| 545 | This property holds the fragment (pixel) shader's source code or a |
| 546 | reference to the pre-compiled bytecode. Some APIs, like OpenGL, always |
| 547 | support runtime compilation and therefore the traditional Qt Quick way of |
| 548 | inlining shader source strings is functional. Qt Quick backends for other |
| 549 | APIs may however limit support to pre-compiled bytecode like SPIR-V or D3D |
| 550 | shader bytecode. There the string is simply a filename, which may be a file |
| 551 | in the filesystem or bundled with the executable via Qt's resource system. |
| 552 | |
| 553 | With GLSL the default shader expects the texture coordinate to be passed |
| 554 | from the vertex shader as \c{varying highp vec2 qt_TexCoord0}, and it |
| 555 | samples from a sampler2D named \c source. With HLSL the texture is named |
| 556 | \c source, while the vertex shader is expected to provide |
| 557 | \c{float2 coord : TEXCOORD0} in its output in addition to |
| 558 | \c{float4 position : SV_POSITION} (names can differ since linking is done |
| 559 | based on the semantics). |
| 560 | |
| 561 | \sa vertexShader, GraphicsInfo |
| 562 | */ |
| 563 | |
| 564 | QByteArray QQuickShaderEffect::fragmentShader() const |
| 565 | { |
| 566 | #if QT_CONFIG(opengl) |
| 567 | if (m_glImpl) |
| 568 | return m_glImpl->fragmentShader(); |
| 569 | #endif |
| 570 | return m_impl->fragmentShader(); |
| 571 | } |
| 572 | |
| 573 | void QQuickShaderEffect::setFragmentShader(const QByteArray &code) |
| 574 | { |
| 575 | #if QT_CONFIG(opengl) |
| 576 | if (m_glImpl) { |
| 577 | m_glImpl->setFragmentShader(code); |
| 578 | return; |
| 579 | } |
| 580 | #endif |
| 581 | m_impl->setFragmentShader(code); |
| 582 | } |
| 583 | |
| 584 | /*! |
| 585 | \qmlproperty string QtQuick::ShaderEffect::vertexShader |
| 586 | |
| 587 | This property holds the vertex shader's source code or a reference to the |
| 588 | pre-compiled bytecode. Some APIs, like OpenGL, always support runtime |
| 589 | compilation and therefore the traditional Qt Quick way of inlining shader |
| 590 | source strings is functional. Qt Quick backends for other APIs may however |
| 591 | limit support to pre-compiled bytecode like SPIR-V or D3D shader bytecode. |
| 592 | There the string is simply a filename, which may be a file in the |
| 593 | filesystem or bundled with the executable via Qt's resource system. |
| 594 | |
| 595 | With GLSL the default shader passes the texture coordinate along to the |
| 596 | fragment shader as \c{varying highp vec2 qt_TexCoord0}. With HLSL it is |
| 597 | enough to use the standard \c TEXCOORD0 semantic, for example |
| 598 | \c{float2 coord : TEXCOORD0}. |
| 599 | |
| 600 | \sa fragmentShader, GraphicsInfo |
| 601 | */ |
| 602 | |
| 603 | QByteArray QQuickShaderEffect::vertexShader() const |
| 604 | { |
| 605 | #if QT_CONFIG(opengl) |
| 606 | if (m_glImpl) |
| 607 | return m_glImpl->vertexShader(); |
| 608 | #endif |
| 609 | return m_impl->vertexShader(); |
| 610 | } |
| 611 | |
| 612 | void QQuickShaderEffect::setVertexShader(const QByteArray &code) |
| 613 | { |
| 614 | #if QT_CONFIG(opengl) |
| 615 | if (m_glImpl) { |
| 616 | m_glImpl->setVertexShader(code); |
| 617 | return; |
| 618 | } |
| 619 | #endif |
| 620 | m_impl->setVertexShader(code); |
| 621 | } |
| 622 | |
| 623 | /*! |
| 624 | \qmlproperty bool QtQuick::ShaderEffect::blending |
| 625 | |
| 626 | If this property is true, the output from the \l fragmentShader is blended |
| 627 | with the background using source-over blend mode. If false, the background |
| 628 | is disregarded. Blending decreases the performance, so you should set this |
| 629 | property to false when blending is not needed. The default value is true. |
| 630 | */ |
| 631 | |
| 632 | bool QQuickShaderEffect::blending() const |
| 633 | { |
| 634 | #if QT_CONFIG(opengl) |
| 635 | if (m_glImpl) |
| 636 | return m_glImpl->blending(); |
| 637 | #endif |
| 638 | return m_impl->blending(); |
| 639 | } |
| 640 | |
| 641 | void QQuickShaderEffect::setBlending(bool enable) |
| 642 | { |
| 643 | #if QT_CONFIG(opengl) |
| 644 | if (m_glImpl) { |
| 645 | m_glImpl->setBlending(enable); |
| 646 | return; |
| 647 | } |
| 648 | #endif |
| 649 | m_impl->setBlending(enable); |
| 650 | } |
| 651 | |
| 652 | /*! |
| 653 | \qmlproperty variant QtQuick::ShaderEffect::mesh |
| 654 | |
| 655 | This property defines the mesh used to draw the ShaderEffect. It can hold |
| 656 | any \l GridMesh object. |
| 657 | If a size value is assigned to this property, the ShaderEffect implicitly |
| 658 | uses a \l GridMesh with the value as |
| 659 | \l{GridMesh::resolution}{mesh resolution}. By default, this property is |
| 660 | the size 1x1. |
| 661 | |
| 662 | \sa GridMesh |
| 663 | */ |
| 664 | |
| 665 | QVariant QQuickShaderEffect::mesh() const |
| 666 | { |
| 667 | #if QT_CONFIG(opengl) |
| 668 | if (m_glImpl) |
| 669 | return m_glImpl->mesh(); |
| 670 | #endif |
| 671 | return m_impl->mesh(); |
| 672 | } |
| 673 | |
| 674 | void QQuickShaderEffect::setMesh(const QVariant &mesh) |
| 675 | { |
| 676 | #if QT_CONFIG(opengl) |
| 677 | if (m_glImpl) { |
| 678 | m_glImpl->setMesh(mesh); |
| 679 | return; |
| 680 | } |
| 681 | #endif |
| 682 | m_impl->setMesh(mesh); |
| 683 | } |
| 684 | |
| 685 | /*! |
| 686 | \qmlproperty enumeration QtQuick::ShaderEffect::cullMode |
| 687 | |
| 688 | This property defines which sides of the item should be visible. |
| 689 | |
| 690 | \list |
| 691 | \li ShaderEffect.NoCulling - Both sides are visible |
| 692 | \li ShaderEffect.BackFaceCulling - only front side is visible |
| 693 | \li ShaderEffect.FrontFaceCulling - only back side is visible |
| 694 | \endlist |
| 695 | |
| 696 | The default is NoCulling. |
| 697 | */ |
| 698 | |
| 699 | QQuickShaderEffect::CullMode QQuickShaderEffect::cullMode() const |
| 700 | { |
| 701 | #if QT_CONFIG(opengl) |
| 702 | if (m_glImpl) |
| 703 | return m_glImpl->cullMode(); |
| 704 | #endif |
| 705 | return m_impl->cullMode(); |
| 706 | } |
| 707 | |
| 708 | void QQuickShaderEffect::setCullMode(CullMode face) |
| 709 | { |
| 710 | #if QT_CONFIG(opengl) |
| 711 | if (m_glImpl) { |
| 712 | m_glImpl->setCullMode(face); |
| 713 | return; |
| 714 | } |
| 715 | #endif |
| 716 | return m_impl->setCullMode(face); |
| 717 | } |
| 718 | |
| 719 | /*! |
| 720 | \qmlproperty bool QtQuick::ShaderEffect::supportsAtlasTextures |
| 721 | |
| 722 | Set this property true to confirm that your shader code doesn't rely on |
| 723 | qt_MultiTexCoord0 ranging from (0,0) to (1,1) relative to the mesh. |
| 724 | In this case the range of qt_MultiTexCoord0 will rather be based on the position |
| 725 | of the texture within the atlas. This property currently has no effect if there |
| 726 | is less, or more, than one sampler uniform used as input to your shader. |
| 727 | |
| 728 | This differs from providing qt_SubRect_<name> uniforms in that the latter allows |
| 729 | drawing one or more textures from the atlas in a single ShaderEffect item, while |
| 730 | supportsAtlasTextures allows multiple instances of a ShaderEffect component using |
| 731 | a different source image from the atlas to be batched in a single draw. |
| 732 | Both prevent a texture from being copied out of the atlas when referenced by a ShaderEffect. |
| 733 | |
| 734 | The default value is false. |
| 735 | |
| 736 | \since 5.4 |
| 737 | \since QtQuick 2.4 |
| 738 | */ |
| 739 | |
| 740 | bool QQuickShaderEffect::supportsAtlasTextures() const |
| 741 | { |
| 742 | #if QT_CONFIG(opengl) |
| 743 | if (m_glImpl) |
| 744 | return m_glImpl->supportsAtlasTextures(); |
| 745 | #endif |
| 746 | return m_impl->supportsAtlasTextures(); |
| 747 | } |
| 748 | |
| 749 | void QQuickShaderEffect::setSupportsAtlasTextures(bool supports) |
| 750 | { |
| 751 | #if QT_CONFIG(opengl) |
| 752 | if (m_glImpl) { |
| 753 | m_glImpl->setSupportsAtlasTextures(supports); |
| 754 | return; |
| 755 | } |
| 756 | #endif |
| 757 | m_impl->setSupportsAtlasTextures(supports); |
| 758 | } |
| 759 | |
| 760 | /*! |
| 761 | \qmlproperty enumeration QtQuick::ShaderEffect::status |
| 762 | |
| 763 | This property tells the current status of the OpenGL shader program. |
| 764 | |
| 765 | \list |
| 766 | \li ShaderEffect.Compiled - the shader program was successfully compiled and linked. |
| 767 | \li ShaderEffect.Uncompiled - the shader program has not yet been compiled. |
| 768 | \li ShaderEffect.Error - the shader program failed to compile or link. |
| 769 | \endlist |
| 770 | |
| 771 | When setting the fragment or vertex shader source code, the status will |
| 772 | become Uncompiled. The first time the ShaderEffect is rendered with new |
| 773 | shader source code, the shaders are compiled and linked, and the status is |
| 774 | updated to Compiled or Error. |
| 775 | |
| 776 | When runtime compilation is not in use and the shader properties refer to |
| 777 | files with bytecode, the status is always Compiled. The contents of the |
| 778 | shader is not examined (apart from basic reflection to discover vertex |
| 779 | input elements and constant buffer data) until later in the rendering |
| 780 | pipeline so potential errors (like layout or root signature mismatches) |
| 781 | will only be detected at a later point. |
| 782 | |
| 783 | \sa log |
| 784 | */ |
| 785 | |
| 786 | /*! |
| 787 | \qmlproperty string QtQuick::ShaderEffect::log |
| 788 | |
| 789 | This property holds a log of warnings and errors from the latest attempt at |
| 790 | compiling and linking the OpenGL shader program. It is updated at the same |
| 791 | time \l status is set to Compiled or Error. |
| 792 | |
| 793 | \sa status |
| 794 | */ |
| 795 | |
| 796 | QString QQuickShaderEffect::log() const |
| 797 | { |
| 798 | #if QT_CONFIG(opengl) |
| 799 | if (m_glImpl) |
| 800 | return m_glImpl->log(); |
| 801 | #endif |
| 802 | return m_impl->log(); |
| 803 | } |
| 804 | |
| 805 | QQuickShaderEffect::Status QQuickShaderEffect::status() const |
| 806 | { |
| 807 | #if QT_CONFIG(opengl) |
| 808 | if (m_glImpl) |
| 809 | return m_glImpl->status(); |
| 810 | #endif |
| 811 | return m_impl->status(); |
| 812 | } |
| 813 | |
| 814 | bool QQuickShaderEffect::event(QEvent *e) |
| 815 | { |
| 816 | #if QT_CONFIG(opengl) |
| 817 | if (m_glImpl) { |
| 818 | m_glImpl->handleEvent(e); |
| 819 | return QQuickItem::event(e); |
| 820 | } |
| 821 | #endif |
| 822 | if (m_impl) |
| 823 | m_impl->handleEvent(e); |
| 824 | return QQuickItem::event(e); |
| 825 | } |
| 826 | |
| 827 | void QQuickShaderEffect::geometryChanged(const QRectF &newGeometry, const QRectF &oldGeometry) |
| 828 | { |
| 829 | #if QT_CONFIG(opengl) |
| 830 | if (m_glImpl) { |
| 831 | m_glImpl->handleGeometryChanged(newGeometry, oldGeometry); |
| 832 | QQuickItem::geometryChanged(newGeometry, oldGeometry); |
| 833 | return; |
| 834 | } |
| 835 | #endif |
| 836 | m_impl->handleGeometryChanged(newGeometry, oldGeometry); |
| 837 | QQuickItem::geometryChanged(newGeometry, oldGeometry); |
| 838 | } |
| 839 | |
| 840 | QSGNode *QQuickShaderEffect::updatePaintNode(QSGNode *oldNode, UpdatePaintNodeData *updatePaintNodeData) |
| 841 | { |
| 842 | #if QT_CONFIG(opengl) |
| 843 | if (m_glImpl) |
| 844 | return m_glImpl->handleUpdatePaintNode(oldNode, updatePaintNodeData); |
| 845 | #endif |
| 846 | return m_impl->handleUpdatePaintNode(oldNode, updatePaintNodeData); |
| 847 | } |
| 848 | |
| 849 | void QQuickShaderEffect::componentComplete() |
| 850 | { |
| 851 | #if QT_CONFIG(opengl) |
| 852 | if (m_glImpl) { |
| 853 | m_glImpl->maybeUpdateShaders(); |
| 854 | QQuickItem::componentComplete(); |
| 855 | return; |
| 856 | } |
| 857 | #endif |
| 858 | m_impl->maybeUpdateShaders(); |
| 859 | QQuickItem::componentComplete(); |
| 860 | } |
| 861 | |
| 862 | void QQuickShaderEffect::itemChange(ItemChange change, const ItemChangeData &value) |
| 863 | { |
| 864 | #if QT_CONFIG(opengl) |
| 865 | if (m_glImpl) { |
| 866 | m_glImpl->handleItemChange(change, value); |
| 867 | QQuickItem::itemChange(change, value); |
| 868 | return; |
| 869 | } |
| 870 | #endif |
| 871 | // It's possible for itemChange to be called during destruction when deleting |
| 872 | // the QQuickShaderEffectImpl. We nullify m_impl before deleting it via another pointer |
| 873 | // to it, so we must check that it's not null before trying to use it here. |
| 874 | if (m_impl) |
| 875 | m_impl->handleItemChange(change, value); |
| 876 | QQuickItem::itemChange(change, value); |
| 877 | } |
| 878 | |
| 879 | bool QQuickShaderEffect::isComponentComplete() const |
| 880 | { |
| 881 | return QQuickItem::isComponentComplete(); |
| 882 | } |
| 883 | |
| 884 | QString QQuickShaderEffect::parseLog() // for OpenGL-based autotests |
| 885 | { |
| 886 | #if QT_CONFIG(opengl) |
| 887 | if (m_glImpl) |
| 888 | return m_glImpl->parseLog(); |
| 889 | #endif |
| 890 | return m_impl->parseLog(); |
| 891 | } |
| 892 | |
| 893 | void QQuickShaderEffectPrivate::updatePolish() |
| 894 | { |
| 895 | Q_Q(QQuickShaderEffect); |
| 896 | if (!qmlEngine(q)) |
| 897 | return; |
| 898 | #if QT_CONFIG(opengl) |
| 899 | if (q->m_glImpl) { |
| 900 | q->m_glImpl->maybeUpdateShaders(); |
| 901 | return; |
| 902 | } |
| 903 | #endif |
| 904 | q->m_impl->maybeUpdateShaders(); |
| 905 | } |
| 906 | |
| 907 | #if QT_CONFIG(opengl) |
| 908 | bool QQuickShaderEffect::isOpenGLShaderEffect() const |
| 909 | { |
| 910 | return m_glImpl != nullptr; |
| 911 | } |
| 912 | #endif |
| 913 | |
| 914 | QT_END_NAMESPACE |
| 915 | |
| 916 | #include "moc_qquickshadereffect_p.cpp" |
| 917 | |