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QRhiViewport Class

Specifies a viewport rectangle. More...

Header: #include <rhi/qrhi.h>
CMake: find_package(Qt6 REQUIRED COMPONENTS Gui)
target_link_libraries(mytarget PRIVATE Qt6::GuiPrivate)
qmake: QT += gui-private
Since: Qt 6.6

Public Functions

QRhiViewport()
QRhiViewport(float x, float y, float w, float h, float minDepth = 0.0f, float maxDepth = 1.0f)
float maxDepth() const
float minDepth() const
void setMaxDepth(float maxDepth)
void setMinDepth(float minDepth)
void setViewport(float x, float y, float w, float h)
std::array<float, 4> viewport() const
size_t qHash(const QRhiViewport &key, size_t seed = 0)
bool operator!=(const QRhiViewport &a, const QRhiViewport &b)
bool operator==(const QRhiViewport &a, const QRhiViewport &b)

Detailed Description

Used with QRhiCommandBuffer::setViewport().

QRhi assumes OpenGL-style viewport coordinates, meaning x and y are bottom-left. Negative width or height are not allowed.

Typical usage is like the following:

const QSize outputSizeInPixels = swapchain->currentPixelSize();
const QRhiViewport viewport(0, 0, outputSizeInPixels.width(), outputSizeInPixels.height());
cb->beginPass(swapchain->currentFrameRenderTarget(), Qt::black, { 1.0f, 0 });
cb->setGraphicsPipeline(ps);
cb->setViewport(viewport);
// ...

Note: This is a RHI API with limited compatibility guarantees, see QRhi for details.

See also QRhiCommandBuffer::setViewport(), QRhi::clipSpaceCorrMatrix(), and QRhiScissor.

Member Function Documentation

[constexpr noexcept] QRhiViewport::QRhiViewport()

Constructs a viewport description with an empty rectangle and a depth range of 0.0f - 1.0f.

See also QRhi::clipSpaceCorrMatrix().

QRhiViewport::QRhiViewport(float x, float y, float w, float h, float minDepth = 0.0f, float maxDepth = 1.0f)

Constructs a viewport description with the rectangle specified by x, y, w, h and the depth range minDepth and maxDepth.

Note: x and y are assumed to be the bottom-left position. w and h should not be negative, the viewport will be ignored by QRhiCommandBuffer::setViewport() otherwise.

See also QRhi::clipSpaceCorrMatrix().

float QRhiViewport::maxDepth() const

Returns the maxDepth value of the depth range of the viewport.

See also setMaxDepth().

float QRhiViewport::minDepth() const

Returns the minDepth value of the depth range of the viewport.

See also setMinDepth().

void QRhiViewport::setMaxDepth(float maxDepth)

Sets the maxDepth of the depth range of the viewport. By default this is set to 1.0f.

See also maxDepth().

void QRhiViewport::setMinDepth(float minDepth)

Sets the minDepth of the depth range of the viewport. By default this is set to 0.0f.

See also minDepth().

void QRhiViewport::setViewport(float x, float y, float w, float h)

Sets the viewport's position and size to x, y, w, and h.

Note: Viewports are specified in a coordinate system that has its origin in the bottom-left.

See also viewport().

std::array<float, 4> QRhiViewport::viewport() const

Returns the viewport x, y, width, and height.

See also setViewport().

Related Non-Members

[noexcept] size_t qHash(const QRhiViewport &key, size_t seed = 0)

Returns the hash value for key, using seed to seed the calculation.

[noexcept] bool operator!=(const QRhiViewport &a, const QRhiViewport &b)

Returns false if the values in the two QRhiViewport objects a and b are equal; otherwise returns true.

[noexcept] bool operator==(const QRhiViewport &a, const QRhiViewport &b)

Returns true if the values in the two QRhiViewport objects a and b are equal.

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