Files
MapLibreParticleLab/include/mbgl/style/layers/custom_layer_host.hpp
Steve Gifford 49f80e95f3 Changes to the custom Metal layer to allow more flexible rendering (#4446)
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: louwers <649392+louwers@users.noreply.github.com>
Co-authored-by: Bart Louwers <bart@emeel.net>
2026-08-12 00:23:35 +02:00

66 lines
2.5 KiB
C++

#pragma once
#include <mbgl/gfx/context.hpp>
#include <mbgl/style/layers/custom_layer_init_parameters.hpp>
#include <mbgl/style/layers/custom_layer_render_parameters.hpp>
namespace mbgl {
namespace style {
class CustomLayerHost {
public:
virtual ~CustomLayerHost() = default;
/**
* Initialize any GL/Metal/Vulkan state needed by the custom layer. This method
* is called once, from the main thread, at a point when the graphics context
* is active but before rendering for the first time.
*
* The parameters argument provides backend-specific device handles:
* - Vulkan: cast to mbgl::style::vulkan::CustomLayerInitParameters for
* access to vk::Device, vk::PhysicalDevice, and the dispatcher.
* - Metal/GL: base CustomLayerInitParameters (no extra handles currently).
*
* Resources that are acquired in this method must be released in the
* `deinitialize` function.
*/
virtual void initialize(const CustomLayerInitParameters&) = 0;
/**
* Called right before the layers start rendering.
*/
virtual void preRender(const mbgl::gfx::Context&, const mbgl::style::CustomLayerRenderParameters&) {};
/**
* Render the layer. This method is called once per frame. The
* implementation should not make any assumptions about the GL/Metal state (other
* than that the correct context is active). It may make changes to the
* state, and is not required to reset values such as the depth mask,
* stencil mask, and corresponding test flags to their original values. Make
* sure that you are drawing your fragments with a z value of 1 to take
* advantage of the opaque fragment culling in case there are opaque layers
* above your custom layer.
*/
virtual void render(const mbgl::style::CustomLayerRenderParameters&) = 0;
/**
* Called when the system has destroyed the underlying GL/Metal context. The
* `deinitialize` function will not be called in this case, however
* `initialize` will be called instead to prepare for a new render.
*
*/
virtual void contextLost() = 0;
/**
* Destroy any GL/Metal state needed by the custom layer, and deallocate context,
* if necessary. This method is called once, from the main thread, at a
* point when the GL/Metal context is active.
*
* Note that it may be called even when the `initialize` function has not
* been called.
*/
virtual void deinitialize() = 0;
};
} // namespace style
} // namespace mbgl