[Mesa-dev] [PATCH 3/7] dri: Define DRI_MutableRenderBuffer extensions
Chad Versace
chadversary at chromium.org
Tue Jul 31 18:18:05 UTC 2018
Define extensions DRI_MutableRenderBufferDriver and
DRI_MutableRenderBufferLoader. These are the two halves for
EGL_KHR_mutable_render_buffer.
Outside the DRI code there is one additional change. Add
gl_config::mutableRenderBuffer to match
__DRI_ATTRIB_MUTABLE_RENDER_BUFFER. Neither are used yet.
---
include/GL/internal/dri_interface.h | 138 ++++++++++++++++++++++++-
src/mesa/drivers/dri/common/dri_util.c | 2 +
src/mesa/drivers/dri/common/dri_util.h | 4 +
src/mesa/drivers/dri/common/utils.c | 1 +
src/mesa/main/mtypes.h | 3 +
5 files changed, 145 insertions(+), 3 deletions(-)
diff --git a/include/GL/internal/dri_interface.h b/include/GL/internal/dri_interface.h
index c32cdd3767a..245c845832b 100644
--- a/include/GL/internal/dri_interface.h
+++ b/include/GL/internal/dri_interface.h
@@ -48,6 +48,7 @@ typedef unsigned int drm_drawable_t;
typedef struct drm_clip_rect drm_clip_rect_t;
#endif
+#include <stdbool.h>
#include <stdint.h>
/**
@@ -746,7 +747,8 @@ struct __DRIuseInvalidateExtensionRec {
#define __DRI_ATTRIB_BIND_TO_TEXTURE_TARGETS 46
#define __DRI_ATTRIB_YINVERTED 47
#define __DRI_ATTRIB_FRAMEBUFFER_SRGB_CAPABLE 48
-#define __DRI_ATTRIB_MAX (__DRI_ATTRIB_FRAMEBUFFER_SRGB_CAPABLE + 1)
+#define __DRI_ATTRIB_MUTABLE_RENDER_BUFFER 49 /* EGL_MUTABLE_RENDER_BUFFER_BIT_KHR */
+#define __DRI_ATTRIB_MAX 50
/* __DRI_ATTRIB_RENDER_TYPE */
#define __DRI_ATTRIB_RGBA_BIT 0x01
@@ -1888,9 +1890,57 @@ struct __DRI2rendererQueryExtensionRec {
* Image Loader extension. Drivers use this to allocate color buffers
*/
+/**
+ * See __DRIimageLoaderExtensionRec::getBuffers::buffer_mask.
+ */
enum __DRIimageBufferMask {
__DRI_IMAGE_BUFFER_BACK = (1 << 0),
- __DRI_IMAGE_BUFFER_FRONT = (1 << 1)
+ __DRI_IMAGE_BUFFER_FRONT = (1 << 1),
+
+ /**
+ * A buffer shared between application and compositor. The buffer may be
+ * simultaneously accessed by each.
+ *
+ * A shared buffer is equivalent to an EGLSurface whose EGLConfig contains
+ * EGL_MUTABLE_RENDER_BUFFER_BIT_KHR and whose active EGL_RENDER_BUFFER (as
+ * opposed to any pending, requested change to EGL_RENDER_BUFFER) is
+ * EGL_SINGLE_BUFFER.
+ *
+ * If buffer_mask contains __DRI_IMAGE_BUFFER_SHARED, then must contains no
+ * other bits. As a corollary, a __DRIdrawable that has a "shared" buffer
+ * has no front nor back buffer.
+ *
+ * The loader returns __DRI_IMAGE_BUFFER_SHARED in buffer_mask if and only
+ * if:
+ * - The loader supports __DRI_MUTABLE_RENDER_BUFFER_LOADER.
+ * - The driver supports __DRI_MUTABLE_RENDER_BUFFER_DRIVER.
+ * - The EGLConfig of the drawable EGLSurface contains
+ * EGL_MUTABLE_RENDER_BUFFER_BIT_KHR.
+ * - The EGLContext's EGL_RENDER_BUFFER is EGL_SINGLE_BUFFER.
+ * Equivalently, the EGLSurface's active EGL_RENDER_BUFFER (as
+ * opposed to any pending, requested change to EGL_RENDER_BUFFER) is
+ * EGL_SINGLE_BUFFER. (See the EGL 1.5 and
+ * EGL_KHR_mutable_render_buffer spec for details about "pending" vs
+ * "active" EGL_RENDER_BUFFER state).
+ *
+ * A shared buffer is similar to a front buffer in that all rendering to the
+ * buffer should appear promptly on the screen. It is different from
+ * a front buffer in that its behavior is independent from the
+ * GL_DRAW_BUFFER state. Specifically, if GL_DRAW_FRAMEBUFFER is 0 and the
+ * __DRIdrawable's buffer_mask is __DRI_IMAGE_BUFFER_SHARED, then all
+ * rendering should appear promptly on the screen if GL_DRAW_BUFFER is not
+ * GL_NONE.
+ *
+ * The difference between a shared buffer and a front buffer is motivated
+ * by the constraints of Android and OpenGL ES. OpenGL ES does not support
+ * front-buffer rendering. Android's SurfaceFlinger protocol provides the
+ * EGL driver only a back buffer and no front buffer. The shared buffer
+ * mode introduced by EGL_KHR_mutable_render_buffer is a backdoor though
+ * EGL that allows Android OpenGL ES applications to render to what is
+ * effectively the front buffer, a backdoor that required no change to the
+ * OpenGL ES API and little change to the SurfaceFlinger API.
+ */
+ __DRI_IMAGE_BUFFER_SHARED = (1 << 2),
};
struct __DRIimageList {
@@ -1915,7 +1965,8 @@ struct __DRIimageLoaderExtensionRec {
* \param stamp Address of variable to be updated when
* getBuffers must be called again
* \param loaderPrivate The loaderPrivate for driDrawable
- * \param buffer_mask Set of buffers to allocate
+ * \param buffer_mask Set of buffers to allocate. A bitmask of
+ * __DRIimageBufferMask.
* \param buffers Returned buffers
*/
int (*getBuffers)(__DRIdrawable *driDrawable,
@@ -2029,4 +2080,85 @@ struct __DRIbackgroundCallableExtensionRec {
GLboolean (*isThreadSafe)(void *loaderPrivate);
};
+/**
+ * The driver portion of EGL_KHR_mutable_render_buffer.
+ *
+ * If the driver creates a __DRIconfig with
+ * __DRI_ATTRIB_MUTABLE_RENDER_BUFFER, then it must support this extension.
+ *
+ * To support this extension:
+ *
+ * - The driver should create at least one __DRIconfig with
+ * __DRI_ATTRIB_MUTABLE_RENDER_BUFFER. This is strongly recommended but
+ * not required.
+ *
+ * - The driver must be able to handle __DRI_IMAGE_BUFFER_SHARED if
+ * returned by __DRIimageLoaderExtension:getBuffers().
+ *
+ * - When rendering to __DRI_IMAGE_BUFFER_SHARED, it must call
+ * __DRImutableRenderBufferLoaderExtension::displaySharedBuffer() in
+ * response to glFlush and glFinish. (This requirement is not documented
+ * in EGL_KHR_mutable_render_buffer, but is a de-facto requirement in the
+ * Android ecosystem. Android applications expect that glFlush will
+ * immediately display the buffer when in shared buffer mode, and Android
+ * drivers comply with this expectation). It :may: call
+ * displaySharedBuffer() more often than required.
+ *
+ * - When rendering to __DRI_IMAGE_BUFFER_SHARED, it must ensure that the
+ * buffer is always in a format compatible for display because the
+ * display engine (usually SurfaceFlinger or hwcomposer) may display the
+ * image at any time, even concurrently with 3D rendering. For example,
+ * display hardware and the GL hardware may be able to access the buffer
+ * simultaneously. In particular, if the buffer is compressed then take
+ * care that SurfaceFlinger and hwcomposer can consume the compression
+ * format.
+ *
+ * \see __DRI_IMAGE_BUFFER_SHARED
+ * \see __DRI_ATTRIB_MUTABLE_RENDER_BUFFER
+ * \see __DRI_MUTABLE_RENDER_BUFFER_LOADER
+ */
+#define __DRI_MUTABLE_RENDER_BUFFER_DRIVER "DRI_MutableRenderBufferDriver"
+#define __DRI_MUTABLE_RENDER_BUFFER_DRIVER_VERSION 1
+
+typedef struct __DRImutableRenderBufferDriverExtensionRec __DRImutableRenderBufferDriverExtension;
+struct __DRImutableRenderBufferDriverExtensionRec {
+ __DRIextension base;
+};
+
+/**
+ * The loader portion of EGL_KHR_mutable_render_buffer.
+ *
+ * Requires loader extension DRI_IMAGE_LOADER, through which the loader sends
+ * __DRI_IMAGE_BUFFER_SHARED to the driver.
+ *
+ * \see __DRI_MUTABLE_RENDER_BUFFER_DRIVER
+ */
+#define __DRI_MUTABLE_RENDER_BUFFER_LOADER "DRI_MutableRenderBufferLoader"
+#define __DRI_MUTABLE_RENDER_BUFFER_LOADER_VERSION 1
+
+typedef struct __DRImutableRenderBufferLoaderExtensionRec __DRImutableRenderBufferLoaderExtension;
+struct __DRImutableRenderBufferLoaderExtensionRec {
+ __DRIextension base;
+
+ /**
+ * Inform the display engine (that is, SurfaceFlinger and/or hwcomposer)
+ * that the __DRIdrawable has new content.
+ *
+ * The display engine may ignore this call, for example, if it continually
+ * refreshes and displays the buffer on every frame, as in
+ * EGL_ANDROID_front_buffer_auto_refresh. On the other extreme, the display
+ * engine may refresh and display the buffer only in frames in which the
+ * driver calls this.
+ *
+ * If the fence_fd is not -1, then the display engine will display the
+ * buffer only after the fence signals.
+ *
+ * The drawable's current __DRIimageBufferMask, as returned by
+ * __DRIimageLoaderExtension::getBuffers(), must be
+ * __DRI_IMAGE_BUFFER_SHARED.
+ */
+ void (*displaySharedBuffer)(__DRIdrawable *drawable, int fence_fd,
+ void *loaderPrivate);
+};
+
#endif
diff --git a/src/mesa/drivers/dri/common/dri_util.c b/src/mesa/drivers/dri/common/dri_util.c
index d257cb644c8..be7b6e5535d 100644
--- a/src/mesa/drivers/dri/common/dri_util.c
+++ b/src/mesa/drivers/dri/common/dri_util.c
@@ -81,6 +81,8 @@ setupLoaderExtensions(__DRIscreen *psp,
psp->swrast_loader = (__DRIswrastLoaderExtension *) extensions[i];
if (strcmp(extensions[i]->name, __DRI_IMAGE_LOADER) == 0)
psp->image.loader = (__DRIimageLoaderExtension *) extensions[i];
+ if (strcmp(extensions[i]->name, __DRI_MUTABLE_RENDER_BUFFER_LOADER) == 0)
+ psp->mutableRenderBuffer.loader = (__DRImutableRenderBufferLoaderExtension *) extensions[i];
}
}
diff --git a/src/mesa/drivers/dri/common/dri_util.h b/src/mesa/drivers/dri/common/dri_util.h
index 062c83f79ec..d6c7d07d4e0 100644
--- a/src/mesa/drivers/dri/common/dri_util.h
+++ b/src/mesa/drivers/dri/common/dri_util.h
@@ -216,6 +216,10 @@ struct __DRIscreenRec {
const __DRIimageLoaderExtension *loader;
} image;
+ struct {
+ const __DRImutableRenderBufferLoaderExtension *loader;
+ } mutableRenderBuffer;
+
driOptionCache optionInfo;
driOptionCache optionCache;
diff --git a/src/mesa/drivers/dri/common/utils.c b/src/mesa/drivers/dri/common/utils.c
index fc5e2d19f34..86169d5c214 100644
--- a/src/mesa/drivers/dri/common/utils.c
+++ b/src/mesa/drivers/dri/common/utils.c
@@ -409,6 +409,7 @@ static const struct { unsigned int attrib, offset; } attribMap[] = {
__ATTRIB(__DRI_ATTRIB_BIND_TO_TEXTURE_TARGETS, bindToTextureTargets),
__ATTRIB(__DRI_ATTRIB_YINVERTED, yInverted),
__ATTRIB(__DRI_ATTRIB_FRAMEBUFFER_SRGB_CAPABLE, sRGBCapable),
+ __ATTRIB(__DRI_ATTRIB_MUTABLE_RENDER_BUFFER, mutableRenderBuffer),
/* The struct field doesn't matter here, these are handled by the
* switch in driGetConfigAttribIndex. We need them in the array
diff --git a/src/mesa/main/mtypes.h b/src/mesa/main/mtypes.h
index d71872835d1..7f7aab09adb 100644
--- a/src/mesa/main/mtypes.h
+++ b/src/mesa/main/mtypes.h
@@ -213,6 +213,9 @@ struct gl_config
/* EXT_framebuffer_sRGB */
GLint sRGBCapable;
+
+ /* EGL_KHR_mutable_render_buffer */
+ GLuint mutableRenderBuffer; /* bool */
};
--
2.18.0.345.g5c9ce644c3-goog
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