libweston: Add pixel-format helpers

Rather than duplicating knowledge of pixel formats across several
components, create a custom central repository.

Signed-off-by: Daniel Stone <daniels@collabora.com>
[Pekka: fix include paths and two copy-pastas]
Reviewed-by: Pekka Paalanen <pekka.paalanen@collabora.co.uk>
diff --git a/libweston/pixel-formats.c b/libweston/pixel-formats.c
new file mode 100644
index 0000000..df84a9f
--- /dev/null
+++ b/libweston/pixel-formats.c
@@ -0,0 +1,430 @@
+/*
+ * Copyright © 2016 Collabora, Ltd.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ *
+ * Author: Daniel Stone <daniels@collabora.com>
+ */
+
+#include "config.h"
+
+#include <endian.h>
+#include <inttypes.h>
+#include <stdbool.h>
+#include <unistd.h>
+#include <drm_fourcc.h>
+
+#include "helpers.h"
+#include "wayland-util.h"
+#include "pixel-formats.h"
+
+#if ENABLE_EGL
+#include <EGL/egl.h>
+#include <EGL/eglext.h>
+#include <GLES2/gl2.h>
+#include <GLES2/gl2ext.h>
+#define GL_FORMAT(fmt) .gl_format = (fmt)
+#define GL_TYPE(type) .gl_type = (type)
+#define SAMPLER_TYPE(type) .sampler_type = (type)
+#else
+#define GL_FORMAT(fmt) .gl_format = 0
+#define GL_TYPE(type) .gl_type = 0
+#define SAMPLER_TYPE(type) .sampler_type = 0
+#endif
+
+#include "weston-egl-ext.h"
+
+/**
+ * Table of DRM formats supported by Weston; RGB, ARGB and YUV formats are
+ * supported. Indexed/greyscale formats, and formats not containing complete
+ * colour channels, are not supported.
+ */
+static const struct pixel_format_info pixel_format_table[] = {
+	{
+		.format = DRM_FORMAT_XRGB4444,
+	},
+	{
+		.format = DRM_FORMAT_ARGB4444,
+		.opaque_substitute = DRM_FORMAT_XRGB4444,
+	},
+	{
+		.format = DRM_FORMAT_XBGR4444,
+	},
+	{
+		.format = DRM_FORMAT_ABGR4444,
+		.opaque_substitute = DRM_FORMAT_XBGR4444,
+	},
+	{
+		.format = DRM_FORMAT_RGBX4444,
+# if __BYTE_ORDER == __LITTLE_ENDIAN
+		GL_FORMAT(GL_RGBA),
+		GL_TYPE(GL_UNSIGNED_SHORT_4_4_4_4),
+#endif
+	},
+	{
+		.format = DRM_FORMAT_RGBA4444,
+		.opaque_substitute = DRM_FORMAT_RGBX4444,
+# if __BYTE_ORDER == __LITTLE_ENDIAN
+		GL_FORMAT(GL_RGBA),
+		GL_TYPE(GL_UNSIGNED_SHORT_4_4_4_4),
+#endif
+	},
+	{
+		.format = DRM_FORMAT_BGRX4444,
+	},
+	{
+		.format = DRM_FORMAT_BGRA4444,
+		.opaque_substitute = DRM_FORMAT_BGRX4444,
+	},
+	{
+		.format = DRM_FORMAT_XRGB1555,
+		.depth = 15,
+		.bpp = 16,
+	},
+	{
+		.format = DRM_FORMAT_ARGB1555,
+		.opaque_substitute = DRM_FORMAT_XRGB1555,
+	},
+	{
+		.format = DRM_FORMAT_XBGR1555,
+	},
+	{
+		.format = DRM_FORMAT_ABGR1555,
+		.opaque_substitute = DRM_FORMAT_XBGR1555,
+	},
+	{
+		.format = DRM_FORMAT_RGBX5551,
+# if __BYTE_ORDER == __LITTLE_ENDIAN
+		GL_FORMAT(GL_RGBA),
+		GL_TYPE(GL_UNSIGNED_SHORT_5_5_5_1),
+#endif
+	},
+	{
+		.format = DRM_FORMAT_RGBA5551,
+		.opaque_substitute = DRM_FORMAT_RGBX5551,
+# if __BYTE_ORDER == __LITTLE_ENDIAN
+		GL_FORMAT(GL_RGBA),
+		GL_TYPE(GL_UNSIGNED_SHORT_5_5_5_1),
+#endif
+	},
+	{
+		.format = DRM_FORMAT_BGRX5551,
+	},
+	{
+		.format = DRM_FORMAT_BGRA5551,
+		.opaque_substitute = DRM_FORMAT_BGRX5551,
+	},
+	{
+		.format = DRM_FORMAT_RGB565,
+		.depth = 16,
+		.bpp = 16,
+# if __BYTE_ORDER == __LITTLE_ENDIAN
+		GL_FORMAT(GL_RGB),
+		GL_TYPE(GL_UNSIGNED_SHORT_5_6_5),
+#endif
+	},
+	{
+		.format = DRM_FORMAT_BGR565,
+	},
+	{
+		.format = DRM_FORMAT_RGB888,
+	},
+	{
+		.format = DRM_FORMAT_BGR888,
+		GL_FORMAT(GL_RGB),
+		GL_TYPE(GL_UNSIGNED_BYTE),
+	},
+	{
+		.format = DRM_FORMAT_XRGB8888,
+		.depth = 24,
+		.bpp = 32,
+		GL_FORMAT(GL_BGRA_EXT),
+		GL_TYPE(GL_UNSIGNED_BYTE),
+	},
+	{
+		.format = DRM_FORMAT_ARGB8888,
+		.opaque_substitute = DRM_FORMAT_XRGB8888,
+		.depth = 32,
+		.bpp = 32,
+		GL_FORMAT(GL_BGRA_EXT),
+		GL_TYPE(GL_UNSIGNED_BYTE),
+	},
+	{
+		.format = DRM_FORMAT_XBGR8888,
+		GL_FORMAT(GL_RGBA),
+		GL_TYPE(GL_UNSIGNED_BYTE),
+	},
+	{
+		.format = DRM_FORMAT_ABGR8888,
+		.opaque_substitute = DRM_FORMAT_XBGR8888,
+		GL_FORMAT(GL_RGBA),
+		GL_TYPE(GL_UNSIGNED_BYTE),
+	},
+	{
+		.format = DRM_FORMAT_RGBX8888,
+	},
+	{
+		.format = DRM_FORMAT_RGBA8888,
+		.opaque_substitute = DRM_FORMAT_RGBX8888,
+	},
+	{
+		.format = DRM_FORMAT_BGRX8888,
+	},
+	{
+		.format = DRM_FORMAT_BGRA8888,
+		.opaque_substitute = DRM_FORMAT_BGRX8888,
+	},
+	{
+		.format = DRM_FORMAT_XRGB2101010,
+		.depth = 30,
+		.bpp = 32,
+	},
+	{
+		.format = DRM_FORMAT_ARGB2101010,
+		.opaque_substitute = DRM_FORMAT_XRGB2101010,
+	},
+	{
+		.format = DRM_FORMAT_XBGR2101010,
+# if __BYTE_ORDER == __LITTLE_ENDIAN
+		GL_FORMAT(GL_RGBA),
+		GL_TYPE(GL_UNSIGNED_INT_2_10_10_10_REV_EXT),
+#endif
+	},
+	{
+		.format = DRM_FORMAT_ABGR2101010,
+		.opaque_substitute = DRM_FORMAT_XBGR2101010,
+# if __BYTE_ORDER == __LITTLE_ENDIAN
+		GL_FORMAT(GL_RGBA),
+		GL_TYPE(GL_UNSIGNED_INT_2_10_10_10_REV_EXT),
+#endif
+	},
+	{
+		.format = DRM_FORMAT_RGBX1010102,
+	},
+	{
+		.format = DRM_FORMAT_RGBA1010102,
+		.opaque_substitute = DRM_FORMAT_RGBX1010102,
+	},
+	{
+		.format = DRM_FORMAT_BGRX1010102,
+	},
+	{
+		.format = DRM_FORMAT_BGRA1010102,
+		.opaque_substitute = DRM_FORMAT_BGRX1010102,
+	},
+	{
+		.format = DRM_FORMAT_YUYV,
+		SAMPLER_TYPE(EGL_TEXTURE_Y_XUXV_WL),
+		.num_planes = 1,
+		.hsub = 2,
+	},
+	{
+		.format = DRM_FORMAT_YVYU,
+		SAMPLER_TYPE(EGL_TEXTURE_Y_XUXV_WL),
+		.num_planes = 1,
+		.chroma_order = ORDER_VU,
+		.hsub = 2,
+	},
+	{
+		.format = DRM_FORMAT_UYVY,
+		SAMPLER_TYPE(EGL_TEXTURE_Y_XUXV_WL),
+		.num_planes = 1,
+		.luma_chroma_order = ORDER_CHROMA_LUMA,
+		.hsub = 2,
+	},
+	{
+		.format = DRM_FORMAT_VYUY,
+		SAMPLER_TYPE(EGL_TEXTURE_Y_XUXV_WL),
+		.num_planes = 1,
+		.luma_chroma_order = ORDER_CHROMA_LUMA,
+		.chroma_order = ORDER_VU,
+		.hsub = 2,
+	},
+	{
+		.format = DRM_FORMAT_NV12,
+		SAMPLER_TYPE(EGL_TEXTURE_Y_UV_WL),
+		.num_planes = 2,
+		.hsub = 2,
+		.vsub = 2,
+	},
+	{
+		.format = DRM_FORMAT_NV21,
+		SAMPLER_TYPE(EGL_TEXTURE_Y_UV_WL),
+		.num_planes = 2,
+		.chroma_order = ORDER_VU,
+		.hsub = 2,
+		.vsub = 2,
+	},
+	{
+		.format = DRM_FORMAT_NV16,
+		SAMPLER_TYPE(EGL_TEXTURE_Y_UV_WL),
+		.num_planes = 2,
+		.hsub = 2,
+		.vsub = 1,
+	},
+	{
+		.format = DRM_FORMAT_NV61,
+		SAMPLER_TYPE(EGL_TEXTURE_Y_UV_WL),
+		.num_planes = 2,
+		.chroma_order = ORDER_VU,
+		.hsub = 2,
+		.vsub = 1,
+	},
+	{
+		.format = DRM_FORMAT_NV24,
+		SAMPLER_TYPE(EGL_TEXTURE_Y_UV_WL),
+		.num_planes = 2,
+	},
+	{
+		.format = DRM_FORMAT_NV42,
+		SAMPLER_TYPE(EGL_TEXTURE_Y_UV_WL),
+		.num_planes = 2,
+		.chroma_order = ORDER_VU,
+	},
+	{
+		.format = DRM_FORMAT_YUV410,
+		SAMPLER_TYPE(EGL_TEXTURE_Y_U_V_WL),
+		.num_planes = 3,
+		.hsub = 4,
+		.vsub = 4,
+	},
+	{
+		.format = DRM_FORMAT_YVU410,
+		SAMPLER_TYPE(EGL_TEXTURE_Y_U_V_WL),
+		.num_planes = 3,
+		.chroma_order = ORDER_VU,
+		.hsub = 4,
+		.vsub = 4,
+	},
+	{
+		.format = DRM_FORMAT_YUV411,
+		SAMPLER_TYPE(EGL_TEXTURE_Y_U_V_WL),
+		.num_planes = 3,
+		.hsub = 4,
+		.vsub = 1,
+	},
+	{
+		.format = DRM_FORMAT_YVU411,
+		SAMPLER_TYPE(EGL_TEXTURE_Y_U_V_WL),
+		.num_planes = 3,
+		.chroma_order = ORDER_VU,
+		.hsub = 4,
+		.vsub = 1,
+	},
+	{
+		.format = DRM_FORMAT_YUV420,
+		SAMPLER_TYPE(EGL_TEXTURE_Y_U_V_WL),
+		.num_planes = 3,
+		.hsub = 2,
+		.vsub = 2,
+	},
+	{
+		.format = DRM_FORMAT_YVU420,
+		SAMPLER_TYPE(EGL_TEXTURE_Y_U_V_WL),
+		.num_planes = 3,
+		.chroma_order = ORDER_VU,
+		.hsub = 2,
+		.vsub = 2,
+	},
+	{
+		.format = DRM_FORMAT_YUV422,
+		SAMPLER_TYPE(EGL_TEXTURE_Y_U_V_WL),
+		.num_planes = 3,
+		.hsub = 2,
+		.vsub = 1,
+	},
+	{
+		.format = DRM_FORMAT_YVU422,
+		SAMPLER_TYPE(EGL_TEXTURE_Y_U_V_WL),
+		.num_planes = 3,
+		.chroma_order = ORDER_VU,
+		.hsub = 2,
+		.vsub = 1,
+	},
+	{
+		.format = DRM_FORMAT_YUV444,
+		SAMPLER_TYPE(EGL_TEXTURE_Y_U_V_WL),
+		.num_planes = 3,
+	},
+	{
+		.format = DRM_FORMAT_YVU444,
+		SAMPLER_TYPE(EGL_TEXTURE_Y_U_V_WL),
+		.num_planes = 3,
+		.chroma_order = ORDER_VU,
+	},
+};
+
+WL_EXPORT const struct pixel_format_info *
+pixel_format_get_info(uint32_t format)
+{
+	unsigned int i;
+
+	for (i = 0; i < ARRAY_LENGTH(pixel_format_table); i++) {
+		if (pixel_format_table[i].format == format)
+			return &pixel_format_table[i];
+	}
+
+	return NULL;
+}
+
+WL_EXPORT unsigned int
+pixel_format_get_plane_count(const struct pixel_format_info *info)
+{
+	return info->num_planes ? info->num_planes : 1;
+}
+
+WL_EXPORT bool
+pixel_format_is_opaque(const struct pixel_format_info *info)
+{
+	return !info->opaque_substitute;
+}
+
+WL_EXPORT const struct pixel_format_info *
+pixel_format_get_opaque_substitute(const struct pixel_format_info *info)
+{
+	if (!info->opaque_substitute)
+		return info;
+	else
+		return pixel_format_get_info(info->opaque_substitute);
+}
+
+WL_EXPORT unsigned int
+pixel_format_width_for_plane(const struct pixel_format_info *info,
+			     unsigned int plane,
+			     unsigned int width)
+{
+	/* We don't support any formats where the first plane is subsampled. */
+	if (plane == 0 || !info->hsub)
+		return width;
+
+	return width / info->hsub;
+}
+
+WL_EXPORT unsigned int
+pixel_format_height_for_plane(const struct pixel_format_info *info,
+			      unsigned int plane,
+			      unsigned int height)
+{
+	/* We don't support any formats where the first plane is subsampled. */
+	if (plane == 0 || !info->vsub)
+		return height;
+
+	return height / info->vsub;
+}