Vector path structures

This section provides an overview of vector path structures.

vg_lite_hw_memory structure

This structure gets the memory allocation information recorded by the kernel.

Used in structure: vg_lite_path_t.

vg_lite_hw_memory_t member	Type	Description
handle	vg_lite_pointer	GPU memory object handle
memory	vg_lite_pointer	Logical memory address
address	vg_lite_uint32_t	GPU memory address
bytes	vg_lite_uint32_t	Size of memory
property	vg_lite_uint32_t	Bit 0 is used for path upload: - 0: Disable path data uploading (always embedded into command buffer) - 1: Enable auto path data uploading

Parent topic:Vector path structures

vg_lite_path_t structure

This structure describes VGLite path data.

Path data is made of op codes and coordinates. The format for op codes is always VG_LITE_S8. For more details on opcodes, see Vector path opcodes for plotting paths.

Used in init functions: vg_lite_init_path, vg_lite_init_arc_path, vg_lite_upload_path, vg_lite_clear_path, vg_lite_append_path.

Used in draw functions: vg_lite_draw, vg_lite_draw_grad, vg_lite_draw_radial_grad, vg_lite_draw_pattern.

vg_lite_path_t members	Type	Description
bounding_box[4]	vg_lite_float_t	bounding box for path [0] left [1] top [2] right [3] bottom
quality	vg_lite_quality_t	enum for quality hint for the path, anti-aliasing level
format	vg_lite_format_t	enum for coordinate format
uploaded	vg_lite_hw_memory_t	struct with path data that has been uploaded into GPU addressable memory
path_length	vg_lite_uint32_t	number of bytes in the path
path	vg_lite_pointer	pointer to path data
path_changed	vg_lite_int8_t	0: not changed; 1: changed.
pdata_internal	vg_lite_int8_t	0: path data memory is allocated by application; 1: path data memory is allocated by driver.
path_type	vg_lite_path_type_t	The draw path type as specified in enum vg_lite_path_type_t. (added for stroke control, from March 2022)
*stroke	vg_lite_stroke_t	As defined by structure vg_lite_stroke_t (added for stroke control, from March 2022)
stroke_path	vg_lite_pointer	Pointer to the physical description of the stroke path. (added for stroke control, from March 2022)
stroke_size	vg_lite_uint32_t	Number of bytes in the stroke path data. (added for stroke control, from March 2022)
stroke_color	vg_lite_color_t	The stroke path fill color. (from Sept 2022)
add_end	vg_lite_int8_t	Flag that add end_path in driver (from March 2023)

Special notes for path objects:

• Endianness has no impact, as it is aligned against the boundaries

• Multiple contiguous opcodes should be packed by the size of the specified data format. For example, by 2 bytes for VG_LITE_S16 or by 4 bytes for VG_LITE_S32.

For example, because opcodes are 8-bit (1-byte), 16-bit (2-byte), or 32-bit (4-byte) data types:

…
<opcode1_that_needs_data>
<align_to_data_size>
<data_for_opcode1>
<opcode2_that_doesnt_need_data>
<align_to_data_size>
<opcode3_that_needs_data>
<align_to_data_size>
<data_for_opcode3>
…

• Path data in the array should always be 1-, 2-, or 4-byte aligned, depending on the format:

For example, for 32-bit (4-byte) data types:

…
<opcode1_that_needs_data>
<pad to 4 bytes>
<4 byte data_for_opcode1>
<opcode2_that_doesnt_need_data>
<pad to 4 bytes>
<opcode3_that_needs_data>
<pad to 4 bytes>
<4 byte data_for_opcode3>
…

Parent topic:Vector path structures

Parent topic:Vector path control