Graphics

This section provides APIs to display images and basic shapes, such as points, lines, rectangles, circles and polygons. More...

Overview

This section provides APIs to display images and basic shapes, such as points, lines, rectangles, circles and polygons.

Only BMP image is supported in SDK.

Terms and Acronyms

Terms	Details
GDI	Graphics Device Interface. For more information, please refer to Wikipedia.
RGB	An additive color model in which red, green and blue light are added together in various ways to reproduce a broad array of colors. For more information, please refer to Wikipedia.
BLT	Bit block transfer, is a data operation commonly used in computer graphics in which several bitmaps are combined into one using a Boolean function. For more information, please refer to Wikipedia.

How to use this module

• Step 1: Initialize the GDI.
  • Sample Code:

    #define LCD_WITH   (240)
    #define LCD_HEIGHT (240)
    static uint8_t layer_buffer[LCD_WIDTH * LCD_HEIGHT * 2];
    gdi_init(LCD_WIDTH, LCD_HEIGHT, GDI_COLOR_FORMAT_16, layer_buffer);

• Step 2: Use GDI APIs to draw. To display an image, please use the resource generator tool to add image resource with image_id and run this tool to populate raw image data. For resource generator tool usage, please navigate to ".\tools\mtk\Resgen\" in Windows command window and type in "make ?".
  • Sample code:

    gdi_draw_filled_rectangle(0, 0, LCD_WIDTH, LCD_HEIGHT, gdi_get_color_from_argb(0, 0, 0, 0)); // Clear the screen to black.
    gdi_draw_rectangle(50, 50, 100, 100, gdi_get_color_from_argb(0, 255, 0, 0)); // Draw a red rectangle.
    gdi_image_draw_by_id(10, 10, image_id);

• Step 3: Update the screen.
  • Sample code:

    gdi_lcd_update_screen(0, 0, LCD_WITH, LCD_HEIGHT);

Functions
void	gdi_init (uint32_t width, uint32_t height, gdi_color_format_t color_format, uint8_t *buffer)
	This function initializes the GDI. More...
gdi_color_t	gdi_get_color_from_argb (uint8_t alpha, uint8_t red, uint8_t green, uint8_t blue)
	This function generates a color from given alpha, red, green, blue. More...
void	gdi_get_argb_from_color (uint8_t *alpha, uint8_t *red, uint8_t *green, uint8_t *blue, gdi_color_t color)
	This function extracts alpha, red, green, blue from the given color, the value range of the component is relative with the color format. More...
void	gdi_draw_point (int32_t x, int32_t y, gdi_color_t color)
	This function draws a point on the screen. More...
void	gdi_draw_line (int32_t x1, int32_t y1, int32_t x2, int32_t y2, gdi_color_t color)
	This function draws a line on the screen. More...
void	gdi_draw_rectangle (int32_t x1, int32_t y1, int32_t x2, int32_t y2, gdi_color_t color)
	This function draws a rectangle on the screen. More...
void	gdi_draw_filled_rectangle (int32_t x1, int32_t y1, int32_t x2, int32_t y2, gdi_color_t color)
	This function draws a solid rectangle on the screen. More...
void	gdi_draw_circle (int32_t x, int32_t y, int32_t radius, gdi_color_t color)
	This function draws a circle on the screen. More...
void	gdi_draw_filled_circle (int32_t x, int32_t y, int32_t radius, gdi_color_t color)
	This function draws a solid circle on the screen. More...
void	gdi_draw_filled_polygon (gdi_point_t point[], uint32_t point_num, gdi_color_t color)
	This function draws a solid polygon on current screen. More...
void	gdi_draw_polygon (gdi_point_t point[], uint32_t point_num, gdi_color_t color)
	This function draws a polygon on current screen. More...
gdi_result_t	gdi_image_draw_by_id (int32_t x, int32_t y, uint16_t image_id)
	This function draws an image from a resource with original image dimension. More...
gdi_result_t	gdi_image_draw_resized_by_id (int32_t x, int32_t y, uint32_t width, uint32_t height, uint16_t image_id)
	This function draws an image from a resource with specified dimensions. More...
gdi_result_t	gdi_image_get_dimension_by_id (uint16_t image_id, uint32_t *width, uint32_t *height)
	This function gets the image dimension by the image resource ID. More...
gdi_result_t	gdi_lcd_update_screen (uint32_t x1, uint32_t y1, uint32_t x2, uint32_t y2)
	This function updates the LCD screen. More...

Modules
	Define
	This section defines macros for the GDI.
	Struct
	Basic data structure for the GDI.

Function Documentation

void gdi_draw_circle	(	int32_t	x,
		int32_t	y,
		int32_t	radius,
		gdi_color_t	color
	)

This function draws a circle on the screen.

Parameters

[in]	x	is the x position of the center of the circle.
[in]	y	is the y position of the center of the circle.
[in]	radius	is the radius of the circle.
[in]	color	is the color of the circle.

Returns

void.

void gdi_draw_filled_circle	(	int32_t	x,
		int32_t	y,
		int32_t	radius,
		gdi_color_t	color
	)

This function draws a solid circle on the screen.

Parameters

[in]	x	is the x position of the center of the circle.
[in]	y	is the y position of the center of the circle.
[in]	radius	is the radius of the circle.
[in]	color	is the color to fill the circle.

Returns

void.

void gdi_draw_filled_polygon	(	gdi_point_t	point[],
		uint32_t	point_num,
		gdi_color_t	color
	)

This function draws a solid polygon on current screen.

Parameters

[in]	point	is the point array.
[in]	point_num	is the number of elements of the point array.
[in]	color	is the color to fill the polygon.

Returns

void.

void gdi_draw_filled_rectangle	(	int32_t	x1,
		int32_t	y1,
		int32_t	x2,
		int32_t	y2,
		gdi_color_t	color
	)

This function draws a solid rectangle on the screen.

Parameters

[in]	x1	is the x position of the left-top corner of rectangle.
[in]	y1	is the y position of the left-top corner of rectangle.
[in]	x2	is the x position of the right-down corner of rectangle.
[in]	y2	is the y position of the right-down corner of rectangle.
[in]	color	is the color to fill the rectangle.

Returns

void.

void gdi_draw_line	(	int32_t	x1,
		int32_t	y1,
		int32_t	x2,
		int32_t	y2,
		gdi_color_t	color
	)

This function draws a line on the screen.

Parameters

[in]	x1	is the x position of the first end point of line.
[in]	y1	is the y position of the first end point of line.
[in]	x2	is the x position of the other end point of line.
[in]	y2	is the y position of the other end point of line.
[in]	color	is the color of the line.

Returns

void.

void gdi_draw_point	(	int32_t	x,
		int32_t	y,
		gdi_color_t	color
	)

This function draws a point on the screen.

Parameters

[in]	x	is the x position of the point.
[in]	y	is the y position of the point.
[in]	color	is the color of the point.

Returns

void.

void gdi_draw_polygon	(	gdi_point_t	point[],
		uint32_t	point_num,
		gdi_color_t	color
	)

This function draws a polygon on current screen.

Parameters

[in]	point	is the point array.
[in]	point_num	is the number of elements of the point array.
[in]	color	is the color of polygon.

Returns

void.

void gdi_draw_rectangle	(	int32_t	x1,
		int32_t	y1,
		int32_t	x2,
		int32_t	y2,
		gdi_color_t	color
	)

This function draws a rectangle on the screen.

Parameters

[in]	x1	is the x position of the left-top corner of rectangle.
[in]	y1	is the y position of the left-top corner of rectangle.
[in]	x2	is the x position of the right-down corner of rectangle.
[in]	y2	is the y position of the right-down corner of rectangle.
[in]	color	is the color of the rectangle frame.

Returns

void.

void gdi_get_argb_from_color	(	uint8_t *	alpha,
		uint8_t *	red,
		uint8_t *	green,
		uint8_t *	blue,
		gdi_color_t	color
	)

This function extracts alpha, red, green, blue from the given color, the value range of the component is relative with the color format.

Parameters

[out]	alpha	is the alpha component value of the given color.
[out]	red	is the red component value of the given color.
[out]	green	is the green component value of the given color.
[out]	blue	is the blue component value of the given color.
[in]	color	is the given color to extract alpha, red, green, blue.

Returns

void.

gdi_color_t gdi_get_color_from_argb	(	uint8_t	alpha,
		uint8_t	red,
		uint8_t	green,
		uint8_t	blue
	)

This function generates a color from given alpha, red, green, blue.

Parameters

[in]	alpha	is the alpha component value to generate the color.
[in]	red	is the red component value to generate the color.
[in]	green	is the green component value to generate the color.
[in]	blue	is the blue component value to generate the color.

Returns

the generated color.

gdi_result_t gdi_image_draw_by_id	(	int32_t	x,
		int32_t	y,
		uint16_t	image_id
	)

This function draws an image from a resource with original image dimension.

Parameters

[in]	x	is the x position to draw image.
[in]	y	is the y position to draw image.
[in]	image_id	is the image resource ID.

Returns

whether the operation is successful.

gdi_result_t gdi_image_draw_resized_by_id	(	int32_t	x,
		int32_t	y,
		uint32_t	width,
		uint32_t	height,
		uint16_t	image_id
	)

This function draws an image from a resource with specified dimensions.

Parameters

[in]	x	is the x position to draw image.
[in]	y	is the y position to draw image.
[in]	width	is the image width to draw.
[in]	height	is the image height to draw.
[in]	image_id	is the image resource ID.

Returns

whether the operation is successful.

gdi_result_t gdi_image_get_dimension_by_id	(	uint16_t	image_id,
		uint32_t *	width,
		uint32_t *	height
	)

This function gets the image dimension by the image resource ID.

Parameters

[in]	image_id	is the image resource ID.
[out]	width	is the image width.
[out]	height	is the image height.

Returns

whether the operation is successful.

void gdi_init	(	uint32_t	width,
		uint32_t	height,
		gdi_color_format_t	color_format,
		uint8_t *	buffer
	)

This function initializes the GDI.

Parameters

[in]	width	is the width of the LCD.
[in]	height	is the height of the LCD.
[in]	color_format	is the color format of the buffer.
[in]	buffer	is the buffer containing the drawing content.

Returns

void.

gdi_result_t gdi_lcd_update_screen	(	uint32_t	x1,
		uint32_t	y1,
		uint32_t	x2,
		uint32_t	y2
	)

This function updates the LCD screen.

The four parameters are the region to update the LCD screen.

Parameters

[in]	x1	is x of left-top corner of update region.
[in]	y1	is y of left-top corner of update region.
[in]	x2	is x of right-down corner of update region.
[in]	y2	is y of right-down corner of update region.

Returns

whether the operation is successful.