Rendering
Functions for drawing text, shapes, images, gradients, and other visual elements.
render.create_font
Signature: render.create_font(font_path_or_name, size)
Description: Creates a font from a file path or system font name with the specified size.
If a file path (e.g. "verdana.ttf") is provided, it loads directly. If only a name is provided (e.g. "Verdana"), it will try to load from C:/Windows/Fonts/.
Parameters:
font_path_or_name (string): Path to a
.ttffont file or a system-installed font name.size (number): The font size in points.
Returns:
handle: A font handle to be used with
render.draw_text().
Example:
-- Create Verdana font from file
local font1 = render.create_font("verdana.ttf", 25)
-- Create Arial font from system fonts
local font2 = render.create_font("Arial", 20)
-- Draw text using created fonts
render.draw_text(font1, "Text from file font", 100, 100, 255, 255, 255, 255)
render.draw_text(font2, "Text from system font", 100, 150, 0, 255, 0, 255)render.create_font_from_buffer
Signature: render.create_font_from_buffer(label, size, buffer_handle)
Description: Creates a font from a memory buffer. Buffer must be allocated using m.alloc.
Parameters:
label (string): Label/name for the font.
size (number): The font size in points.
buffer_handle (handle): Buffer handle containing font data.
Returns:
handle: A font handle to be used with
render.draw_text().
Example:
-- Assume buffer is allocated with font data
local font = render.create_font_from_buffer("Verdana", 25, buffer_handle)
-- Draw text
render.draw_text(font, "Buffered font text", 200, 200, 255, 255, 0, 255)render.get_viewport_size
Signature: render.get_viewport_size()
Description: Retrieves the current screen/viewport dimensions.
Parameters: None
Returns:
width (number): The width of the viewport in pixels.
height (number): The height of the viewport in pixels.
Example:
-- Get screen dimensions
local screen_w, screen_h = render.get_viewport_size()
engine.log("Viewport size: " .. screen_w .. "x" .. screen_h, 255, 255, 255, 255)render.measure_text
Signature: render.measure_text(font_handle, text)
Description: Measures the width and height of text using the given font.
Parameters:
font_handle (handle): Font handle created with
render.create_font()orrender.create_font_from_buffer().text (string): The text to measure.
Returns:
width (number): Width of the text in pixels.
height (number): Height of the text in pixels.
Example:
local font = render.create_font("verdana.ttf", 25)
local w, h = render.measure_text(font, "Measure me!")
render.draw_rectangle(100, 100, w, h, 0, 255, 0, 128, 1, true)
render.draw_text(font, "Measure me!", 100, 100, 255, 255, 255, 255)render.draw_line
Signature: render.draw_line(x1, y1, x2, y2, r, g, b, a, thickness)
Description: Draws a line between two points with the specified color and thickness.
Parameters:
x1 (number): X-coordinate of the starting point.
y1 (number): Y-coordinate of the starting point.
x2 (number): X-coordinate of the ending point.
y2 (number): Y-coordinate of the ending point.
r (number): Red color component (0-255).
g (number): Green color component (0-255).
b (number): Blue color component (0-255).
a (number): Alpha (transparency) component (0-255).
thickness (number): Line thickness in pixels.
Returns: None
Example:
-- White diagonal line
render.draw_line(500, 500, 600, 600, 255, 255, 255, 255, 5)render.draw_rectangle
Signature: render.draw_rectangle(x, y, width, height, r, g, b, a, thickness, filled, rounding)
Description: Draws a rectangle with optional fill and rounding.
Parameters:
x (number): X-coordinate of the top-left corner.
y (number): Y-coordinate of the top-left corner.
width (number): Width of the rectangle in pixels.
height (number): Height of the rectangle in pixels.
r (number): Red color component (0-255).
g (number): Green color component (0-255).
b (number): Blue color component (0-255).
a (number): Alpha (transparency) component (0-255).
thickness (number): Border thickness in pixels (ignored if filled is true).
filled (boolean): Whether to draw a filled rectangle (true) or just the outline (false).
rounding (number): Corner rounding radius in pixels.
Returns: None
Example:
-- Filled yellow rectangle
render.draw_rectangle(700, 700, 50, 50, 255, 255, 0, 255, 1, true)
-- Outlined red rectangle with rounded corners
render.draw_rectangle(300, 300, 100, 50, 255, 0, 0, 255, 2, false, 6)render.draw_circle
Signature: render.draw_circle(x, y, radius, r, g, b, a, thickness, filled)
Description: Draws a circle with fill or outline.
Parameters:
x (number): X-coordinate of the center.
y (number): Y-coordinate of the center.
radius (number): Radius in pixels.
r (number): Red color component (0-255).
g (number): Green color component (0-255).
b (number): Blue color component (0-255).
a (number): Alpha (transparency) component (0-255).
thickness (number): Border thickness in pixels (ignored if filled is true).
filled (boolean): Whether to draw a filled circle (true) or just the outline (false).
Returns: None
Example:
-- Filled red circle
render.draw_circle(900, 900, 25, 255, 0, 0, 255, 5, true)render.draw_text
Signature: render.draw_text(font, text, x, y, r, g, b, a, outline_thickness, o_r, o_g, o_b, o_a)
Description: Draws text at position with optional outline.
Parameters:
font (handle): Font handle created with
render.create_font()orrender.create_font_from_buffer().text (string): The text to draw.
x (number): X-coordinate of the text position.
y (number): Y-coordinate of the text position.
r (number): Red color component (0-255).
g (number): Green color component (0-255).
b (number): Blue color component (0-255).
a (number): Alpha (transparency) component (0-255).
outline_thickness (number, optional): Thickness of the text outline (0 for no outline).
o_r (number, optional): Red color component for the outline (0-255).
o_g (number, optional): Green color component for the outline (0-255).
o_b (number, optional): Blue color component for the outline (0-255).
o_a (number, optional): Alpha component for the outline (0-255).
Returns: None
Example:
local font = render.create_font("verdana.ttf", 25)
-- Magenta with white outline
render.draw_text(font, "Test", 1000, 1000, 255, 0, 255, 255, 5, 255, 255, 255, 255)render.draw_triangle
Signature: render.draw_triangle(x1, y1, x2, y2, x3, y3, r, g, b, a, thickness, filled)
Description: Draws a triangle connecting three points.
Parameters:
x1, y1 (number): Coordinates of the first point.
x2, y2 (number): Coordinates of the second point.
x3, y3 (number): Coordinates of the third point.
r (number): Red color component (0-255).
g (number): Green color component (0-255).
b (number): Blue color component (0-255).
a (number): Alpha (transparency) component (0-255).
thickness (number): Border thickness in pixels (ignored if filled is true).
filled (boolean): Whether to draw a filled triangle (true) or just the outline (false).
Returns: None
Example:
-- Red triangle outline
render.draw_triangle(775, 825, 825, 825, 800, 775, 255, 0, 0, 255, 1, false)render.get_fps
Signature: render.get_fps()
Description: Gets the current overlay FPS.
Parameters: None
Returns:
fps (number): The current frames per second.
Example:
local fps = render.get_fps()
engine.log("FPS: " .. fps, 255, 255, 255, 255)render.create_bitmap_from_url
Signature: render.create_bitmap_from_url(url)
Description: Creates a bitmap from a URL.
Parameters:
url (string): The URL of the image to load.
Returns:
bitmap_handle: A handle to the created bitmap for use with rendering functions.
Example:
-- Create a bitmap from a URL
local bmp = render.create_bitmap_from_url("https://example.com/image.png")render.create_bitmap_from_buffer
Signature: render.create_bitmap_from_buffer(buffer_handle)
Description: Creates a bitmap from a memory buffer handle.
Parameters:
buffer_handle (handle): Buffer handle containing image data.
Returns:
bitmap_handle: A handle to the created bitmap for use with rendering functions.
Example:
-- Given a buffer handle with image bytes
local bmp = render.create_bitmap_from_buffer(buffer_handle)render.create_bitmap_from_file
Signature: render.create_bitmap_from_file(file_name)
Description: Creates a bitmap from a local file.
Parameters:
file_name (string): Path to the image file.
Returns:
bitmap_handle: A handle to the created bitmap for use with rendering functions.
Example:
local bmp = render.create_bitmap_from_file("images/logo.png")render.clip_start
Signature: render.clip_start(x, y, width, height)
Description: Begins a clipping region. All subsequent rendering will be restricted to this rectangle until render.clip_end() is called.
Parameters:
x (number): X-coordinate of the clipping region's top-left corner.
y (number): Y-coordinate of the clipping region's top-left corner.
width (number): Width of the clipping region in pixels.
height (number): Height of the clipping region in pixels.
Returns: None
Example:
render.clip_start(100, 100, 300, 200)
-- draw clipped content here
render.clip_end()render.clip_end
Signature: render.clip_end()
Description: Ends the active clipping region started by render.clip_start. Restores rendering output to the entire screen or parent context.
Parameters: None
Returns: None
Example:
-- Typically paired with clip_start; see that example.
render.clip_end()render.draw_four_corner_gradient
Signature: render.draw_four_corner_gradient(x, y, width, height, r1, g1, b1, r2, g2, b2, r3, g3, b3, r4, g4, b4)
Description: Draws a rectangle filled with a four-corner gradient. Each corner has its own RGB color value (top-left, top-right, bottom-left, bottom-right), blended smoothly across the area.
Parameters:
x (number): X-coordinate of the top-left corner.
y (number): Y-coordinate of the top-left corner.
width (number): Width of the rectangle in pixels.
height (number): Height of the rectangle in pixels.
r1, g1, b1 (number): RGB color components for the top-left corner (0-255).
r2, g2, b2 (number): RGB color components for the top-right corner (0-255).
r3, g3, b3 (number): RGB color components for the bottom-left corner (0-255).
r4, g4, b4 (number): RGB color components for the bottom-right corner (0-255).
Returns: None
Example:
render.draw_four_corner_gradient(
100, 100, 300, 200,
255, 0, 0, -- top-left red
0, 255, 0, -- top-right green
0, 0, 255, -- bottom-left blue
255, 255, 0 -- bottom-right yellow
)render.draw_polygon
Signature: render.draw_polygon(points_table, r, g, b, a, thickness, filled)
Description: Draws a polygon from a list of {x, y} points.
Parameters:
points_table (table): Array of points, each as
{x, y}(minimum 3 points).r (number): Red color component (0-255).
g (number): Green color component (0-255).
b (number): Blue color component (0-255).
a (number): Alpha (transparency) component (0-255).
thickness (number): Border thickness in pixels (ignored if filled is true).
filled (boolean): Whether to draw a filled polygon (true) or just the outline (false).
Returns: None
Example:
local points = { {100,100}, {200,150}, {150,250}, {50,200} }
render.draw_polygon(points, 0, 255, 255, 255, 2, true)render.draw_ellipse
Signature: render.draw_ellipse(x, y, rx, ry, r, g, b, a, thickness, filled)
Description: Draws an ellipse.
Parameters:
x (number): X-coordinate of the center.
y (number): Y-coordinate of the center.
rx (number): Radius along the X axis in pixels.
ry (number): Radius along the Y axis in pixels.
r (number): Red color component (0-255).
g (number): Green color component (0-255).
b (number): Blue color component (0-255).
a (number): Alpha (transparency) component (0-255).
thickness (number): Border thickness in pixels (ignored if filled is true).
filled (boolean): Whether to draw a filled ellipse (true) or just the outline (false).
Returns: None
Example:
-- Cyan outlined ellipse
render.draw_ellipse(400, 300, 120, 80, 0, 255, 255, 255, 2, false)render.draw_arc
Signature: render.draw_arc(x, y, rx, ry, start_angle, sweep_angle, r, g, b, a, thickness, filled)
Description: Draws an arc or pie slice.
Parameters:
x (number): X-coordinate of the center.
y (number): Y-coordinate of the center.
rx (number): Radius along the X axis in pixels.
ry (number): Radius along the Y axis in pixels.
start_angle (number): Starting angle in degrees.
sweep_angle (number): Angle span in degrees (positive = clockwise or implementation-defined).
r (number): Red color component (0-255).
g (number): Green color component (0-255).
b (number): Blue color component (0-255).
a (number): Alpha (transparency) component (0-255).
thickness (number): Border thickness in pixels (ignored if filled is true).
filled (boolean): Whether to draw a filled pie slice (true) or just the arc outline (false).
Returns: None
Example:
-- 90-degree pie slice
render.draw_arc(500, 400, 60, 60, 0, 90, 255, 128, 0, 255, 1, true)render.draw_gradient_line
Signature: render.draw_gradient_line(x1, y1, x2, y2, color_table, thickness)
Description: Draws a line with gradient colors from start to end.
Parameters:
x1 (number): X-coordinate of the starting point.
y1 (number): Y-coordinate of the starting point.
x2 (number): X-coordinate of the ending point.
y2 (number): Y-coordinate of the ending point.
color_table (table): List of colors, each as
{r, g, b, a}. Provide at least two entries (start and end).thickness (number): Line thickness in pixels.
Returns: None
Example:
-- Gradient from red to blue
render.draw_gradient_line(100, 200, 400, 200, { {255,0,0,255}, {0,0,255,255} }, 3)render.draw_gradient_rectangle
Signature: render.draw_gradient_rectangle(x, y, width, height, color_table, rounding)
Description: Draws a rectangle with gradient fill.
Parameters:
x (number): X-coordinate of the top-left corner.
y (number): Y-coordinate of the top-left corner.
width (number): Width of the rectangle in pixels.
height (number): Height of the rectangle in pixels.
color_table (table): List of colors, each as
{r, g, b, a}. Typically two entries for a linear gradient.rounding (number, optional): Corner rounding radius in pixels.
Returns: None
Example:
-- Vertical gradient yellow to magenta with rounded corners
render.draw_gradient_rectangle(200, 250, 180, 100, { {255,255,0,255}, {255,0,255,255} }, 8)Example Usage
-- Create a font for rendering text
local font_handle = render.create_font("verdana.ttf", 25)
-- Callback function for rendering
function enginetick_callback()
-- Draw a white diagonal line
render.draw_line(500, 500, 600, 600, 255, 255, 255, 255, 5)
-- Draw a filled yellow rectangle
render.draw_rectangle(700, 700, 50, 50, 255, 255, 0, 255, 1, true)
-- Draw a filled red circle
render.draw_circle(900, 900, 25, 255, 0, 0, 255, 5, true)
-- Draw text in magenta
render.draw_text(font_handle, "Test", 1000, 1000, 255, 0, 255, 255, 5, 255, 0, 0, 0)
-- Draw a red triangle
render.draw_triangle(775, 825, 825, 825, 800, 775, 255, 0, 0, 255, 1, false)
end
engine.register_on_engine_tick(enginetick_callback)Last updated
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