WowBot: Split C++ Native API into per-module pages with minimal examples (WowBot)

2026-07-26T09:47:45Z

Split C++ Native API into per-module pages with minimal examples (WowBot)

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{{notice|'''Official WOWCube SDK documentation.''' SDK 6.3, C++ (WebAssembly) API. Signatures are extracted from the canonical SDK headers shipped with the WOWCube Development Kit; the headers remain authoritative.}}

{{SDK 6.3 nav}}

''← [[SDK 6.3]] · [[SDK 6.3/C++/Native API|C++ Native API]] / Graphics''

Immediate-mode drawing on the module's displays: primitives, images, text, shaders, QR codes and render targets. (The retained alternative is the [[SDK 6.3/C++/GFX Engine|GFX Engine]].)

Shared types, enums and constants are listed on the [[SDK 6.3/C++/Native API#Types and data structures|Native API overview]].

== Minimal example ==

From the official ''HelloWOWCube'' project — direct drawing in <code>on_Render</code>:

for(auto it = screens.begin(); it != screens.end(); ++it)
{
GFX_setRenderTarget(it->ID());
GFX_clear(Colors::black);
GFX_drawText(120, 100, TEXT_SIZE, 0, text_align_t::TEXT_ALIGN_CENTER, Colors::white, "HELLO");
GFX_render();
}

== Functions ==

===GFX_getAssetId===
Syntax:
i32_t GFX_getAssetId(const char* spriteName)

Description:
: Get an image ID by the filename.
: Usually an application uses image IDs to draw sprites and backgrounds. But
: sometimes IDs are unknown, e.g. in common libraries, or they change rapidly
: during development. This interface can be used to get an ID of the image by
: its filename in the runtime. Maximum asset name length is 15 characters,
: remaining symbols are truncated during lookup.

Return values:
: The ID of image with a given filename or -1 in case of error.

History:
: v5.0 - renamed from GFX_getId() to GFX_getAssetId()
: v6.0 - truncate asset name in WASM API

===GFX_clear===
Syntax:
i32_t GFX_clear(u32_t color)

Description:
: Clear a layer with a given color.

History:
: v6.0 - changed color format

===GFX_drawText===
Syntax:
i32_t GFX_drawText(i32_t x, i32_t y, u32_t scale, u32_t angle, u32_t align, u32_t color, const char* text)

Description:
: Draw a formatted text by the specified coordinates with a given color,
: scale, text align and a rotation angle.

History:
: v5.0 - clarified documentation, added GFX_drawTextXY() alias

===GFX_drawPoint===
Syntax:
i32_t GFX_drawPoint(i32_t x, i32_t y, u32_t color)

Description:
: Draw a point specified by its coordinates with a given color.

History:
: v5.0 - added GFX_drawPointXY() alias

===GFX_drawCircle===
Syntax:
i32_t GFX_drawCircle(u32_t x, u32_t y, u32_t radius, u32_t width, u32_t color)

Description:
: Draw a circle at the given point with given radius, color and line width.

History:
: v5.0 - added GFX_drawCircleXY() alias

===GFX_drawSolidCircle===
:'''Deprecated.''' use fill shader intead
Syntax:
i32_t GFX_drawSolidCircle(u32_t x, u32_t y, u32_t radius, u32_t color)

Description:
: Draw a solid circle at the given point with given radius and color.

History:
: v5.0 - added GFX_drawSolidCircleXY() alias
: v6.0 - DEPRECATED, use GFX_setFillShader() instead

===GFX_drawArc===
Syntax:
i32_t GFX_drawArc(i32_t x, i32_t y, u32_t radius, u32_t width, u32_t angle0, u32_t angle1, u32_t color)

Description:
: Draw an arc at the given point with given radius, line width, color and
: angles.

History:
: v5.0 - added GFX_drawArcXY() alias

===GFX_drawSector===
Syntax:
i32_t GFX_drawSector(i32_t x, i32_t y, u32_t radius, u32_t angle0, u32_t angle1, u32_t color)

Description:
: Draw a filled circular sector, connecting the arc to the circle's center
: like a piece of pie.

History:
: v5.1 - created

===GFX_drawLine===
Syntax:
i32_t GFX_drawLine(i32_t x0, i32_t y0, i32_t x1, i32_t y1, u32_t thickness, u32_t color)

Description:
: Draw a line with from a given point to another one and given width and
: color.

History:
: v5.0 - added GFX_drawLineXY() alias

===GFX_drawRectangle===
Syntax:
i32_t GFX_drawRectangle(i32_t x, i32_t y, i32_t w, i32_t h, u32_t color)

Description:
: Draw a solid rectangle at a given position with specified dimensions and a
: color.

History:
: v5.0 - added GFX_drawRectangleXY() alias

===GFX_bakeImage===
Syntax:
i32_t GFX_bakeImage(spriteID_t id, u32_t width, u32_t height, GFX_PixelFormat_t format, u32_t overwrite)

Description:
: Set an ID of a memory buffer to save next rendering result.
: Specifies the image that will be created by combining the group of
: graphical primitives used between GFX_bakeImage() and GFS_render()
: according their order and taking into account alpha channel in images. HW
: has a limitation and can combine no more than 4 layers simultaneously, so
: if there are more primitives then they will be combined in a cascade.
: Useful for creating complex images like backgrounds for later usage.

History:
: v6.0 - added overwrite parameter

===GFX_setRenderTarget===
Syntax:
i32_t GFX_setRenderTarget(u32_t display)

Description:
: Set a screen which will be used to display next rendering result.
: Cube module is a special device which has 3 independent screens to display
: graphics. GFX_setRenderTarget() specifies a screen number which will be
: used to display a next rendering result. Graphics primitives used in
: between GFX_setRenderTarget() and GFX_render() calls will be combined
: together according their order and taking into account alpha channel in
: images. Resulting image will be immediately flushed onto the given screen.
: HW has a limitation and can combine no more than 4 layers simultaneously,
: so if there are more primitives then they will be combined in a cascade. To
: display anything on the screen GFX_setRenderTarget() has to be always
: called.

History:
: v5.0 - renamed from GFX_updateDisplay() to GFX_setRenderTarget()

===GFX_drawImage===
Syntax:
i32_t GFX_drawImage(spriteID_t id, i32_t x, i32_t y, u32_t opacity, u32_t colorKey, u32_t scale_x, u32_t scale_y, u32_t angle, u32_t mirror)

Description:
: Draw an image from application assets at a specified position and with
: given transformations.

History:
: v5.0 - added GFX_drawImageXY() alias, color argument clarified
: v6.0 - added scale parameters

===GFX_drawBakedImage===
Syntax:
i32_t GFX_drawBakedImage(i32_t x, i32_t y, u32_t opacity, u32_t colorKey, u32_t scale_x, u32_t scale_y, u32_t angle, u32_t mirror, spriteID_t id)

Description:
: Draw a previously baked image at a specified position and with given
: transformations.

History:
: v5.0 - added GFX_drawBakedImageXY() alias, color argument clarified
: v6.0 - added scale parameters

===GFX_drawQrCode===
Syntax:
i32_t GFX_drawQRCode(i32_t x, i32_t y, u32_t size, u32_t color0, u32_t color1, u32_t angle, u32_t id, const char *text)

Description:
: Generate and draw QR-code for a given text string.
: Supported version 2 which is limited by 32 characters of input.

History:
: v6.0 - added

===GFX_render===
Syntax:
i32_t GFX_render()

Description:
: Start rendering process.

===GFX_clearCache===
Syntax:
i32_t GFX_clearCache()

Description:
: Clear all cached images.
: Oldest accessed image cache will be automatically freed if there is not
: enough memory to cache a new image. This function forces this process, e.g.
: when switch game levels.

===GFX_removeBakedImage===
Syntax:
i32_t GFX_removeBakedImage(spriteID_t id)

Description:
: Remove specified baked image from cache.
: Baked images do not automatically invalidate. This function allows to
: remove any baked image from cache to save some space.

History:
: v6.0 - added

===GFX_cacheImages===
Syntax:
i32_t GFX_cacheImages(spriteID_t* spriteIDs, u32_t count)

Description:
: Force platform to cache application images.
: Platform automatically reads and caches images from flash when the
: application draws an image. Flash operations are synchronous and may cause
: delays especially when reading large portions of data. To prevent the
: application from lags it is possible to cache image data in advance.
: However if application requests to draw a non-cached image and there is not
: enough memory then oldest accessed images will be removed from cache. Also
: there is a limit of 256 for a total number of cached images.

Return values:
: Number of cached images or negative value if an error happened. Error
: codes:
: * -1 invalid function arguments count
: * -2 invalid imageList array

History:
: v5.0 - moved from appCtrl module to graphics

===GFX_setFpsWindow===
Syntax:
i32_t GFX_setFpsWindow(u32_t size)

Description:
: Set the averaging window (in frames) used by the on-screen FPS counter (see <code>Application::ShowFPSCounter()</code>).

===GFX_getAssetsCount===
Syntax:
i32_t GFX_getAssetsCount()

Description:
: Get the total count of graphic assets.

Return values:
: Number of graphic assets.

History:
: v6.0 - added

===GFX_setFillShader===
Syntax:
i32_t GFX_setFillShader(u32_t color)

Description:
: Fill next primitives with specified color.

History:
: v6.0 - added primitives shading

===GFX_setLinearGradientShader===
Syntax:
i32_t GFX_setLinearGradientShader(u32_t x0, u32_t y0, u32_t x1, u32_t y1, u32_t color0, u32_t color1)

Description:
: Fill next primitives with linear gradient from a given point / color to
: another one.

History:
: v6.0 - added primitives shading

===GFX_setRadialGradientShader===
Syntax:
i32_t GFX_setRadialGradientShader(u32_t x0, u32_t y0, u32_t radius, u32_t color0, u32_t color1)

Description:
: Fill next primitives with radial gradient from a given point with radius
: and from a given color to another one.

History:
: v6.0 - added primitives shading

===GFX_removeShader===
Syntax:
i32_t GFX_removeShader()

Description:
: Do not use shading in next primitives.

History:
: v6.0 - added primitives shading

===GFX_drawSubImage===
Syntax:
i32_t GFX_drawSubImage(spriteID_t id,i32_t x,i32_t y,u32_t rect_x,u32_t rect_y,u32_t rect_w,u32_t rect_h,u32_t opacity,u32_t colorKey,u32_t scale_x, u32_t scale_y,u32_t angle, u32_t mirror)

Description:
: Draw a sub window of an image from application assets at a specified
: position and with given transformations.

History:
: v6.2 - added

[[Category:SDK 6.3]]
[[Category:C++ API]]

SDK 6.3/C++/Graphics - Revision history

WowBot: Split C++ Native API into per-module pages with minimal examples (WowBot)