API.md

SDL 77 API Documentation

Functions

INTEGER FUNCTION GKEY(ICODE)

Returns 1 if key of given key code has been pressed, else 0.

INTEGER*8 FUNCTION GTICKS()

Returns number of milliseconds since the SDL library initialisation as 8-byte integer.

INTEGER*8 FUNCTION GTIME()

Returns UNIX timestamp as 8-byte integer.

Subroutines

SUBROUTINE GALLOC(ISTAT)

Returns allocation status of current layer. The status is 1 if the layer is allocated, else 0.

SUBROUTINE GBLIT(I, IX1, IY1, IX2, IY2, IW, IH)

Blits rectangle copied from source layer I to target layer selected with GLAYER().

SUBROUTINE GCIRC(IX, IY, IR)

Draws circle in current colour at IX, IY, and of radius IR.

SUBROUTINE GCLOSE()

Cleans up and quits SDL 1.2.

SUBROUTINE GCOLOR(IR, IG, IB)

Sets current colour in RGB.

SUBROUTINE GCOLK(IR, IG, IB)

Sets colour key (transparent colour) in current layer. Not necessary for images with alpha channels that have been loaded with SDL_image.

SUBROUTINE GCPPAL(I, IX, IY)

Copies palette colour I to current layer surface. The surface has to be locked beforehand with GLOCK().

SUBROUTINE GCPPIX(I, IX1, IY1, IX2, IY2)

Copies pixel from given layer I to target layer selected with GLAYER(). The target layer has to be locked beforehand with GLOCK().

SUBROUTINE GCREAT(IW, IH)

Creates a new layer selected with GLAYER() of given size. Replaces existing layer. The default background colour is black.

SUBROUTINE GCUR(ITOGGLE)

Shows or hides the mouse cursor, depending on ITOGGLE (0 or 1).

SUBROUTINE GDELAY(IDELAY)

Delays program execution for given time in msec.

SUBROUTINE GEVENT(IEVENT, ISTAT)

Polls an SDL event. The event type is returned in IEVENT, the status in ISTAT. If ISTAT is 1, another event is waiting.

SUBROUTINE GFILL()

Fills current layer in global colour.

SUBROUTINE GFILLR(IX, IY, IW, IH)

Fills rectangle of given size in global colour.

SUBROUTINE GFLUSH()

Flips screen surface.

SUBROUTINE GGRAB(ITOGGLE)

Grabs mouse and keyboard input if ITOGGLE is 1.

SUBROUTINE GHLINE(IX1, IX2, IY)

Draws horizontal line to layer surface. No bounds checking!

SUBROUTINE GLAYER(LAYER)

Selects layer by index. The screen layer is alway 0. Up to 7 additional layers can be created, either as buffer or to store images loaded from file.

SUBROUTINE GLINE(IX1, IY1, IX2, IY2)

Draws a line from IX1, IY1 to IX2, IY2.

SUBROUTINE GLOAD(FILE, ISTAT)

Loads image from file to current layer, using SDL or SDL_image (if available). FILE is the null-terminated path to the image file. ISTAT is set to 0 if the image has been loaded successfully.

SUBROUTINE GLOCK()

Locks current layer for direct pixel manipulation.

SUBROUTINE GMBUT(IBUT1, IBUT2, IBUT3)

Returns mouse button clicks (left, middle, right). On click, the button state is set to 1.

SUBROUTINE GMOUSE(IXREL, IXREL, IX, IY)

Returns relative mouse motion and absolute mouse position as 8-byte integer.

SUBROUTINE GOPEN(IW, IH, TITLE, ISTAT)

Opens the SDL 1.2 window. Only a single window can be opened at a time. TITLE is the null-terminated window title. ISTAT is set to 0 if the window was opened successfully.

SUBROUTINE GPAL(N)

Allocates palette memory for N colours.

SUBROUTINE GPIXEL(IX, IY)

Draws single pixel on layer. The surface must be locked.

SUBROUTINE GSETP(I, IR, IG, IB)

Sets RGB palette colour at index I in screen format to given RGB values.

SUBROUTINE GSSHOT(FILE)

Copies screen surface in BMP format to given file (screen shot). The file path must be null-terminated.

SUBROUTINE GULOCK()

Unlocks layer surface.

SUBROUTINE GVIDEO(IHW, IWM, IVM)

Returns status information (hardware acceleration, window manager, video memory).

SUBROUTINE GVLINE(IX, IY1, IY2)

Draws vertical line to layer surface. No bounds checking!

SUBROUTINE GWARP(IX, IY)

Warps mouse to IX, IY.

SUBROUTINE MCHAN(I, ICHAN, LOOPS)

Plays sound effect I in chunk array on channel ICHAN. Set the channel to -1 to use the next free. LOOPS sets the number of loops to play for.

SUBROUTINE MCLOSE()

Closes music file.

SUBROUTINE MHALT()

Stops music playback.

SUBROUTINE MLOAD(FILE, ISTAT)

Loads music file (preferable, in OGG format). ISTAT is set to 0 if the file has been loaded successfully.

SUBROUTINE MLOADW(I, FILE, ISTAT)

Loads WAV file to position I in audio chunk array. Up to eight sound effects may be loaded (from 0 to 7). ISTAT is set to 0 if the file has been loaded successfully.

SUBROUTINE MPAUSE()

Pauses music playback.

SUBROUTINE MPLAY(LOOPS)

Plays music file. LOOPS sets the number of loops to play for, 0 means “play once and stop”.