lg_background.c File Reference

Functions
int	lg_draw_bg (int mode, int param_x, int param_y, const char *path)
void	lg_clear_bg (uint8_t red, uint8_t green, uint8_t blue)
void	lg_clear_bg_full (uint8_t red, uint8_t green, uint8_t blue, uint8_t alpha, GLbitfield mask)
void	lg_bg_info ()
int	lg_read_and_render_screen_back ()

Detailed Description

 === Draw background, and these sorts of things ===

Function Documentation

lg_draw_bg()

int lg_draw_bg	(	int	mode,
		int	param_x,
		int	param_y,
		const char *	path
	)

Draw (full or windowed) background - load (once) or draw or free

=== ONLY ONE INSTANCE at a time ===

Should be able to handle, at least, TWO INSTANCES -> bg = lg_bg_new(), lg_bg_draw(), ...

• if mode == LG_NEW, scale_x/y = param_x/y
• if mode == LG_ON, shift_x/y = param_x/y

Would be convenient to be able to zoom in LG_ON mode

Parameters

mode	LG_NEW or LG_ON
param_x	See above
param_y	See above
path	Path to image file

Returns

LG_OK if OK, LG_ERROR otherwise

lg_clear_bg()

void lg_clear_bg	(	uint8_t	red,
		uint8_t	green,
		uint8_t	blue
	)

Clear/paint with glClear(GL_COLOR_BUFFER_BIT) the viewport with colors - alpha = 255

NOTE: if followed by lg_swap_fb() without delay, and if a complete swap is needed, you may want to use glFinish() afterwards

Parameters

red
green
blue

lg_clear_bg_full()

void lg_clear_bg_full	(	uint8_t	red,
		uint8_t	green,
		uint8_t	blue,
		uint8_t	alpha,
		GLbitfield	mask
	)

glClear() everything then clear/paint the viewport with colors and mask

NOTE: if followed by lg_swap_fb() without delay, and if a complete swap is needed, you may want to use glFinish() afterwards

GLbitfield is 32-bit

Parameters

red
green
blue
alpha
mask	Bitwise OR of GL_COLOR_BUFFER_BIT, GL_DEPTH_BUFFER_BIT, GL_STENCIL_BUFFER_BIT

lg_bg_info()

void lg_bg_info

(

)

Print out background texture info, if set and valid

lg_read_and_render_screen_back()

int lg_read_and_render_screen_back

(

)

(Self-explanatory enough)

Returns

LG_OK if OK, LG_ERROR otherwise