graph.c

#include <kernel.h>
#include <gs_privileged.h>
 
#include <graph.h>
 
int graph_initialize(int fbp, int width, int height, int psm, int x, int y)
{
 
    int mode = graph_get_region();
 
    // Set a default interlaced video mode with flicker filter.
    graph_set_mode(GRAPH_MODE_INTERLACED, mode, GRAPH_MODE_FIELD, GRAPH_ENABLE);
 
    // Set the screen up
    graph_set_screen(0,0,width,height);
 
    // Set black background
    graph_set_bgcolor(0,0,0);
 
    graph_set_framebuffer_filtered(fbp,width,psm,x,y);
 
    graph_enable_output();
 
    // End function.
    return 0;
 
}
 
int graph_add_vsync_handler(int (*vsync_callback)(int cause))
{
 
    int callback_id;
 
    DIntr();
 
    callback_id = AddIntcHandler(INTC_VBLANK_S, vsync_callback, -1);
 
    EnableIntc(INTC_VBLANK_S);
 
    EIntr();
 
    return callback_id;
 
}
 
void graph_remove_vsync_handler(int callback_id)
{
 
    DIntr();
 
    DisableIntc(INTC_VBLANK_S);
 
    RemoveIntcHandler(INTC_VBLANK_S, callback_id);
 
    EIntr();
 
}
 
int graph_get_field(void)
{
 
    // Return the currently displayed field.
    if (*GS_REG_CSR & (1 << 13))
    {
 
        return GRAPH_FIELD_ODD;
 
    }
 
    return GRAPH_FIELD_EVEN;
 
}
 
void graph_wait_hsync(void)
{
 
    // Initiate hsync interrupt
    *GS_REG_CSR |= *GS_REG_CSR & 4;
 
    // Wait for hsync interrupt to be generated.
    while (!(*GS_REG_CSR & 4));
 
}
 
int graph_check_vsync(void)
{
 
    return (*GS_REG_CSR & 8);
 
}
 
void graph_start_vsync(void)
{
 
    *GS_REG_CSR |= *GS_REG_CSR & 8;
 
}
 
void graph_wait_vsync(void)
{
 
    // Initiate vsync interrupt.
    *GS_REG_CSR |= *GS_REG_CSR & 8;
 
    // Wait for vsync interrupt to be generated.
    while (!(*GS_REG_CSR & 8));
 
}