graph_vram.c File Reference

#include <gs_psm.h>
#include <graph_vram.h>

Include dependency graph for graph_vram.c:

Go to the source code of this file.

Functions
int	graph_vram_allocate (int width, int height, int psm, int alignment)
void	graph_vram_free (int address)
void	graph_vram_clear (void)
int	graph_vram_size (int width, int height, int psm, int alignment)

Variables
static int	graph_vram_pointer = 0

Function Documentation

graph_vram_allocate()

int graph_vram_allocate	(	int	width,
		int	height,
		int	psm,
		int	alignment
	)

Allocates vram and returns vram base pointer

Definition at line 7 of file graph_vram.c.

{
 
        int size;
 
        // Calculate the size and increment the pointer
        size = graph_vram_size(width,height,psm,alignment);
 
        graph_vram_pointer += size;
 
        // If the pointer overflows the vram size
        if (graph_vram_pointer > GRAPH_VRAM_MAX_WORDS)
        {
 
                graph_vram_pointer -= size;
                return -1;
 
        }
 
        return graph_vram_pointer - size;
 
}

References GRAPH_VRAM_MAX_WORDS, graph_vram_pointer, and graph_vram_size().

Referenced by draw_init_env(), init_gs(), init_texture(), and main().

graph_vram_clear()

void graph_vram_clear

(

void

)

Clears the vram status

Definition at line 37 of file graph_vram.c.

{
 
        graph_vram_pointer = 0;
 
}

References graph_vram_pointer.

graph_vram_free()

void graph_vram_free

(

int

address

)

Frees in FIFO order...

Definition at line 30 of file graph_vram.c.

{
 
        graph_vram_pointer = address;
 
}

References graph_vram_pointer.

Referenced by main().

graph_vram_size()

int graph_vram_size	(	int	width,
		int	height,
		int	psm,
		int	alignment
	)

Calculate the size in vram of a texture or buffer

Definition at line 44 of file graph_vram.c.

{
 
        int size = 0;
 
        // First correct the buffer width to be a multiple of 64 or 128
        // If the width is less than or equal to 16, then it's a palette
        if (width > 16)
        {
                switch (psm)
                {
 
                        case GS_PSM_8:
                        case GS_PSM_4:
                        case GS_PSM_8H:
                        case GS_PSM_4HL:
                        case GS_PSM_4HH:        width = -128 & (width + 127); break;
                        default:                        width = -64  & (width + 63);  break;
 
                }
        }
 
        // Texture storage size is in pixels/word
        switch (psm)
        {
 
                case GS_PSM_4:          size = width*(height>>3); break;
                case GS_PSM_8:          size = width*(height>>2); break;
                case GS_PSM_24:
                case GS_PSM_32:
                case GS_PSM_8H:
                case GS_PSM_4HL:
                case GS_PSM_4HH:
                case GS_PSMZ_24:
                case GS_PSMZ_32:        size = width*height; break;
                case GS_PSM_16:
                case GS_PSM_16S:
                case GS_PSMZ_16:
                case GS_PSMZ_16S:       size = width*(height>>1); break;
                default: return 0;
 
        }
 
        // The buffer size is dependent on alignment
        size = -alignment & (size + (alignment-1));
 
        return size;
 
}

References GS_PSM_16, GS_PSM_16S, GS_PSM_24, GS_PSM_32, GS_PSM_4, GS_PSM_4HH, GS_PSM_4HL, GS_PSM_8, GS_PSM_8H, GS_PSMZ_16, GS_PSMZ_16S, GS_PSMZ_24, and GS_PSMZ_32.

Referenced by graph_vram_allocate().

Variable Documentation

graph_vram_pointer

int graph_vram_pointer = 0

static

Definition at line 5 of file graph_vram.c.

Referenced by graph_vram_allocate(), graph_vram_clear(), and graph_vram_free().