ugfx/3rdparty/tinygl-0.4-ugfx/src/nglx.c
2014-08-20 01:36:33 +10:00

129 lines
3.0 KiB
C

/* simple glx like driver for TinyGL and Nano X */
#include <GL/gl.h>
#include <GL/nglx.h>
#include <microwin/nano-X.h>
#include "zgl.h"
typedef struct {
GLContext *gl_context;
int xsize,ysize;
GR_DRAW_ID drawable;
GR_GC_ID gc;
int pixtype; /* pixel type in TinyGL */
} TinyNGLXContext;
NGLXContext nglXCreateContext(NGLXContext shareList, int flags)
{
TinyNGLXContext *ctx;
if (shareList != NULL) {
gl_fatal_error("No sharing available in TinyGL");
}
ctx=gl_malloc(sizeof(TinyNGLXContext));
if (!ctx)
return NULL;
ctx->gl_context=NULL;
return (NGLXContext) ctx;
}
void glXDestroyContext( NGLXContext ctx1 )
{
TinyNGLXContext *ctx = (TinyNGLXContext *) ctx1;
if (ctx->gl_context != NULL) {
glClose();
}
gl_free(ctx);
}
/* resize the glx viewport : we try to use the xsize and ysize
given. We return the effective size which is guaranted to be smaller */
static int glX_resize_viewport(GLContext *c,int *xsize_ptr,int *ysize_ptr)
{
TinyNGLXContext *ctx;
int xsize,ysize;
ctx=(TinyNGLXContext *)c->opaque;
xsize=*xsize_ptr;
ysize=*ysize_ptr;
/* we ensure that xsize and ysize are multiples of 2 for the zbuffer.
TODO: find a better solution */
xsize&=~3;
ysize&=~3;
if (xsize == 0 || ysize == 0) return -1;
*xsize_ptr=xsize;
*ysize_ptr=ysize;
ctx->xsize=xsize;
ctx->ysize=ysize;
/* resize the Z buffer */
ZB_resize(c->zb,NULL,xsize,ysize);
return 0;
}
/* we assume here that drawable is a window */
int nglXMakeCurrent( NGLXDrawable drawable,
NGLXContext ctx1)
{
TinyNGLXContext *ctx = (TinyNGLXContext *) ctx1;
int mode, xsize, ysize;
ZBuffer *zb;
GR_WINDOW_INFO win_info;
if (ctx->gl_context == NULL) {
/* create the TinyGL context */
GrGetWindowInfo(drawable, &win_info);
xsize = win_info.width;
ysize = win_info.height;
/* currently, we only support 16 bit rendering */
mode = ZB_MODE_5R6G5B;
zb=ZB_open(xsize,ysize,mode,0,NULL,NULL,NULL);
if (zb == NULL) {
fprintf(stderr, "Error while initializing Z buffer\n");
exit(1);
}
ctx->pixtype = MWPF_TRUECOLOR565;
/* create a gc */
ctx->gc = GrNewGC();
/* initialisation of the TinyGL interpreter */
glInit(zb);
ctx->gl_context=gl_get_context();
ctx->gl_context->opaque=(void *) ctx;
ctx->gl_context->gl_resize_viewport=glX_resize_viewport;
/* set the viewport : we force a call to glX_resize_viewport */
ctx->gl_context->viewport.xsize=-1;
ctx->gl_context->viewport.ysize=-1;
glViewport(0, 0, xsize, ysize);
}
return 1;
}
void nglXSwapBuffers( NGLXDrawable drawable )
{
GLContext *gl_context;
TinyNGLXContext *ctx;
/* retrieve the current NGLXContext */
gl_context=gl_get_context();
ctx=(TinyNGLXContext *)gl_context->opaque;
GrArea(drawable, ctx->gc, 0, 0, ctx->xsize,
ctx->ysize, ctx->gl_context->zb->pbuf, ctx->pixtype);
}