pulled in and adapted the dos code from eradicate
[retrobench] / src / dos / gfx.c
diff --git a/src/dos/gfx.c b/src/dos/gfx.c
new file mode 100644 (file)
index 0000000..c8444aa
--- /dev/null
@@ -0,0 +1,307 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "cdpmi.h"
+#include "gfx.h"
+#include "vbe.h"
+#include "vga.h"
+#include "util.h"
+
+#define SAME_BPP(a, b) \
+       ((a) == (b) || ((a) == 16 && (b) == 15) || ((a) == 15 && (b) == 16) || \
+        ((a) == 32 && (b) == 24) || ((a) == 24 && (b) == 32))
+
+void (*blit_frame)(void*, int);
+
+int resizefb(int x, int y, int bpp);
+
+static void blit_frame_lfb(void *pixels, int vsync);
+static void blit_frame_banked(void *pixels, int vsync);
+static uint32_t calc_mask(int sz, int pos);
+
+static struct video_mode *vmodes;
+static int num_vmodes;
+
+static int vbe_init_ver;
+static struct vbe_info vbe;
+
+/* current mode */
+static struct video_mode *curmode;
+static void *vpgaddr[2];
+static int frontidx, backidx;
+static int pgcount, pgsize, fbsize;
+
+
+int init_video(void)
+{
+       int i, num, max_modes;
+       struct video_mode *vmptr;
+
+       if(vbe_info(&vbe) == -1) {
+               fprintf(stderr, "failed to retrieve VBE information\n");
+               return -1;
+       }
+       vbe_print_info(stdout, &vbe);
+
+       num_vmodes = 0;
+       max_modes = 64;
+       if(!(vmodes = malloc(max_modes * sizeof *vmodes))) {
+               fprintf(stderr, "failed to allocate video modes list\n");
+               return -1;
+       }
+
+       num = vbe_num_modes(&vbe);
+       for(i=0; i<num; i++) {
+               struct vbe_mode_info minf;
+
+               if(vbe_mode_info(vbe.modes[i], &minf) == -1) {
+                       continue;
+               }
+
+               if(num_vmodes >= max_modes) {
+                       int newmax = max_modes ? (max_modes << 1) : 16;
+                       if(!(vmptr = realloc(vmodes, newmax * sizeof *vmodes))) {
+                               fprintf(stderr, "failed to grow video mode list (%d)\n", newmax);
+                               free(vmodes);
+                               return -1;
+                       }
+                       vmodes = vmptr;
+                       max_modes = newmax;
+               }
+
+               vmptr = vmodes + num_vmodes++;
+               memset(vmptr, 0, sizeof *vmptr);
+               vmptr->mode = vbe.modes[i];
+               vmptr->xsz = minf.xres;
+               vmptr->ysz = minf.yres;
+               vmptr->bpp = minf.bpp;
+               vmptr->pitch = minf.scanline_bytes;
+               if(minf.mem_model == VBE_TYPE_DIRECT) {
+                       vmptr->rbits = minf.rsize;
+                       vmptr->gbits = minf.gsize;
+                       vmptr->bbits = minf.bsize;
+                       vmptr->rshift = minf.rpos;
+                       vmptr->gshift = minf.gpos;
+                       vmptr->bshift = minf.bpos;
+                       vmptr->rmask = calc_mask(minf.rsize, minf.rpos);
+                       vmptr->gmask = calc_mask(minf.gsize, minf.gpos);
+                       vmptr->bmask = calc_mask(minf.bsize, minf.bpos);
+                       vmptr->bpp = vmptr->rbits + vmptr->gbits + vmptr->bbits;
+               }
+               if(minf.attr & VBE_ATTR_LFB) {
+                       vmptr->fb_addr = minf.fb_addr;
+               } else {
+                       vmptr->bank_size = (uint32_t)minf.bank_size * 1024;
+                       if(!vmptr->bank_size) {
+                               vmptr->bank_size = 65536;
+                       }
+               }
+               vmptr->max_pages = minf.num_img_pages;
+
+               printf("%04x: ", vbe.modes[i]);
+               vbe_print_mode_info(stdout, &minf);
+       }
+       fflush(stdout);
+
+       vbe_init_ver = VBE_VER_MAJOR(vbe.ver);
+       return 0;
+}
+
+void cleanup_video(void)
+{
+       free(vmodes);
+}
+
+struct video_mode *video_modes(void)
+{
+       return vmodes;
+}
+
+int num_video_modes(void)
+{
+       return num_vmodes;
+}
+
+struct video_mode *get_video_mode(int idx)
+{
+       if(idx == VMODE_CURRENT) {
+               return curmode;
+       }
+       return vmodes + idx;
+}
+
+int match_video_mode(int xsz, int ysz, int bpp)
+{
+       int i, best = -1;
+       struct video_mode *vm;
+
+       for(i=0; i<num_vmodes; i++) {
+               vm = vmodes + i;
+               if(vm->xsz != xsz || vm->ysz != ysz) continue;
+               if(SAME_BPP(vm->bpp, bpp)) {
+                       best = i;
+               }
+               if(vm->bpp == bpp) break;
+       }
+
+       if(best == -1) {
+               fprintf(stderr, "failed to find video mode %dx%d %d bpp)\n", xsz, ysz, bpp);
+               return -1;
+       }
+       return best;
+}
+
+int find_video_mode(int mode)
+{
+       int i;
+       struct video_mode *vm;
+
+       vm = vmodes;
+       for(i=0; i<num_vmodes; i++) {
+               if(vm->mode == mode) return i;
+       }
+       return -1;
+}
+
+void *set_video_mode(int idx, int nbuf)
+{
+       unsigned int mode;
+       struct video_mode *vm = vmodes + idx;
+
+       if(curmode == vm) return vpgaddr[0];
+
+       printf("setting video mode %x (%dx%d %d bpp)\n", (unsigned int)vm->mode,
+                       vm->xsz, vm->ysz, vm->bpp);
+       fflush(stdout);
+
+       mode = vm->mode | VBE_MODE_LFB;
+       if(vbe_setmode(mode) == -1) {
+               mode = vm->mode;
+               if(vbe_setmode(mode) == -1) {
+                       fprintf(stderr, "failed to set video mode %x\n", (unsigned int)vm->mode);
+                       return 0;
+               }
+               printf("Warning: failed to get a linear framebuffer. falling back to banked mode\n");
+       }
+
+       /* unmap previous video memory mapping, if there was one (switching modes) */
+       if(vpgaddr[0] && vpgaddr[0] != (void*)0xa0000) {
+               dpmi_munmap(vpgaddr[0]);
+               vpgaddr[0] = vpgaddr[1] = 0;
+       }
+
+       curmode = vm;
+       if(nbuf < 1) nbuf = 1;
+       if(nbuf > 2) nbuf = 2;
+       pgcount = nbuf > vm->max_pages ? vm->max_pages : nbuf;
+       pgsize = vm->ysz * vm->pitch;
+       fbsize = pgcount * pgsize;
+
+       printf("pgcount: %d, pgsize: %d, fbsize: %d\n", pgcount, pgsize, fbsize);
+       printf("phys addr: %p\n", (void*)vm->fb_addr);
+       fflush(stdout);
+
+       if(vm->fb_addr) {
+               vpgaddr[0] = (void*)dpmi_mmap(vm->fb_addr, fbsize);
+               if(!vpgaddr[0]) {
+                       fprintf(stderr, "failed to map framebuffer (phys: %lx, size: %d)\n",
+                                       (unsigned long)vm->fb_addr, fbsize);
+                       set_text_mode();
+                       return 0;
+               }
+               memset(vpgaddr[0], 0xaa, pgsize);
+
+               if(pgcount > 1) {
+                       vpgaddr[1] = (char*)vpgaddr[0] + pgsize;
+                       backidx = 1;
+                       page_flip(FLIP_NOW);    /* start with the second page visible */
+               } else {
+                       frontidx = backidx = 0;
+                       vpgaddr[1] = 0;
+               }
+
+               blit_frame = blit_frame_lfb;
+
+       } else {
+               vpgaddr[0] = (void*)0xa0000;
+               vpgaddr[1] = 0;
+
+               blit_frame = blit_frame_banked;
+       }
+
+       /* allocate main memory framebuffer */
+       if(resizefb(vm->xsz, vm->ysz, vm->bpp) == -1) {
+               fprintf(stderr, "failed to allocate %dx%d (%d bpp) framebuffer\n", vm->xsz,
+                               vm->ysz, vm->bpp);
+               set_text_mode();
+               return 0;
+       }
+
+       return vpgaddr[0];
+}
+
+int set_text_mode(void)
+{
+       /* unmap previous video memory mapping, if there was one (switching modes) */
+       if(vpgaddr[0] && vpgaddr[0] != (void*)0xa0000) {
+               dpmi_munmap(vpgaddr[0]);
+               vpgaddr[0] = vpgaddr[1] = 0;
+       }
+
+       vga_setmode(3);
+       curmode = 0;
+       return 0;
+}
+
+void *page_flip(int vsync)
+{
+       if(!vpgaddr[1]) {
+               /* page flipping not supported */
+               return vpgaddr[0];
+       }
+
+       vbe_swap(backidx ? pgsize : 0, vsync ? VBE_SWAP_VBLANK : VBE_SWAP_NOW);
+       frontidx = backidx;
+       backidx = (backidx + 1) & 1;
+
+       return vpgaddr[backidx];
+}
+
+
+static void blit_frame_lfb(void *pixels, int vsync)
+{
+       if(vsync) wait_vsync();
+       memcpy64(vpgaddr[frontidx], pixels, pgsize >> 3);
+}
+
+static void blit_frame_banked(void *pixels, int vsync)
+{
+       int sz, offs;
+       unsigned int pending;
+       unsigned char *pptr = pixels;
+
+       if(vsync) wait_vsync();
+
+       /* assume initial window offset at 0 */
+       offs = 0;
+       pending = pgsize;
+       while(pending > 0) {
+               sz = pending > curmode->bank_size ? curmode->bank_size : pending;
+               //memcpy64((void*)0xa0000, pptr, sz >> 3);
+               memcpy((void*)0xa0000, pptr, sz);
+               pptr += sz;
+               pending -= sz;
+               vbe_setwin(0, ++offs);
+       }
+
+       vbe_setwin(0, 0);
+}
+
+static uint32_t calc_mask(int sz, int pos)
+{
+       uint32_t mask = 0;
+       while(sz-- > 0) {
+               mask = (mask << 1) | 1;
+       }
+       return mask << pos;
+}