Merge branch 'softres'

5 files changed, 116 insertions, 76 deletions

diff --git a/com32/lib/sys/vesa/background.c b/com32/lib/sys/vesa/background.c
index 815f984c..256c8247 100644
--- a/com32/lib/sys/vesa/background.c
+++ b/com32/lib/sys/vesa/background.c
@@ -44,9 +44,9 @@
    aligned dwords. */
 static void draw_background_line(int line, int start, int npixels)
 {
-    uint32_t *bgptr = &__vesacon_background[line][start];
+    uint32_t *bgptr = &__vesacon_background[line*__vesa_info.mi.h_res+start];
     unsigned int bytes_per_pixel = __vesacon_bytes_per_pixel;
-    size_t fbptr = line * __vesa_info.mi.logical_scan + start * bytes_per_pixel;
+    size_t fbptr = line * __vesa_info.mi.logical_scan + start*bytes_per_pixel;
 
     __vesacon_copy_to_screen(fbptr, bgptr, npixels);
 }
@@ -60,15 +60,17 @@ static void draw_background(void)
     const int right_border = VIDEO_BORDER + (TEXT_PIXEL_COLS % FONT_WIDTH);
 
     for (i = 0; i < VIDEO_BORDER; i++)
-	draw_background_line(i, 0, VIDEO_X_SIZE);
+	draw_background_line(i, 0, __vesa_info.mi.h_res);
 
-    for (i = VIDEO_BORDER; i < VIDEO_Y_SIZE - bottom_border; i++) {
+    for (i = VIDEO_BORDER; i < __vesa_info.mi.v_res - bottom_border; i++) {
 	draw_background_line(i, 0, VIDEO_BORDER);
-	draw_background_line(i, VIDEO_X_SIZE - right_border, right_border);
+	draw_background_line(i, __vesa_info.mi.h_res - right_border,
+			     right_border);
     }
 
-    for (i = VIDEO_Y_SIZE - bottom_border; i < VIDEO_Y_SIZE; i++)
-	draw_background_line(i, 0, VIDEO_X_SIZE);
+    for (i = __vesa_info.mi.v_res - bottom_border;
+	 i < __vesa_info.mi.v_res; i++)
+	draw_background_line(i, 0, __vesa_info.mi.h_res);
 
     __vesacon_redraw_text();
 }
@@ -82,7 +84,7 @@ static int read_png_file(FILE * fp)
     png_color_16p image_background;
     static const png_color_16 my_background = { 0, 0, 0, 0, 0 };
 #endif
-    png_bytep row_pointers[VIDEO_Y_SIZE];
+    png_bytep row_pointers[__vesa_info.mi.v_res], rp;
     int passes;
     int i;
     int rv = -1;
@@ -98,7 +100,7 @@ static int read_png_file(FILE * fp)
     png_init_io(png_ptr, fp);
     png_set_sig_bytes(png_ptr, 8);
 
-    png_set_user_limits(png_ptr, VIDEO_X_SIZE, VIDEO_Y_SIZE);
+    png_set_user_limits(png_ptr, __vesa_info.mi.h_res, __vesa_info.mi.v_res);
 
     png_read_info(png_ptr, info_ptr);
 
@@ -138,8 +140,11 @@ static int read_png_file(FILE * fp)
 #endif
 
     /* Whew!  Now we should get the stuff we want... */
-    for (i = 0; i < (int)info_ptr->height; i++)
-	row_pointers[i] = (void *)__vesacon_background[i];
+    rp = (png_bytep)__vesacon_background;
+    for (i = 0; i < (int)info_ptr->height; i++) {
+	row_pointers[i] = rp;
+	rp += __vesa_info.mi.h_res << 2;
+    }
 
     passes = png_set_interlace_handling(png_ptr);
 
@@ -157,6 +162,7 @@ err:
 static int jpeg_sig_cmp(uint8_t * bytes, int len)
 {
     (void)len;
+
     return (bytes[0] == 0xff && bytes[1] == 0xd8) ? 0 : -1;
 }
 
@@ -183,12 +189,12 @@ static int read_jpeg_file(FILE * fp, uint8_t * header, int len)
 	goto err;
 
     tinyjpeg_get_size(jdec, &width, &height);
-    if (width > VIDEO_X_SIZE || height > VIDEO_Y_SIZE)
+    if (width > __vesa_info.mi.h_res || height > __vesa_info.mi.v_res)
 	goto err;
 
-    components[0] = (void *)&__vesacon_background[0];
+    components[0] = (void *)__vesacon_background;
     tinyjpeg_set_components(jdec, components, 1);
-    bytes_per_row[0] = VIDEO_X_SIZE << 2;
+    bytes_per_row[0] = __vesa_info.mi.h_res << 2;
     tinyjpeg_set_bytes_per_row(jdec, bytes_per_row, 1);
 
     tinyjpeg_decode(jdec, TINYJPEG_FMT_BGRA32);
@@ -217,9 +223,11 @@ int vesacon_default_background(void)
     if (__vesacon_pixel_format == PXF_NONE)
 	return 0;		/* Not in graphics mode */
 
-    for (y = 0, dy = -VIDEO_Y_SIZE / 2; y < VIDEO_Y_SIZE; y++, dy++) {
+    for (y = 0, dy = -__vesa_info.mi.v_res / 2;
+	 y < __vesa_info.mi.v_res; y++, dy++) {
 	dy2 = dy * dy;
-	for (x = 0, dx = -VIDEO_X_SIZE / 2; x < VIDEO_X_SIZE; x++, dx++) {
+	for (x = 0, dx = -__vesa_info.mi.h_res / 2;
+	     x < __vesa_info.mi.h_res; x++, dx++) {
 	    k = __vesacon_linear_to_srgb[500 + ((dx * dx + dy2) >> 6)];
 	    bgptr[0] = k;	/* Blue */
 	    bgptr[1] = k;	/* Green */
@@ -236,7 +244,7 @@ int vesacon_default_background(void)
 int vesacon_set_background(unsigned int rgb)
 {
     void *bgptr = __vesacon_background;
-    unsigned int count = VIDEO_X_SIZE * VIDEO_Y_SIZE;
+    unsigned int count = __vesa_info.mi.h_res * __vesa_info.mi.v_res;
 
     if (__vesacon_pixel_format == PXF_NONE)
 	return 0;		/* Not in graphics mode */
@@ -265,7 +273,8 @@ static inline int lss16_sig_cmp(const void *header, int len)
 	return 1;
 
     return !(h->magic == LSS16_MAGIC &&
-	     h->xsize <= VIDEO_X_SIZE && h->ysize <= VIDEO_Y_SIZE);
+	     h->xsize <= __vesa_info.mi.h_res &&
+	     h->ysize <= __vesa_info.mi.v_res);
 }
 
 static int read_lss16_file(FILE * fp, const void *header, int header_len)
@@ -283,7 +292,7 @@ static int read_lss16_file(FILE * fp, const void *header, int header_len)
 	st_c2,
     } state;
     int i, x, y;
-    uint32_t *bgptr = (void *)__vesacon_background;
+    uint32_t *bgptr = __vesacon_background;
 
     /* Assume the header, 8 bytes, has already been loaded. */
     if (header_len != 8)
@@ -295,7 +304,8 @@ static int read_lss16_file(FILE * fp, const void *header, int header_len)
 	    return -1;
 
 	colors[i] = (((rgb[0] & 63) * 255 / 63) << 16) +
-	    (((rgb[1] & 63) * 255 / 63) << 8) + ((rgb[2] & 63) * 255 / 63);
+	    (((rgb[1] & 63) * 255 / 63) << 8) +
+	    ((rgb[2] & 63) * 255 / 63);
     }
 
     /* By spec, the state machine is per row */
@@ -356,12 +366,12 @@ do_run:
 	}
 
 	/* Zero-fill rest of row */
-	i = VIDEO_X_SIZE - x;
+	i = __vesa_info.mi.h_res - x;
 	asm volatile ("rep; stosl":"+D" (bgptr), "+c"(i):"a"(0):"memory");
     }
 
     /* Zero-fill rest of screen */
-    i = (VIDEO_Y_SIZE - y) * VIDEO_X_SIZE;
+    i = (__vesa_info.mi.v_res - y) * __vesa_info.mi.h_res;
     asm volatile ("rep; stosl":"+D" (bgptr), "+c"(i):"a"(0):"memory");
 
     return 0;
@@ -404,7 +414,7 @@ err:
 
 int __vesacon_init_background(void)
 {
-    /* The BSS clearing has already cleared __vesacon_background */
+    /* __vesacon_background was cleared by calloc() */
 
     /* The VESA BIOS has already cleared the screen */
     return 0;
diff --git a/com32/lib/sys/vesa/drawtxt.c b/com32/lib/sys/vesa/drawtxt.c
index 4b46d678..92d89018 100644
--- a/com32/lib/sys/vesa/drawtxt.c
+++ b/com32/lib/sys/vesa/drawtxt.c
@@ -27,6 +27,7 @@
 
 #include <inttypes.h>
 #include <colortbl.h>
+#include <string.h>
 #include "vesa.h"
 #include "video.h"
 #include "fill.h"
@@ -81,25 +82,20 @@ static void vesacon_update_characters(int row, int col, int nrows, int ncols)
     struct vesa_char *rowptr, *rowsptr, *cptr, *csptr;
     unsigned int bytes_per_pixel = __vesacon_bytes_per_pixel;
     unsigned long pixel_offset;
-    uint32_t row_buffer[VIDEO_X_SIZE], *rowbufptr;
+    uint32_t row_buffer[__vesa_info.mi.h_res], *rowbufptr;
     size_t fbrowptr;
     uint8_t sha;
 
-    bgrowptr =
-	&__vesacon_background[row * height + VIDEO_BORDER][col * width +
-							   VIDEO_BORDER];
-
-    pixel_offset = ((row * height + VIDEO_BORDER) * VIDEO_X_SIZE) +
+    pixel_offset = ((row * height + VIDEO_BORDER) * __vesa_info.mi.h_res) +
 	(col * width + VIDEO_BORDER);
 
+    bgrowptr = &__vesacon_background[pixel_offset];
     fbrowptr = (row * height + VIDEO_BORDER) * __vesa_info.mi.logical_scan +
 	(col * width + VIDEO_BORDER) * bytes_per_pixel;
 
     /* Note that we keep a 1-character guard area around the real text area... */
-    rowptr =
-	&__vesacon_text_display[(row + 1) * (TEXT_PIXEL_COLS / FONT_WIDTH + 2) +
-				(col + 1)];
-    rowsptr = rowptr - ((TEXT_PIXEL_COLS / FONT_WIDTH + 2) + 1);
+    rowptr = &__vesacon_text_display[(row+1)*(__vesacon_text_cols+2)+(col+1)];
+    rowsptr = rowptr - ((__vesacon_text_cols+2)+1);
     pixrow = 0;
     pixsrow = height - 1;
 
@@ -159,7 +155,8 @@ static void vesacon_update_characters(int row, int col, int nrows, int ncols)
 	    }
 
 	    /* If this pixel is raised, use the offsetted value */
-	    bgval = (chxbits & 0x80) ? bgptr[VIDEO_X_SIZE + 1] : *bgptr;
+	    bgval = (chxbits & 0x80)
+		? bgptr[__vesa_info.mi.h_res + 1] : *bgptr;
 	    bgptr++;
 
 	    /* If this pixel is set, use the fg color, else the bg color */
@@ -180,15 +177,15 @@ static void vesacon_update_characters(int row, int col, int nrows, int ncols)
 	/* Copy to frame buffer */
 	__vesacon_copy_to_screen(fbrowptr, row_buffer, rowbufptr - row_buffer);
 
-	bgrowptr += VIDEO_X_SIZE;
+	bgrowptr += __vesa_info.mi.h_res;
 	fbrowptr += __vesa_info.mi.logical_scan;
 
 	if (++pixrow == height) {
-	    rowptr += TEXT_PIXEL_COLS / FONT_WIDTH + 2;
+	    rowptr += __vesacon_text_cols + 2;
 	    pixrow = 0;
 	}
 	if (++pixsrow == height) {
-	    rowsptr += TEXT_PIXEL_COLS / FONT_WIDTH + 2;
+	    rowsptr += __vesacon_text_cols + 2;
 	    pixsrow = 0;
 	}
     }
@@ -232,7 +229,7 @@ void __vesacon_erase(int x0, int y0, int x1, int y1, attr_t attr)
 {
     int y;
     struct vesa_char *ptr = &__vesacon_text_display
-	[(y0 + 1) * (TEXT_PIXEL_COLS / FONT_WIDTH + 2) + (x0 + 1)];
+	[(y0 + 1) * (__vesacon_text_cols + 2) + (x0 + 1)];
     struct vesa_char fill = {
 	.ch = ' ',
 	.attr = attr,
@@ -241,7 +238,7 @@ void __vesacon_erase(int x0, int y0, int x1, int y1, attr_t attr)
 
     for (y = y0; y <= y1; y++) {
 	vesacon_fill(ptr, fill, ncols);
-	ptr += TEXT_PIXEL_COLS / FONT_WIDTH + 2;
+	ptr += __vesacon_text_cols + 2;
     }
 
     vesacon_touch(y0, x0, y1 - y0 + 1, ncols);
@@ -251,11 +248,11 @@ void __vesacon_erase(int x0, int y0, int x1, int y1, attr_t attr)
 void __vesacon_scroll_up(int nrows, attr_t attr)
 {
     struct vesa_char *fromptr = &__vesacon_text_display
-	[(nrows + 1) * (TEXT_PIXEL_COLS / FONT_WIDTH + 2)];
+	[(nrows + 1) * (__vesacon_text_cols + 2)];
     struct vesa_char *toptr = &__vesacon_text_display
-	[(TEXT_PIXEL_COLS / FONT_WIDTH + 2)];
+	[(__vesacon_text_cols + 2)];
     int dword_count =
-	(__vesacon_text_rows - nrows) * (TEXT_PIXEL_COLS / FONT_WIDTH + 2);
+	(__vesacon_text_rows - nrows) * (__vesacon_text_cols + 2);
     struct vesa_char fill = {
 	.ch = ' ',
 	.attr = attr,
@@ -263,18 +260,18 @@ void __vesacon_scroll_up(int nrows, attr_t attr)
 
     toptr = copy_dword(toptr, fromptr, dword_count);
 
-    dword_count = nrows * (TEXT_PIXEL_COLS / FONT_WIDTH + 2);
+    dword_count = nrows * (__vesacon_text_cols + 2);
 
     vesacon_fill(toptr, fill, dword_count);
 
-    vesacon_touch(0, 0, __vesacon_text_rows, TEXT_PIXEL_COLS / FONT_WIDTH);
+    vesacon_touch(0, 0, __vesacon_text_rows, __vesacon_text_cols);
 }
 
 /* Draw one character text at a specific area of the screen */
 void __vesacon_write_char(int x, int y, uint8_t ch, attr_t attr)
 {
     struct vesa_char *ptr = &__vesacon_text_display
-	[(y + 1) * (TEXT_PIXEL_COLS / FONT_WIDTH + 2) + (x + 1)];
+	[(y + 1) * (__vesacon_text_cols + 2) + (x + 1)];
 
     ptr->ch = ch;
     ptr->attr = attr;
@@ -285,7 +282,7 @@ void __vesacon_write_char(int x, int y, uint8_t ch, attr_t attr)
 void __vesacon_set_cursor(int x, int y, int visible)
 {
     struct vesa_char *ptr = &__vesacon_text_display
-	[(y + 1) * (TEXT_PIXEL_COLS / FONT_WIDTH + 2) + (x + 1)];
+	[(y + 1) * (__vesacon_text_cols + 2) + (x + 1)];
 
     if (cursor_pointer)
 	vesacon_touch(cursor_y, cursor_x, 1, 1);
@@ -309,13 +306,12 @@ void __vesacon_init_cursor(int font_height)
     if (r0 < 0)
 	r0 = 0;
 
-    /* cursor_pattern is assumed to be all zero */
+    memset(cursor_pattern, 0, font_height);
     cursor_pattern[r0] = 0xff;
     cursor_pattern[r0 + 1] = 0xff;
 }
 
 void __vesacon_redraw_text(void)
 {
-    vesacon_update_characters(0, 0, __vesacon_text_rows,
-			      TEXT_PIXEL_COLS / FONT_WIDTH);
+    vesacon_update_characters(0, 0, __vesacon_text_rows, __vesacon_text_cols);
 }
diff --git a/com32/lib/sys/vesa/initvesa.c b/com32/lib/sys/vesa/initvesa.c
index 9254683b..0221fcf7 100644
--- a/com32/lib/sys/vesa/initvesa.c
+++ b/com32/lib/sys/vesa/initvesa.c
@@ -46,12 +46,14 @@ struct vesa_info __vesa_info;
 
 struct vesa_char *__vesacon_text_display;
 
-int __vesacon_font_height, __vesacon_text_rows;
+int __vesacon_font_height;
+int __vesacon_text_rows;
+int __vesacon_text_cols;
 enum vesa_pixel_format __vesacon_pixel_format = PXF_NONE;
 unsigned int __vesacon_bytes_per_pixel;
 uint8_t __vesacon_graphics_font[FONT_MAX_CHARS][FONT_MAX_HEIGHT];
 
-uint32_t __vesacon_background[VIDEO_Y_SIZE][VIDEO_X_SIZE];
+uint32_t *__vesacon_background, *__vesacon_shadowfb;
 
 static void unpack_font(uint8_t * dst, uint8_t * src, int height)
 {
@@ -87,7 +89,7 @@ static int vesacon_paged_mode_ok(const struct vesa_mode_info *mi)
     return 0;			/* Nope... */
 }
 
-static int vesacon_set_mode(void)
+static int vesacon_set_mode(int x, int y)
 {
     com32sys_t rm;
     uint8_t *rom_font;
@@ -96,6 +98,16 @@ static int vesacon_set_mode(void)
     struct vesa_mode_info *mi;
     enum vesa_pixel_format pxf, bestpxf;
 
+    /* Free any existing data structures */
+    if (__vesacon_background) {
+	free(__vesacon_background);
+	__vesacon_background = NULL;
+    }
+    if (__vesacon_shadowfb) {
+	free(__vesacon_shadowfb);
+	__vesacon_shadowfb = NULL;
+    }
+
     /* Allocate space in the bounce buffer for these structures */
     gi = &((struct vesa_info *)__com32.cs_bounce)->gi;
     mi = &((struct vesa_info *)__com32.cs_bounce)->mi;
@@ -121,7 +133,7 @@ static int vesacon_set_mode(void)
     /* Copy general info */
     memcpy(&__vesa_info.gi, gi, sizeof *gi);
 
-    /* Search for a 640x480 mode with a suitable color and memory model... */
+    /* Search for the proper mode with a suitable color and memory model... */
 
     mode_ptr = GET_PTR(gi->video_mode_ptr);
     bestmode = 0;
@@ -159,8 +171,8 @@ static int vesacon_set_mode(void)
 	if ((mi->mode_attr & 0x001b) != 0x001b)
 	    continue;
 
-	/* Must be 640x480 */
-	if (mi->h_res != VIDEO_X_SIZE || mi->v_res != VIDEO_Y_SIZE)
+	/* Must be the chosen size */
+	if (mi->h_res != x || mi->v_res != y)
 	    continue;
 
 	/* We don't support multibank (interlaced memory) modes */
@@ -242,9 +254,6 @@ static int vesacon_set_mode(void)
     }
     unpack_font((uint8_t *) __vesacon_graphics_font, rom_font,
 		__vesacon_font_height);
-    __vesacon_text_rows =
-	(VIDEO_Y_SIZE - 2 * VIDEO_BORDER) / __vesacon_font_height;
-    __vesacon_init_cursor(__vesacon_font_height);
 
     /* Now set video mode */
     rm.eax.w[0] = 0x4F02;	/* Set SVGA video mode */
@@ -255,6 +264,9 @@ static int vesacon_set_mode(void)
     if (rm.eax.w[0] != 0x004F)
 	return 9;		/* Failed to set mode */
 
+    __vesacon_background = calloc(mi->h_res*mi->v_res, 4);
+    __vesacon_shadowfb = calloc(mi->h_res*mi->v_res, 4);
+
     __vesacon_init_copy_to_screen();
 
     /* Tell syslinux we changed video mode */
@@ -266,8 +278,8 @@ static int vesacon_set_mode(void)
        However, that would assume all systems that claim to handle text
        output in VESA modes actually do that... */
     rm.ebx.w[0] = 0x000f;
-    rm.ecx.w[0] = VIDEO_X_SIZE;
-    rm.edx.w[0] = VIDEO_Y_SIZE;
+    rm.ecx.w[0] = mi->h_res;
+    rm.edx.w[0] = mi->v_res;
     __intcall(0x22, &rm, NULL);
 
     __vesacon_pixel_format = bestpxf;
@@ -284,8 +296,12 @@ static int init_text_display(void)
 	.attr = 0,
     };
 
-    nchars = (TEXT_PIXEL_ROWS / __vesacon_font_height + 2) *
-	(TEXT_PIXEL_COLS / FONT_WIDTH + 2);
+    if (__vesacon_text_display)
+	free(__vesacon_text_display);
+
+    __vesacon_text_cols = TEXT_PIXEL_COLS / FONT_WIDTH;
+    __vesacon_text_rows = TEXT_PIXEL_ROWS / __vesacon_font_height;
+    nchars = (__vesacon_text_cols+2) * (__vesacon_text_rows+2);
 
     __vesacon_text_display = ptr = malloc(nchars * sizeof(struct vesa_char));
 
@@ -293,11 +309,12 @@ static int init_text_display(void)
 	return -1;
 
     vesacon_fill(ptr, def_char, nchars);
+    __vesacon_init_cursor(__vesacon_font_height);
 
     return 0;
 }
 
-int __vesacon_init(void)
+int __vesacon_init(int x, int y)
 {
     int rv;
 
@@ -305,7 +322,7 @@ int __vesacon_init(void)
     if (x86_init_fpu())
 	return 10;
 
-    rv = vesacon_set_mode();
+    rv = vesacon_set_mode(x, y);
     if (rv)
 	return rv;
 
diff --git a/com32/lib/sys/vesa/video.h b/com32/lib/sys/vesa/video.h
index b02b5ae7..0bd1abff 100644
--- a/com32/lib/sys/vesa/video.h
+++ b/com32/lib/sys/vesa/video.h
@@ -29,17 +29,18 @@
 #define LIB_SYS_VESA_VIDEO_H
 
 #include <colortbl.h>
+#include "vesa.h"
 
 #define FONT_MAX_CHARS	256
 #define FONT_MAX_HEIGHT	 32
 #define FONT_WIDTH	  8
 
-#define VIDEO_X_SIZE	640
-#define VIDEO_Y_SIZE	480
+#define DEFAULT_VESA_X_SIZE	640
+#define DEFAULT_VESA_Y_SIZE	480
 
 #define VIDEO_BORDER	8
-#define TEXT_PIXEL_ROWS (VIDEO_Y_SIZE-2*VIDEO_BORDER)
-#define TEXT_PIXEL_COLS (VIDEO_X_SIZE-2*VIDEO_BORDER)
+#define TEXT_PIXEL_ROWS (__vesa_info.mi.v_res - 2*VIDEO_BORDER)
+#define TEXT_PIXEL_COLS (__vesa_info.mi.h_res - 2*VIDEO_BORDER)
 
 typedef uint16_t attr_t;
 
@@ -60,24 +61,26 @@ enum vesa_pixel_format {
 };
 extern enum vesa_pixel_format __vesacon_pixel_format;
 extern unsigned int __vesacon_bytes_per_pixel;
-typedef const void *(*__vesacon_format_pixels_t) (void *, const uint32_t *,
-						  size_t);
+typedef const void *(*__vesacon_format_pixels_t)
+    (void *, const uint32_t *, size_t);
 extern __vesacon_format_pixels_t __vesacon_format_pixels;
 extern const __vesacon_format_pixels_t __vesacon_format_pixels_list[PXF_NONE];
 
 extern struct vesa_char *__vesacon_text_display;
 
-extern int __vesacon_font_height, __vesacon_text_rows;
+extern int __vesacon_font_height;
+extern int __vesacon_text_rows;
+extern int __vesacon_text_cols;
 extern uint8_t __vesacon_graphics_font[FONT_MAX_CHARS][FONT_MAX_HEIGHT];
-extern uint32_t __vesacon_background[VIDEO_Y_SIZE][VIDEO_X_SIZE];
-extern uint32_t __vesacon_shadowfb[VIDEO_Y_SIZE][VIDEO_X_SIZE];
+extern uint32_t *__vesacon_background;
+extern uint32_t *__vesacon_shadowfb;
 
 extern const uint16_t __vesacon_srgb_to_linear[256];
 extern const uint8_t __vesacon_linear_to_srgb[4080];
 
 int __vesacon_init_background(void);
 int vesacon_load_background(const char *);
-int __vesacon_init(void);
+int __vesacon_init(int, int);
 void __vesacon_init_cursor(int);
 void __vesacon_erase(int, int, int, int, attr_t);
 void __vesacon_scroll_up(int, attr_t);
diff --git a/com32/lib/sys/vesacon_write.c b/com32/lib/sys/vesacon_write.c
index f0fc845f..e85aba88 100644
--- a/com32/lib/sys/vesacon_write.c
+++ b/com32/lib/sys/vesacon_write.c
@@ -61,7 +61,6 @@ static struct ansi_ops op = {
 };
 
 static struct term_info ti = {
-    .cols = TEXT_PIXEL_COLS / FONT_WIDTH,
     .disabled = 0,
     .ts = &ts,
     .op = &op
@@ -71,6 +70,20 @@ static struct term_info ti = {
    reinitialization. */
 static int vesacon_counter = 0;
 
+static struct {
+    int x, y;
+} vesacon_resolution = {
+    .x = DEFAULT_VESA_X_SIZE,
+    .y = DEFAULT_VESA_Y_SIZE,
+};
+
+/* Set desired resolution - requires a full close/open cycle */
+void vesacon_set_resolution(int x, int y)
+{
+    vesacon_resolution.x = x;
+    vesacon_resolution.y = y;
+}
+
 /* Common setup */
 int __vesacon_open(struct file_info *fp)
 {
@@ -84,7 +97,7 @@ int __vesacon_open(struct file_info *fp)
 	    ti.cols = 80;
 	} else {
 	    /* Switch mode */
-	    if (__vesacon_init()) {
+	    if (__vesacon_init(vesacon_resolution.x, vesacon_resolution.y)) {
 		vesacon_counter = -1;
 		return EAGAIN;
 	    }
@@ -92,6 +105,7 @@ int __vesacon_open(struct file_info *fp)
 	    /* Initial state */
 	    __ansi_init(&ti);
 	    ti.rows = __vesacon_text_rows;
+	    ti.cols = __vesacon_text_cols;
 	}
     } else if (vesacon_counter == -1) {
 	return EAGAIN;