Add simple drawing code & font loading.

4 files changed, 394 insertions, 1 deletions

diff --git a/src/lib/include/draw.h b/src/lib/include/draw.h
new file mode 100644
index 0000000..893c5a3
--- /dev/null
+++ b/src/lib/include/draw.h
@@ -0,0 +1,62 @@
+#pragma once
+
+#include <syscall.h>
+#include <proto/fb.h>
+
+//  ---- Generic drawing functions
+
+//  ---- Data structures
+
+typedef struct {
+	fb_info_t geom;
+
+	fd_t fd;
+	uint8_t* data;
+} fb_t;
+
+typedef struct font font_t;
+
+typedef uint32_t color_t;	// a color is always linked to a FB on which it is to be applied
+
+//  ---- Buffer creation
+
+fb_t *g_fb_from_file(fd_t file, fb_info_t *geom);
+fb_t *g_fb_from_mem(uint8_t* region, fb_info_t *geom);
+
+void g_delete_fb(fb_t *fb);
+
+//  ---- Color manipulation
+
+color_t g_color_rgb(fb_t *f, uint8_t r, uint8_t g, uint8_t b);
+
+//  ---- Drawing primitives
+
+void g_plot(fb_t *fb, int x, int y, color_t c);
+
+void g_hline(fb_t *fb, int x, int y, int w, color_t c);		// horizontal line
+void g_vline(fb_t *fb, int x, int y, int h, color_t c);		// vertical line
+void g_line(fb_t *fb, int x1, int y1, int x2, int y2, color_t c);
+
+void g_rect(fb_t *fb, int x, int y, int w, int h, color_t c);
+void g_fillrect(fb_t *fb, int x, int y, int w, int h, color_t c);
+void g_rect_r(fb_t *fb, fb_region_t reg, color_t c);
+void g_fillrect_r(fb_t *fb, fb_region_t reg, color_t c);
+
+void g_circle(fb_t *fb, int cx, int cy, int r, color_t c);
+void g_fillcircle(fb_t *fb, int cx, int cy, int r, color_t c);
+
+void g_blit(fb_t *dst, int x, int y, fb_t *src);
+void g_blit_region(fb_t *dst, int x, int y, fb_t *src, fb_region_t reg);
+
+//  ---- Text manipulation
+
+font_t *g_load_font(const char* fontname);
+void g_free_font(font_t *f);
+
+int g_text_width(font_t *f, const char* text);
+int g_text_height(font_t *f, const char* text);
+
+void g_write(fb_t *fb, int x, int y, const char* text, font_t *font, color_t c);
+
+
+/* vim: set ts=4 sw=4 tw=0 noet :*/
diff --git a/src/lib/include/proto/font_file.h b/src/lib/include/proto/font_file.h
new file mode 100644
index 0000000..e57c0ab
--- /dev/null
+++ b/src/lib/include/proto/font_file.h
@@ -0,0 +1,14 @@
+#pragma once
+
+#include <stdint.h>
+#include <stddef.h>
+
+#define ASCII_BITMAP_FONT_MAGIC 0xD184C274
+
+typedef struct {
+	uint32_t magic;
+	uint16_t cw, ch;
+	uint32_t nchars;
+} ascii_bitmap_font_header;
+
+/* vim: set ts=4 sw=4 tw=0 noet :*/
diff --git a/src/lib/libkogata/Makefile b/src/lib/libkogata/Makefile
index 48c6bc2..a8df419 100644
--- a/src/lib/libkogata/Makefile
+++ b/src/lib/libkogata/Makefile
@@ -1,5 +1,5 @@
 OBJ = start.o malloc.o debug.o syscall.o user_region.o \
-	mainloop.o gip.o
+	mainloop.o gip.o draw.o
 
 LIB = ../../common/libkogata/libkogata.lib ../../common/libalgo/libalgo.lib ../../common/libc/libc.lib
 
diff --git a/src/lib/libkogata/draw.c b/src/lib/libkogata/draw.c
new file mode 100644
index 0000000..22ad8ba
--- /dev/null
+++ b/src/lib/libkogata/draw.c
@@ -0,0 +1,317 @@
+#include <syscall.h>
+#include <malloc.h>
+#include <string.h>
+#include <printf.h>
+
+#include <proto/font_file.h>
+
+#include <user_region.h>
+
+#include <draw.h>
+
+fb_t *g_fb_from_file(fd_t file, fb_info_t *geom) {
+	fb_t *ret = (fb_t*)malloc(sizeof(fb_t));
+	if (ret == 0) return 0;
+
+	memcpy(&ret->geom, geom, sizeof(fb_info_t));
+	ret->fd = file;
+
+	ret->data = (uint8_t*)region_alloc(geom->height * geom->pitch, "Framebuffer");
+	if (ret->data == 0) goto error;
+
+	bool map_ok = mmap_file(file, 0, ret->data, geom->height * geom->pitch, MM_READ | MM_WRITE);
+	if (!map_ok) goto error;
+
+	return ret;
+
+error:
+	if (ret && ret->data) region_free(ret->data);
+	if (ret) free(ret);
+	return 0;
+}
+
+fb_t *g_fb_from_mem(uint8_t* data, fb_info_t *geom) {
+	fb_t *ret = (fb_t*)malloc(sizeof(fb_t));
+	if (ret == 0) return 0;
+
+	memcpy(&ret->geom, geom, sizeof(fb_info_t));
+	ret->fd = 0;
+	ret->data = data;
+
+	return ret;
+}
+
+void g_delete_fb(fb_t *fb) {
+	if (fb->fd != 0) {
+		munmap(fb->data);
+		region_free(fb->data);
+	}
+	free(fb);
+}
+
+//  ---- Color management
+
+color_t g_color_rgb(fb_t *f, uint8_t r, uint8_t g, uint8_t b) {
+	int m = f->geom.memory_model;
+	if (m == FB_MM_RGB24 || m == FB_MM_RGB32) return (r << 16) | (g << 8) | b;
+	if (m == FB_MM_BGR24 || m == FB_MM_BGR32) return (b << 16) | (g << 8) | r;
+	if (m == FB_MM_GREY8) return ((r + g + b) / 3) & 0xFF;
+	if (m == FB_MM_RGB16 || m == FB_MM_RGB15) return ((r >> 3) << 10) | ((g >> 3) << 5) | (b >> 3);
+	if (m == FB_MM_BGR16 || m == FB_MM_BGR15) return ((b >> 3) << 10) | ((g >> 3) << 5) | (r >> 3);
+	return 0;	// unknown?
+}
+
+//  ---- Plot
+
+inline void g_plot24(uint8_t* p, color_t c) {
+	p[0] = c & 0xFF;
+	p[1] = (c >> 8) & 0xFF;
+	p[2] = (c >> 16) & 0xFF;
+}
+
+void g_plot(fb_t *fb, int x, int y, color_t c) {
+	if (fb->geom.bpp == 8) {
+		fb->data[y * fb->geom.pitch + x] = (c & 0xFF);
+	} else if (fb->geom.bpp == 15 || fb->geom.bpp == 16) {
+		uint16_t *p = (uint16_t*)(fb->data + y * fb->geom.pitch + 2 * x);
+		*p = (c & 0xFFFF);
+	} else if (fb->geom.bpp == 24) {
+		g_plot24(fb->data + y * fb->geom.pitch + 3 * x, c);
+	} else if (fb->geom.bpp == 32) {
+		uint32_t *p = (uint32_t*)(fb->data + y * fb->geom.pitch + 4 * x);
+		*p = c;
+	}
+}
+
+void g_hline(fb_t *fb, int x, int y, int w, color_t c) {
+	if (fb->geom.bpp == 8) {
+		for (int u = x; u < x + w; u++) {
+			fb->data[y * fb->geom.pitch + u] = (c & 0xFF);
+		}
+	} else if (fb->geom.bpp == 15 || fb->geom.bpp == 15) {
+		for (int u = x; u < x + w; u++) {
+			uint16_t *p = (uint16_t*)(fb->data + y * fb->geom.pitch + 2 * u);
+			*p = (c & 0xFFFF);
+		}
+	} else if (fb->geom.bpp == 24) {
+		for (int u = x; u < x + w; u++) {
+			g_plot24(fb->data + y * fb->geom.pitch + 3 * u, c);
+		}
+	} else if (fb->geom.bpp == 32) {
+		for (int u = x; u < x + w; u++) {
+			uint32_t *p = (uint32_t*)(fb->data + y * fb->geom.pitch + 4 * u);
+			*p = c;
+		}
+	}
+}
+
+void g_vline(fb_t *fb, int x, int y, int h, color_t c) {
+	if (fb->geom.bpp == 8) {
+		for (int v = y; v < y + h; v++) {
+			fb->data[v * fb->geom.pitch + x] = (c & 0xFF);
+		}
+	} else if (fb->geom.bpp == 15 || fb->geom.bpp == 15) {
+		for (int v = y; v < y + h; v++) {
+			uint16_t *p = (uint16_t*)(fb->data + v * fb->geom.pitch + 2 * x);
+			*p = (c & 0xFFFF);
+		}
+	} else if (fb->geom.bpp == 24) {
+		for (int v = y; v < y + h; v++) {
+			g_plot24(fb->data + v * fb->geom.pitch + 3 * x, c);
+		}
+	} else if (fb->geom.bpp == 32) {
+		for (int v = y; v < y + h; v++) {
+			uint32_t *p = (uint32_t*)(fb->data + v * fb->geom.pitch + 4 * x);
+			*p = c;
+		}
+	}
+}
+
+void g_line(fb_t *fb, int x1, int y1, int x2, int y2, color_t c) {
+	// TODO
+}
+
+void g_rect(fb_t *fb, int x, int y, int w, int h, color_t c) {
+	g_hline(fb, x, y, w, c);
+	g_hline(fb, x, y+h-1, w, c);
+	g_vline(fb, x, y, h, c);
+	g_vline(fb, x+w-1, y, h, c);
+}
+
+void g_fillrect(fb_t *fb, int x, int y, int w, int h, color_t c) {
+	if (fb->geom.bpp == 8) {
+		for (int v = y; v < y + h; v++) {
+			for (int u = x; u < x + w; u++) {
+				fb->data[v * fb->geom.pitch + u] = (c & 0xFF);
+			}
+		}
+	} else if (fb->geom.bpp == 15 || fb->geom.bpp == 15) {
+		for (int v = y; v < y + h; v++) {
+			for (int u = x; u < x + w; u++) {
+				uint16_t *p = (uint16_t*)(fb->data + v * fb->geom.pitch + 2 * u);
+				*p = (c & 0xFFFF);
+			}
+		}
+	} else if (fb->geom.bpp == 24) {
+		for (int v = y; v < y + h; v++) {
+			for (int u = x; u < x + w; u++) {
+				g_plot24(fb->data + v * fb->geom.pitch + 3 * u, c);
+			}
+		}
+	} else if (fb->geom.bpp == 32) {
+		for (int v = y; v < y + h; v++) {
+			for (int u = x; u < x + w; u++) {
+				uint32_t *p = (uint32_t*)(fb->data + v * fb->geom.pitch + 4 * u);
+				*p = c;
+			}
+		}
+	}
+}
+
+void g_rect_r(fb_t *fb, fb_region_t reg, color_t c) {
+	g_rect(fb, reg.x, reg.y, reg.w, reg.h, c);
+}
+
+void g_fillrect_r(fb_t *fb, fb_region_t reg, color_t c) {
+	g_fillrect(fb, reg.x, reg.y, reg.w, reg.h, c);
+}
+
+void g_circle(fb_t *fb, int cx, int cy, int r, color_t c) {
+	// TODO
+}
+
+void g_fillcircle(fb_t *fb, int cx, int cy, int r, color_t c) {
+	// TODO
+}
+
+void g_blit(fb_t *dst, int x, int y, fb_t *src) {
+	fb_region_t r;
+
+	r.x = 0;
+	r.y = 0;
+	r.w = src->geom.width;
+	r.h = src->geom.height;
+
+	g_blit_region(dst, x, y, src, r);
+}
+
+void g_blit_region(fb_t *dst, int x, int y, fb_t *src, fb_region_t reg) {
+	if (src->geom.memory_model == dst->geom.memory_model) {
+		for (uint32_t i = 0; i < reg.h; i++) {
+			memcpy(
+				dst->data + (y + i) * dst->geom.pitch + x * (dst->geom.bpp / 8),
+				src->data + (reg.y + i) * src->geom.pitch + reg.x * (src->geom.bpp / 8),
+				reg.w * (src->geom.bpp / 8));
+		}
+	} else {
+		dbg_printf("Unsupported blit between different memory models.\n");
+	}
+}
+
+//  ---- Text manipulation
+
+#define FONT_ASCII_BITMAP	1
+// more font types to come
+
+typedef struct font {
+	int type;
+	union {
+		struct {
+			uint8_t* data;
+			uint8_t cw, ch;		// width, height of a character
+			uint32_t nchars;
+		} ascii_bitmap;
+	};
+} font_t;
+
+font_t *g_load_ascii_bitmap_font(fd_t f) {
+	font_t *font = 0;
+
+	ascii_bitmap_font_header h;
+
+	size_t s = read(f, 0, sizeof(h), (char*)&h);
+	if (s != sizeof(h)) goto error;
+
+	if (h.magic != ASCII_BITMAP_FONT_MAGIC) goto error;
+	if (h.cw != 8) goto error;
+
+	font = malloc(sizeof(font_t));
+	if (font == 0) goto error;
+	memset(font, 0, sizeof(font_t));
+
+
+	font->type = FONT_ASCII_BITMAP;
+	font->ascii_bitmap.cw = h.cw;
+	font->ascii_bitmap.ch = h.ch;
+	font->ascii_bitmap.nchars = h.nchars;
+
+
+	font->ascii_bitmap.data = (uint8_t*)malloc(h.ch * h.nchars);
+	if (font->ascii_bitmap.data == 0) goto error;
+
+	size_t rd = read(f, sizeof(h), h.ch * h.nchars, (char*)font->ascii_bitmap.data);
+	if (rd != h.ch * h.nchars) goto error;
+
+	return font;
+
+error:
+	if (font && font->ascii_bitmap.data) free(font->ascii_bitmap.data);
+	if (font) free(font);
+	close(f);
+	return 0;
+}
+
+font_t *g_load_font(const char* fontname) {
+	char buf[128];
+
+	snprintf(buf, 128, "sys:/fonts/%s.bf", fontname);
+	fd_t f = open(buf, FM_READ);
+	if (f != 0) return g_load_ascii_bitmap_font(f);
+
+	return 0;
+}
+
+void g_free_font(font_t *f) {
+	if (f->type == FONT_ASCII_BITMAP) {
+		free(f->ascii_bitmap.data);
+	}
+
+	free(f);
+}
+
+int g_text_width(font_t *font, const char* text) {
+	if (font->type == FONT_ASCII_BITMAP) {
+		return font->ascii_bitmap.cw * strlen(text);
+	}
+	return 0;
+}
+
+int g_text_height(font_t *font, const char* text) {
+	if (font->type == FONT_ASCII_BITMAP) {
+		return font->ascii_bitmap.ch;
+	}
+	return 0;
+}
+
+void g_write(fb_t *fb, int x, int y, const char* text, font_t *font, color_t c) {
+	if (font->type == FONT_ASCII_BITMAP) {
+		while (*text != 0) {
+			uint8_t id = (uint8_t)*text;
+			if (id < font->ascii_bitmap.nchars) {
+				uint8_t *d = font->ascii_bitmap.data + (id * font->ascii_bitmap.ch);
+				for (int r = 0; r < font->ascii_bitmap.ch; r++) {
+					for (int j = 0; j < 8; j++) {
+						if (d[r] & (0x80 >> j)) {
+							g_plot(fb, x + j, y + r, c);
+						}
+					}
+				}
+			}
+			text++;
+			x += font->ascii_bitmap.cw;
+		}
+	}
+}
+
+
+/* vim: set ts=4 sw=4 tw=0 noet :*/