lib: Introduce libgfx

This commit introduces libgfx which is a low-level graphics library
and does not know anything about windows, display architecture, etc.
The job of libgfx is soley to provide an API to draw shapes, graphical objects
and perform operations on them.

Signed-off-by: Ian Moffett <ian@osmora.org>

6 files changed, 400 insertions, 0 deletions

diff --git a/lib/Makefile b/lib/Makefile
index a201891..4ad104b 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -6,3 +6,4 @@ ARGS = -I$(ROOT)/builddeps LDSCRIPT=$(LDSCRIPT) USRDIR=$(USRDIR) ROOT=$(ROOT)
 .PHONY: all
 all:
 	make -C libc/ $(ARGS)
+	make -C libgfx/ $(ARGS)
diff --git a/lib/libgfx/Makefile b/lib/libgfx/Makefile
new file mode 100644
index 0000000..1f866ac
--- /dev/null
+++ b/lib/libgfx/Makefile
@@ -0,0 +1,30 @@
+CFLAGS = -c -fno-stack-protector -nostdlib -static \
+		 -Iinclude/ -I$(USRDIR)/include/
+CFILES = $(shell find src/ -name "*.c")
+OBJ = $(CFILES:.c=.o)
+
+all: headers $(OBJ) build/libgfx.a
+	echo "----------------------------------------"
+	echo $(USRDIR)
+	mv build/libgfx.a $(USRDIR)/lib/
+	cp -r include/ $(USRDIR)/include/
+
+build/libgfx.a:
+	mkdir -p build/
+	ar rcs build/libgfx.a $(OBJ)
+
+%.o: %.c
+	$(CC) $(CFLAGS) -Iinclude/ $< -o $@
+
+.PHONY: headers
+headers:
+	cp -rf include/* $(USRDIR)/include/
+
+.PHONY:
+build/:
+	mkdir -p build/
+
+.PHONY: clean
+clean:
+	rm -f $(OBJ)
+	rm -rf build/
diff --git a/lib/libgfx/include/libgfx/draw.h b/lib/libgfx/include/libgfx/draw.h
new file mode 100644
index 0000000..60d2b24
--- /dev/null
+++ b/lib/libgfx/include/libgfx/draw.h
@@ -0,0 +1,91 @@
+/*
+ * Copyright (c) 2023-2025 Ian Marco Moffett and the Osmora Team.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of Hyra nor the names of its
+ *    contributors may be used to endorse or promote products derived from
+ *    this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef _LIBGFX_DRAW_H_
+#define _LIBGFX_DRAW_H_
+
+#include <stdint.h>
+#include <libgfx/gfx.h>
+
+/* Shape types */
+#define SHAPE_SQUARE  0x00000000
+
+/*
+ * Default shape initializer, something that
+ * works and can be tweaked. The idea of this
+ * is so that shapes may be set up like so:
+ *
+ * --
+ * struct gfx_shape blah = GFX_SHAPE_DEFAULT;
+ *
+ * blah.width = width;
+ * blah.heiht = height;
+ * ...
+ * --
+ */
+#define GFX_SHAPE_DEFAULT       \
+    {                           \
+        .type = SHAPE_SQUARE,   \
+        .color = 0x00FF00,      \
+        .x = 0,                 \
+        .y = 0,                 \
+        .width = 50,            \
+        .height = 50,           \
+    }
+
+/*
+ * Generic shape representation
+ *
+ * @type: Shape type (see SHAPE_*)
+ * @color: Color of the shape
+ * @x: X position of the shape
+ * @y: Y position of the shape
+ * @width: Shape width
+ * @height: Shape height
+ */
+struct gfx_shape {
+    uint32_t type;
+    color_t color;
+    scrpos_t x;
+    scrpos_t y;
+    dimm_t width;
+    dimm_t height;
+};
+
+int gfx_draw_shape(struct gfx_ctx *ctx, const struct gfx_shape *shape);
+
+__always_inline static inline size_t
+gfx_io_index(struct gfx_ctx *ctx, scrpos_t x, scrpos_t y)
+{
+    struct fbattr fbdev = ctx->fbdev;
+
+    return x + y * (fbdev.pitch  / 4);
+}
+
+#endif  /* !_LIBGFX_DRAW_H_ */
diff --git a/lib/libgfx/include/libgfx/gfx.h b/lib/libgfx/include/libgfx/gfx.h
new file mode 100644
index 0000000..3468571
--- /dev/null
+++ b/lib/libgfx/include/libgfx/gfx.h
@@ -0,0 +1,85 @@
+/*
+ * Copyright (c) 2023-2025 Ian Marco Moffett and the Osmora Team.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of Hyra nor the names of its
+ *    contributors may be used to endorse or promote products derived from
+ *    this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef _LIBGFX_H_
+#define _LIBGFX_H_
+
+#include <sys/fbdev.h>
+#include <stdint.h>
+#include <stdio.h>
+
+#define gfx_log(fmt, ...) printf( "libgfx: " fmt, ##__VA_ARGS__)
+
+/*
+ * Represents a 32-bit pixel value.
+ *
+ *   24:16  15:8  7:0
+ *  +-----------------+
+ *  | R  |   B   |  B |
+ *  +-----------------+
+ */
+typedef uint32_t pixel_t;
+typedef pixel_t color_t;
+
+/*
+ * Basic color defines
+ */
+#define GFX_BLACK   0x000000
+#define GFX_RED     0xFF0000
+#define GFX_GREEN   0x00FF00
+#define GFX_BLUE    0x0000FF
+#define GFX_WHITE   0xFFFFFF
+#define GFX_PURPLE  0x800080
+#define GFX_YELLOW  0xFFFF00
+
+/*
+ * Represents cartesian x/y values
+ */
+typedef uint32_t cartpos_t;
+typedef cartpos_t scrpos_t;
+typedef cartpos_t dimm_t;   /* Dimensions */
+
+/*
+ * Graphics context for libgfx
+ *
+ * @fbdev: Framebuffer attributes
+ * @io: Framebuffer pointer
+ * @fbfd: Framebuffer file descriptor
+ */
+struct gfx_ctx {
+    struct fbattr fbdev;
+    size_t fb_size;
+    pixel_t *io;
+    int fbfd;
+};
+
+int gfx_init(struct gfx_ctx *res);
+void gfx_cleanup(struct gfx_ctx *ctx);
+
+#endif  /* !_LIBGFX_H_ */
diff --git a/lib/libgfx/src/draw.c b/lib/libgfx/src/draw.c
new file mode 100644
index 0000000..49f2f53
--- /dev/null
+++ b/lib/libgfx/src/draw.c
@@ -0,0 +1,96 @@
+/*
+ * Copyright (c) 2023-2025 Ian Marco Moffett and the Osmora Team.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of Hyra nor the names of its
+ *    contributors may be used to endorse or promote products derived from
+ *    this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <sys/errno.h>
+#include <stdint.h>
+#include <libgfx/gfx.h>
+#include <libgfx/draw.h>
+
+/*
+ * Draw a classic square onto the screen.
+ *
+ * @ctx: Graphics context
+ * @shape: Square to draw
+ */
+static int
+gfx_draw_square(struct gfx_ctx *ctx, const struct gfx_shape *shape)
+{
+    struct fbattr fbdev;
+    off_t idx;
+    scrpos_t scr_width, scr_height;
+    scrpos_t x, y;
+
+    if (ctx == NULL || shape == NULL) {
+        return -EINVAL;
+    }
+
+    /* Grab screen dimensions */
+    fbdev = ctx->fbdev;
+    scr_width = fbdev.width;
+    scr_height = fbdev.height;
+
+    for (x = shape->x; x < shape->x + shape->width; ++x) {
+        for (y = shape->y; y < shape->y + shape->height; ++y) {
+            if (x >= scr_width || y >= scr_height) {
+                break;
+            }
+
+            idx = gfx_io_index(ctx, x, y);
+            ctx->io[idx] = shape->color;
+        }
+    }
+    return 0;
+}
+
+/*
+ * Draw a shape onto the screen
+ *
+ * @ctx: libgfx graphics context
+ * @shape: Shape to draw
+ *
+ * Returns 0 on success, otherwise a less than zero
+ * value on failure.
+ *
+ * All error codes follow POSIX errno. However if the value
+ * is -1, the requested shape to be drawn is not valid.
+ */
+int
+gfx_draw_shape(struct gfx_ctx *ctx, const struct gfx_shape *shape)
+{
+    if (ctx == NULL || shape == NULL) {
+        return -EINVAL;
+    }
+
+    switch (shape->type) {
+    case SHAPE_SQUARE:
+        return gfx_draw_square(ctx, shape);
+    }
+
+    return -1;
+}
diff --git a/lib/libgfx/src/gfx.c b/lib/libgfx/src/gfx.c
new file mode 100644
index 0000000..90dcb79
--- /dev/null
+++ b/lib/libgfx/src/gfx.c
@@ -0,0 +1,97 @@
+/*
+ * Copyright (c) 2023-2025 Ian Marco Moffett and the Osmora Team.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of Hyra nor the names of its
+ *    contributors may be used to endorse or promote products derived from
+ *    this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <sys/errno.h>
+#include <sys/mman.h>
+#include <sys/fbdev.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <libgfx/gfx.h>
+
+/*
+ * Initialize the libgfx context
+ *
+ * @res: Context pointer to be initialized
+ */
+int
+gfx_init(struct gfx_ctx *res)
+{
+    struct fbattr attr;
+    int fd, prot;
+
+    if (res == NULL) {
+        return -EINVAL;
+    }
+
+    /* Get framebuffer attributes */
+    fd = open("/ctl/fb0/attr", O_RDONLY);
+    if (fd < 0) {
+        gfx_log("could not open '/ctl/fb0/attr");
+        return fd;
+    }
+
+    read(fd, &attr, sizeof(attr));
+    close(fd);
+    res->fbdev = attr;
+
+    /* Open the framebuffer file */
+    res->fbfd = open("/dev/fb0", O_RDWR);
+    if (res->fbfd < 0) {
+        gfx_log("could not open '/dev/fb0'\n");
+        return res->fbfd;
+    }
+
+    /* Map the framebuffer into memory */
+    prot = PROT_READ | PROT_WRITE;
+    res->fb_size = attr.height * attr.pitch;
+    res->io = mmap(NULL, res->fb_size, prot, MAP_SHARED, res->fbfd, 0);
+
+    /* Did the mmap() call work? */
+    if (res->io == NULL) {
+        gfx_log("could not map framebuffer\n");
+        close(res->fbfd);
+        return -1;
+    }
+
+    return 0;
+}
+
+/*
+ * Cleanup all state and free the gfx
+ * context.
+ */
+void
+gfx_cleanup(struct gfx_ctx *ctx)
+{
+    if (ctx->io != NULL)
+        munmap(ctx->io, ctx->fb_size);
+    if (ctx->fbfd > 0)
+        close(ctx->fbfd);
+}