Can set individual pixels of your screen, draw lines with gradients, draw rectangles and triangles. set vertex's colors and interpolate to shade. Loop them to animate. Plot data with pixel precision. The possibilities are endless with Fortran.
may need to make yourself part of the 'video' group to write to '/dev/fb0'
fbMod1.f90 has routines draw only to the framebuffer
fbMod2.f90 has routines that draw to a PixBuffType and routines for getting and putting these
types into other types.
-fbhello.f90
does not use fbMod.f90 but uses the basic elements to make a simple demonstration.
-fbtest.f90
demonstrates most of the routines
-fbbuffertest.f90
tests the use of the User Buffer, this is the fastest way to repeatedly draw frames to the screen.
-colors.f90
draws a colorwheel out of six triangles.. not really a circle.
-colorPicker.f90
interactive selection of Hue, Saturation and Value and conversion to RGB.
-heatdiff.f90
demonstrates 2d transient thermal diffusion, displayed in real time.
-fbplot.f90
not just a demo program:
fbplot -- Plot data from columns of file to the framebuffer device /dev/fb0
Usage:
fbplot xcol ycol y2col y3col ... yNcol FILE
xcol is the column of FILE to use as x coordinates
ycol is the column of FILE to use as the first dependent variable
subsequent integer arguments are interpreted as additional dependent variables
to plot onto the same plot.
FILE is the last argument and is the file path
an interactive program that loads PPM files for editting. It supports many of these drawing routines and can save user edits as PPM.
controls use vim like motion: hjkl, with HJKL movement by 10px. Type the first letter of the buttons on the left to enter operation mode. indicated by the name at the bottom of the image. press ESC to abort the operation. Space to select points. Capital letters indicate filled shapes: So 'r' is a rectangular outline, while 'R' is a filled rectangle. Colors are selected based on their number, and the upper color rows by pressing SHIFT+#. Edit the currently selected color with '+', will open a color choosing window. Press enter to select the color. use TAB to change between H,S, and V bars. Use K,k,j,J to move selectors up and down.
-fb_init(i,dev, mode, wd,ht,ln, zbu)
set variables and open framebuffer device
i file descriptor
dev device path of framebuffer, usually /dev/fb0
mode can be direct to device or written to a buffer to be dumped later
wd pixel width of framebuffer device
ht pixel height of framebuffer device
ln pixel line length of framebuffer device
zbu use a Z-Buffer?
-fb_write
dumps the user buffer to the fb device.
-fb_read
reads the current device buffer into the user buffer.
-fb_dump(FL,mode)
writes the user buffer to file descriptor FL
mode 1: raw dump 2: PPM 3: X,Y, R,G,B list
-fb_close
closes the framebuffer device file
-getrec(x,y)
returns the 4Byte record number for an XY screen position or the byte offset in "buffer" mode.
-fb_pixel(x,y,px)
set pixel px at location (x,y).
-fb_clear(b)
fills the buffer with byte value b. default is NULL.
-PointSlope(i,x1,y1,x2,y2)
point slope form of line. returns y given an x that falls on a line from point 1 to 2.
-fb_filltriangle( x1, y1, x2, y2, x3, y3, px )
Draw a filled triangle with verticies p1, p2, p3 with color, px
-fb_filltriangle3c( x1,y1, x2,y2, x3,y3, px1,px2,px3, sb, z1,z2,z3 )
Draw a filled trianlge with verticies p1, p2, p3.
each vertex has color px1, px2, px3, fill colour interpolates within bounds, sb.
Z values optional and operate if zbu was set to true, for correct layering.
-fb_line(x1,y1,x2,y2,px)
Draw a line from point to point to the terminal directly, using the Bresenham algorithm
-fb_line2c(x1,y1,x2,y2,px1,px2,sb,z1,z2)
Draw a line from point to point to the terminal directly with colors px1, px2.
using the Bresenham algorithm and 'sb' to check bounds.
-fb_rec(x1,y1,x2,y2,px)
Draw a rectangle from top left point to bottom right point to the terminal directly
-fb_linepolar(x,y,r,theta,px)
Draw a line from point with radius and angle to the terminal directly. Angle in degrees
-fb_circle( x, y, r, px )
draw a circle centered at location (x,y) with radius of, r. and color, px
-fb_plot( XY, pr, sr, px )
plot data XY within the plot range pr into a pixel domain sr
-fb_mplot( XY, pr, sr, px )
plot multiple data XY within the plot range pr into a pixel domain sr
-fb_heatplot( XYZ, pr, sr, cr )
plot data XYZ within plot range pr into pixel domain sr, color range: cr=(bw,rgb)
-fb_matrixplot( XYZ, ar, sr, cr )
plot data XYZ within amplitude range ar into pixel domain sr, color range: cr=(bw,rgb)
-fb_printNumber(n, x, y, s, px, bpx)
print a monochrome digit, n, at location, x, y, with size, s, and color, px.
-fb_printString(str, x, y, s, px, bpx)
print a monochrome alphastring, str, at location, x, y, with size, s, and color, px.