March 2004 - Grx

Strange compile error in DevC++ & MinGW ?
by Peter Williams 31 Mar '04

31 Mar '04

I am using DevC++ & MinGW for GRX. If I have a defined constant 'white' (as a color index) then attempt to use GrWhite() a "parse error before numeric constant" is reported. E.g. #include <grx20.h> #include <grxkeys.h> #define white 0 GrColor White; int main(void) { GrSetMode(GR_default_graphics); White = GrWhite();/* gives "parse error before numeric constant" */ /* White = GrAllocColor(255,255,255); */ return(0); } If I remove my 'define' all is well, as is if I use GrAlloc instead of GrWhite. -- Peter Williams peter.williams173(a)ntlworld.com

3 2

Pascal types
by Frank Heckenbach 29 Mar '04

29 Mar '04

Hi, there are many bugs in the types in the Pascal interface (all the range from harmless to unportable to fatal). (I don't know what happened to them, since in an old version of grx.pas I got from somewhere, GrPattern was already correctly declared as a variant record, and in grx-2.4.6 it's wrong again ...) The attached patch should fix them, but I didn't test it extensively. So if someone else could have at look at them, I'd appreciate this. Frank -- Frank Heckenbach, frank(a)g-n-u.de http://fjf.gnu.de/ GnuPG and PGP keys: http://fjf.gnu.de/plan (7977168E)

1 0

Mailing list problems (March 20-23)
by Frank Heckenbach 28 Mar '04

28 Mar '04

Hallo, due to a problem when installing spam and virus filters, the mailing lists were out of order from last Saturday till Tuesday. Incoming mails were probably dropped without notice. If you sent any mail to the lists in this time, please check in the archives to find out if it got through, and otherwise please resend it. Sorry for the inconvenience, Frank -- Frank Heckenbach, frank(a)g-n-u.de, http://fjf.gnu.de/, 7977168E GPC To-Do list, latest features, fixed bugs: http://www.gnu-pascal.de/todo.html GPC download signing key: 51FF C1F0 1A77 C6C2 4482 4DDC 117A 9773 7F88 1707

1 0

Trouble with GrMouseWarp
by Peter Williams 17 Mar '04

17 Mar '04

Dear GRX I am reassured to hear that others have found difficulties with GrMouseWarp. I find that (under Win32) with the Gr_default_graphics, I can get GrMouseWarp to position itself correctly by adding 50 pixels to each of the x & y coordinates. However, I am sure that a new universal constant of nature has not been discovered. Something is not right... Also, I still can not get the mouse cursor to disappear. Peter Williams -- Pete Williams peter.williams173(a)ntlworld.com

4 3

problem using grx24 under djgppv2 with ati radeon 9600 graphic card.
by Je10bonjour＠aol.com 17 Mar '04

17 Mar '04

Hello, Using Grx24 (or greater) with djgppv2, the next problem appear under windows 98 or Xp when I use an Ati Radeon 9600 graphic card. In resolutions greater than 640x480, 256 colors or more, GrPixel or similaries orders that read the color of a portion of screen (GrBitBlt for example), give bad results. The portion that is read is often an other portion of the screen. The consequence is that the mouse erase all under it. It is thence impossible to use the mouse. The problem appear with the demogrx.exe for example, or with doing: mousetst 1024 768 256 , that test mouse in resolution 1024x768 256 colors. Is this a bug in grx or in the graphic card ? No problem using mingw and grx246 with the same graphic card. Thank you for the answer. Serge Cabala. P.S. I have done very good animations on waves using grx246. You can download these animations on my internet site htt://members.aol.com/scabala25 (site in french) . You can also find the site with Google for example, keywords : serge cabala

1 0

Trouble with GrMouseWarp
by Peter Williams 17 Mar '04

17 Mar '04

Dear GRX I have experienced trouble using GrMouseWarp under Win32(MinGW). Using it seems to position the cursor in the wrong place. Also, GrMouseErase does not seem to remove the cursor. I enclose a sample program. This draws a white cross at the centre. I then try and position the mouse cursor over it using GrMouseWarp. This seems to give the wrong position. Hiding it with GrMouseErase does not seem to work. I would be grateful of any advice. /* Program draws a white cross in the centre of the screen */ /* It then attempts to position the mouse at his point. */ /* Using GrMouseWarp(oX,oY) it attempts to match this point */ /* GrMouseEraseCursor() attempts to hide the mouse cursor */ /* Under Win32(MinGW) (W2000 & XP) it fails in these last two tasks */ /* Program is halted by a key press */ #include <stdio.h> #include <grx20.h> int main() { GrMouseEvent event; /*Mouse event */ int x,y,buttons; /* Mouse position & buttons */ int xMax,yMax,oX,oY; /* Size of screen & centre */ GrGraphicsMode gM; GrVideoAdapter gV; GrSetMode(GR_default_graphics); GrMouseInit(); /* In this order */ xMax = GrSizeX(); yMax = GrSizeY(); oX = xMax/2; oY = yMax/2; GrMouseWarp(oX,oY); GrMouseEraseCursor(); printf("xMax = %d yMax = %d\n",xMax,yMax); printf("oX = %d oY = %d\n",oX,oY); gM = GrCurrentMode(); printf("Graphics mode = %d\n",gM); gV = GrAdapterType(); printf("Video adapter = %d\n",gV); while(1) { GrMouseGetEvent(GR_M_MOTION,&event); GrLine(oX-4,oY,oX+4,oY,GrWhite()); GrLine(oX,oY-4,oX,oY+4,GrWhite()); if(GrKeyPressed()) break; } GrMouseUnInit(); return 0; } -- Pete Williams peter.williams173(a)ntlworld.com

2 1

Set an application icon
by Je10bonjour＠aol.com 16 Mar '04

16 Mar '04

Hello, Is it possible to set an application icon that will appear on the upper left screen using grx246 under mingw ? Is in grx246 an order similar to the GrSetWindowtitle, for the icon ? thank you. Serge Cabala.

1 0

Anti-aliased lines
by Ant Allen 15 Mar '04

15 Mar '04

Hi all, Has anyone ever implemented anti-aliased line-drawing into or on top of grx? If I use a standard algorithm for anti-aliased line drawing (eg http://courses.ece.uiuc.edu/ece291/archive/archive-f2000/mp/mp4/anti.html) with successive calls to GrDrawPixel will it be horribly slow? Ant --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com) Version: 6.0.622 / Virus Database: 400 - Release Date: 13/03/2004

1 0

Re: Problem cross-compiling with only framebuffer driver
by Josu Onandia 14 Mar '04

14 Mar '04

Hi, I cross-compile grx for an embedded system, too. I think that there is a mistake in the config files, and it always assumes that there is a svga hardware present. You can simply edit fdrivers\ftable.c and comment out the drivers you don't use, although it is more elegant if you: - make your own makefile (grx\src\makefile.custom) that is a copy of makefile.lnx. I don't like to modify the standard one - in this makefile add CCOPT += -DONLY_FRAMEBUFFER - in the file src\fdrivers\ftable.c replace the line #if !defined(__XWIN__) && !defined(__WIN32__) with #if !defined(__XWIN__) && !defined(__WIN32__) && !defined(ONLY_FRAMEBUFFER) I hope this helps. If it doesn't or you have more questions, don't hesitate to contact me privately. Josu Onandia > -----Mensaje original----- > De: Ant Allen [SMTP:aallen@race-technology.com] > Enviado el: jueves 11 de marzo de 2004 23:42 > Para: grx(a)gnu.de > Asunto: Problem cross-compiling with only framebuffer driver > > > Hi, > > I'm now trying to cross-compile grx for use on an embedded xscale > platform. > I'm using arm-linux-gcc 2.95.3. > > I've disabled svgalib and am compiling for the linux framebuffer with > makefile.lnx. > > The first problem I hit was libgrx.h referencing /sys/byteorder.h. This > seemed > to be asm related so I simply commented out that line in the source. > > Next problem is src/makefile.lnx lists various graphics drivers such as > ega.c > egavga.c etc etc. As I'm compiling for the framebuffer only I commented > these out in the makefile. > > Everything now seems to compile, but I get a problem when linking - see > below. > > Can anyone suggest a solution? > > Ideally I'd like to test out the cross-compilation with some either the > grx > demo or with the examples from the documentation. How far from this am I? > > All help greatly appreciated. > Ant > > make[1]: Entering directory `/usr/local/src/grx246/src' > arm-linux-gcc -c -O1 -Wall -DLFB_BY_NEAR_POINTER -pipe > -DFRAMEBUFFER_DRIVER > -I. -I./include -I../include utilprog/modetest.c -o utilprog/modetest.o > arm-linux-gcc -o ../bin/modetest utilprog/modetest.o > ../lib/unix/libgrx20.a > -lm > utilprog/modetest.o: In function `main': > utilprog/modetest.o(.text+0xf54): undefined reference to `GrKeyRead' > ../lib/unix/libgrx20.a(ftable.o)(.data+0x0): undefined reference to > `_GrFrameDriverEGAVGA1' > ../lib/unix/libgrx20.a(ftable.o)(.data+0x4): undefined reference to > `_GrFrameDriverEGA4' > ../lib/unix/libgrx20.a(ftable.o)(.data+0x8): undefined reference to > `_GrFrameDriverSVGA4' > ../lib/unix/libgrx20.a(ftable.o)(.data+0xc): undefined reference to > `_GrFrameDriverSVGA8' > ../lib/unix/libgrx20.a(ftable.o)(.data+0x10): undefined reference to > `_GrFrameDriverVGA8X' > ../lib/unix/libgrx20.a(ftable.o)(.data+0x14): undefined reference to > `_GrFrameDriverSVGA16' > ../lib/unix/libgrx20.a(ftable.o)(.data+0x18): undefined reference to > `_GrFrameDriverSVGA24' > ../lib/unix/libgrx20.a(ftable.o)(.data+0x1c): undefined reference to > `_GrFrameDriverSVGA32L' > ../lib/unix/libgrx20.a(ftable.o)(.data+0x20): undefined reference to > `_GrFrameDriverSVGA32H' > ../lib/unix/libgrx20.a(ftable.o)(.data+0x2c): undefined reference to > `_GrFrameDriverSVGA24_LFB' > ../lib/unix/libgrx20.a(ftable.o)(.data+0x30): undefined reference to > `_GrFrameDriverSVGA32L_LFB' > ../lib/unix/libgrx20.a(ftable.o)(.data+0x34): undefined reference to > `_GrFrameDriverSVGA32H_LFB' > ../lib/unix/libgrx20.a(ftable.o)(.data+0x48): undefined reference to > `_GrFrameDriverRAM24' > ../lib/unix/libgrx20.a(ftable.o)(.data+0x4c): undefined reference to > `_GrFrameDriverRAM32L' > ../lib/unix/libgrx20.a(ftable.o)(.data+0x50): undefined reference to > `_GrFrameDriverRAM32H' > collect2: ld returned 1 exit status > make[1]: *** [../bin/modetest] Error 1 > make[1]: Leaving directory `/usr/local/src/grx246/src' > make: *** [libs] Error 2 > >

2 1

grx-animation-problems
by Peter Williams 12 Mar '04

12 Mar '04

Dear GRX I read with interest the problems of Gernot Kleiter in mail #406 concering animation. As I newcomer to GRX I submit a very short double-buffering example: a rotating circle. Note by commenting out all the context & bitblt statements we arrive at a single buffered animation with flicker. I hope that this is useful. I am interested in the comments of fellow GRXites to improve this simple program. I run it under MinGW as I cannot get DJGPP to function on a W2000 laptop. /* This program animates a filled circle with double buffering */ /* The circle is red on a black background. The circle is of /* radius r and centre (x,y) which moves in a circular track of radius R */ /* centered in the middle of the screen */ #include <stdio.h> #include <math.h> #include <grx20.h> int main() { int x, y; /* centre coordinates */ int xMax,yMax; /* extent of the screen */ int Radius=100,r = 10; double Theta, dTheta,pi; /* Angle of rotation, increment and PI */ GrContext *memory,*screen; /* memory and screen contexts */ GrColor Red,Black; /* circle & background colours */ pi = 3.14159; dTheta = 0.5*pi/180.0; /* one half a degree increment */ Theta = 0.0; /* starting postion */ GrSetMode(GR_default_graphics ); xMax = GrMaxX(); yMax = GrMaxY(); Red = GrAllocColor(255,0,0); Black = GrBlack(); memory = GrCreateContext(xMax,yMax,NULL,NULL); screen = GrScreenContext(); while(1) /* run for ever! */ { x = xMax/2 + Radius*cos(Theta); /* circle centre */ y = yMax/2 + Radius*sin(Theta); Theta += dTheta; /* increment angle */ GrSetContext(memory); /* Set memory context */ GrClearContext(Black); /* Set context black */ GrFilledCircle(x,y,r,Red); /* draw red circle */ GrBitBlt(screen,0,0,memory,0,0,xMax-1,yMax-1,GrWRITE); /* copy to screen */ GrSetContext(screen); /* make visible */ } return 0; } -- Pete Williams peter.williams173(a)ntlworld.com

1 0