putpixel fast...

[relo]

the display->buffer.PutPixel(i,t,E_RGBX(250,250,250)); so slow.

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1  2  3  4  5  6  7  8  9	E2DSURFACEINFO sf_inf;     unsigned char* Video_Buffer=display->buffer.Lock(&sf_inf);    for (int i=0;i<100;i++)         for (int t=0;t<100;t++)     //display->buffer.PutPixel(i,t,E_RGBX(250,250,250));             Video_Buffer[i+t*sf_inf.width]=E_RGBX(250,250,250);    display->buffer.Unlock();
	9 lines; 6 keywds; 7 nums; 43 ops; 0 strs; 1 coms    Syntactic Coloring v0.4 - Dan East

The given code works not correctly (draws small 10х10 squares instead of one big 100х100).

How it is possible to draw points quickly?

Thanks.

[edge]

Hi Relo,

Locking the backbuffer is the fastest way to plot pixels. Make sure to use the xpitch and ypitch members of the E2DSURFACEINFO structure.

For example:

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1	videobuffer[x * xpitch + y * ypitch] = 0;
	1 lines; 0 keywds; 1 nums; 7 ops; 0 strs; 0 coms    Syntactic Coloring v0.4 - Dan East

When locking the backbuffer be sure to check the pixelformat of the surface, not all devices have the same colordepth.

[relo]

Thanks. So works. But it is not absolutely correct always plot pixels - blue color, and should be red.
Video_Buffer[х * xpitch + y * ypitch]=E_RGBX(255,0,0);

PixelFormat - 6 ??

How to me to deduce pixels of red color (for an example)?

[edge]

Hi Relo,

The E_RGBX macro shouldn't be used when plotting pixels directly. Here is a piece of sample code to plot a pixel and handle the several colordepths (assuming the red, green and blue values go from 0 to 255):

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1  2  3  4  5  6  7  8  9  10  11  12

switch(pixelformat) {     case EDSP_TRUE12:         Video_Buffer[x * xpitch + y * ypitch]=((red & 0xF0) << 4) | (green & 0xF0) | ((blue & 0xF0) >> 4);         break;     case EDSP_TRUE16:         Video_Buffer[x * xpitch + y * ypitch]=((red & 0xF8) << 8) | ((green & 0xFC) << 3) | ((blue & 0xF8) >> 3);         break;     case EDSP_TRUE32:         Video_Buffer[x * xpitch + y * ypitch]=(red << 16) | (green << 8) | blue;         break; }

12 lines; 7 keywds; 13 nums; 83 ops; 0 strs; 0 coms    Syntactic Coloring v0.4 - Dan East

More information about the pixel formats:
For Windows Desktop the most commonly used format is EDSP_TRUE32, unless it's set to 16-bit colors in the display configuration. On Windows Mobile EDSP_TRUE16 is used, but there is a big chance that EDSP_TRUE32 is used as well or will be used in the future. For Symbian it uses all three, although EDSP_TRUE12 is used in old devices (for example, Nokia N-Gage).

[relo]

Strange works. Now draws always yellow points.
(I test on "Windows Desktop" - Video_Buffer[x * xpitch + y * ypitch]=(red << 16) | (green << | blue; ) .....

[edge]

Hi Relo,

Are you initializing your variables? For example:

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1  2  3	red = 255; green = 0; blue = 0;
	3 lines; 0 keywds; 3 nums; 6 ops; 0 strs; 0 coms    Syntactic Coloring v0.4 - Dan East

[relo]

yes.

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1  2  3  4  5  6  7	unsigned long CC,red,green,blue;       red=0;     green=255;     blue=0;     CC=(red << 16 ) | (green << 8 ) | blue;       ...............       Video_Buffer[i * sf_inf.xpitch + t * sf_inf.ypitch]=CC;
	7 lines; 2 keywds; 5 nums; 46 ops; 0 strs; 0 coms    Syntactic Coloring v0.4 - Dan East

And if to draw on a background, such sensation what to be put the color filter (all to become with a shade yellow)

Probably one byte of all changes in memory ?

[edge]

Hi Relo,

It probably doesn't work because you're using an unsigned char * pointer for accessing the display memory. For EDSP_TRUE32 you need to cast it to unsigned long:

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1	unsigned long *videomem32 = (unsigned long *)Video_Buffer;
	1 lines; 4 keywds; 0 nums; 6 ops; 0 strs; 0 coms    Syntactic Coloring v0.4 - Dan East

For EDSP_TRUE12 and EDSP_TRUE16 use unsigned short.