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shmx wrote:If only the text, then it is very simple.

octacone wrote:The problem is: getting pixels from selected region.

shmx wrote:

octacone wrote:The problem is: getting pixels from selected region.

It is simply copying memory. I do not understand what could be the problem.

unsigned location = (position.Y * screenWidthBGA * 4) + (position.X * 4);
	linearFrameBufferBGA[location + 0] = 0;
	linearFrameBufferBGA[location + 2] = color.R;
	linearFrameBufferBGA[location + 1] = color.G;
	linearFrameBufferBGA[location + 0] = color.B;

octacone wrote:How is it simple and why do you keep referring to the text. Remember in this case: text = just pixels.

octacone wrote:I don't know how to get specific pixels from wanted location.

DWORD GetPixel32(int X, int Y)
{
     DWORD *v_mem = (DWORD *)VideoMemory;
     return v_mem[X + Y * ScreenPithInPixels];
}

octacone wrote:I don't know how to get specific pixels from wanted location.

DWORD SetPixel32(int X, int Y, DWORD Color)
{
     DWORD *v_mem = (DWORD *)VideoMemory;
    v_mem[X + Y * ScreenPithInPixels] = Color;
}
#define MAKE_RGB(r, g, b) ( ( ((DWORD)r) << 16 ) | ( ((DWORD)g) << 8 ) |  ( ((DWORD)b) << 0 ) )
#define GET_R(color) ( (color >> 16) & 0xFF)
#define GET_G(color) ( (color >> 8) & 0xFF)
#define GET_B(color) ( (color >> 0) & 0xFF)

shmx wrote:

octacone wrote:I don't know how to get specific pixels from wanted location.

It is an inefficient way.

Code: Select all

DWORD SetPixel32(int X, int Y, DWORD Color)
{
     DWORD *v_mem = (DWORD *)VideoMemory;
    v_mem[X + Y * ScreenPithInPixels] = Color;
}
#define MAKE_RGB(r, g, b) ( ( ((DWORD)r) << 16 ) | ( ((DWORD)g) << 8 ) |  ( ((DWORD)b) << 0 ) )
#define GET_R(color) ( (color >> 16) & 0xFF)
#define GET_G(color) ( (color >> 8) & 0xFF)
#define GET_B(color) ( (color >> 0) & 0xFF)

But it is better to avoid the functions (get)setpixel. This is just an example of work with video memory. It is better to draw the primitives directly (it is a bit more complicated).

shmx wrote:

octacone wrote:I don't know how to get specific pixels from wanted location.

Code: Select all

DWORD GetPixel32(int X, int Y)
{
     DWORD *v_mem = (DWORD *)VideoMemory;
     return v_mem[X + Y * ScreenPithInPixels];
}

???

max wrote:Hey, please don't create a new post everytime you want to add something. Edit your previous post.

octacone wrote:

max wrote:Hey, please don't create a new post everytime you want to add something. Edit your previous post.

I know. Just trying to bring some attention over here.

Okay lets make it simple:
How do I capture 1600x900x32 area of pixels, save those pixels to a buffer and shift their y coordinate by wanted amount?

Ch4ozz wrote:

octacone wrote:

max wrote:Hey, please don't create a new post everytime you want to add something. Edit your previous post.

I know. Just trying to bring some attention over here.

Okay lets make it simple:
How do I capture 1600x900x32 area of pixels, save those pixels to a buffer and shift their y coordinate by wanted amount?

I already gave you the complete memcpy 2 liner in my previous post which solves your problem (even though you should REALLY save the text AND the pixels in 2 different buffers so you can REDRAW text INSTEAD of copying pixels)
Re-read my post and think about your answer (which makes no sense because your buffer is a linear frame buffer exactly like mine)

octacone wrote:That is unsigned long right?
VideoMemory = my linear frame buffer