I'm having a problem with vcl styles overwriting custom colours. Is there a way to turn off styles when using onDrawItem, or detect when a style is on, and what the target colour will be?
Specifically, in this particular case, if the style is on the dark mode, text is made white, and in my case I need the background to be white. So white text against white background is invisible.
It looks like the pen color is being ignored and replaced with the style color, while background colors are correct.
Ideally, I'd like to ignore style stuff while in this particular draw routine, and just use my own colors. (Using C++Builder 11)
TIA
The code in question:
//TCheckListBox *clbxCategory;
void __fastcall TFormATB::clbxCategoryDrawItem(TWinControl* Control,
int Index, TRect &Rect, TOwnerDrawState State)
{
if(State.Contains(odSelected)) {
clbxCategory->Canvas->Pen->Color = clBlack;
clbxCategory->Canvas->Brush->Color = clActiveCaption;
clbxCategory->Canvas->RoundRect(Rect.Left, Rect.Top , Rect.Right, Rect.Bottom, 0, 50);
}
else {
clbxCategory->Canvas->Pen->Color = Colours[Index];
clbxCategory->Canvas->Brush->Color = Colours[Index];
}
clbxCategory->Canvas->Rectangle(Rect.Left, Rect.Top - 1, Rect.Right, Rect.Bottom + 1);
clbxCategory->Canvas->TextOut(Rect.Left, Rect.Top,clbxCategory->Items->Strings[Index]);
}
Related
I am working on a shader for Unity in which I want to change the color based on an mask image. In this mask image the RGB channels stand for a color that can be choosen in the shader. The idea behind the shader is that it is easy to change the look of an object without having to change the texture by hand.
Shader "Custom/MultiColor" {
Properties {
_MainTex ("Base (RGB)", 2D) = "white" {}
_MaskTex ("Mask area (RGB)", 2D) = "black" {}
_ColorR ("Red Color", Color) = (1,1,1,1)
_ColorG ("Green Color", Color) = (1,1,1,1)
_ColorB ("Blue Color", Color) = (1,1,1,1)
}
SubShader {
Tags { "RenderType"="Opaque" }
LOD 200
CGPROGRAM
#pragma surface surf Lambert
sampler2D _MainTex;
sampler2D _MaskTex;
half4 _ColorR;
half4 _ColorG;
half4 _ColorB;
half4 _MaskMult;
struct Input {
float2 uv_MainTex;
};
void surf (Input IN, inout SurfaceOutput o) {
half4 main = tex2D (_MainTex, IN.uv_MainTex);
half4 mask = tex2D (_MaskTex, IN.uv_MainTex);
half3 cr = main.rgb * _ColorR;
half3 cg = main.rgb * _ColorG;
half3 cb = main.rgb * _ColorB;
half r = mask.r;
half g = mask.g;
half b = mask.b;
half minv = min(r + g + b, 1);
half3 cf = lerp(lerp(cr, cg, g*(r+g)), cb, b*(r+g+b));
half3 c = lerp(main.rgb, cf, minv);
o.Albedo = c.rgb;
o.Alpha = main.a;
}
ENDCG
}
FallBack "Diffuse"
}
The problem with the shader is the blending between the masked color based on the green and blue channel. Between colors defined in the color supposted to be from the red region is visible. Below a sample is visable.
The red color is create by the red mask, green by the green mask and desert yellow by the blue region. I do not know why this happens or how to solve this problem.
Best guess: anti-aliasing or image compression. Aliasing (on the brush your using) will cause an overlap in the color channels, causing them to mix. Compression usually works by averaging each pixel's color info based on the colors around it (jpeg is especially notorious for this).
Troubleshoot by using a straight pixel based brush (no aliasing, no rounded edges) in Photoshop (or whatever image suite you're using) and/or try changing the colors through your shader and see how they mix- doing either should give you a better idea of what's going on under the hood. This combined with an lossless/uncompressed image-type, such as .tga should help, though they may use more memory.
I need to fill a rectangular region with semi-transparent color/brush in mfc. How can I achieve that?
You can't just fill a rectangle with a semi-transparent brush, you'll need to use something like AlphaBlend or TransparentBlt to create the effect.
An example is available here:
http://www.codeproject.com/Articles/286/Using-the-AlphaBlend-function
I found the solution. To fill the rectangle region with semi-transparent brush, we need to use GdiPlus objects.
Here is the Sample Code:
void FillSemiTransparentRegion(CDC *pDC, CRect rc)
{
if (pDC == NULL || rc.IsRectEmpty() || rc.IsRectNull())
return;
Graphics gr(pDC->GetSafeHdc());
SolidBrush br(Color(100, 0, 0, 0)); // Alpha, Red, Blue, Green
gr.FillRectangle(&br, rc.left, rc.right, rc.Width(), rc.Height());
}
I'm still extremely new to processing and I'm just playing around with it right now. I was hoping to find out how to change the background color between two colors, particularly between white and black, when I click my mouse. I found a code online that has the background color change between several different colors but I can't seem to figure out how the bg color can be changed between two colors. I would particularly like what 'col+=' and 'col%=' represent because I can't seem to find it in the processing tutorial. Please help me! Thank you!
Below is the code that I found.
void setup() {
size(600,400);
smooth();
colorMode(HSB);
}
int col = 0;
void draw() {
background(col,255,255);
}
void mousePressed(){
col+=20;
col%=255;
println(col);
}
"x += y" is shorthand for "x = x + y" and, likewise, "x %=y" is shorthand for "x = x % y" (where % is the modulo operator).
I'm going to assume that you wanted to ask is "how do I change the background from one colour to another, and then back again"; there's two basic ways to do this.
1: set up two (or more) reference colours, an extra "current" colour, and then change what 'current' points to, drawing the background off of that:
color c1 = color(255,0,0), c2 = color(0,0,255), current;
void setup() { current = c1; }
void draw() { background(current); }
void mousePressed() { if(current==c1) { current = c2; } else { current = c1; }}
Every time you click, the program checks which of the two colours "current" points to, and then instead points it to the other colour.
2: set up one colour, and apply some operation that is modulo in 1, or 2, or ... steps:
color c = color(255,0,0);
void draw() { background(c); }
void mousePressed() { c = color( red(c), (green(c)+50)%255, blue(c)); }
Every time you click, the colour "c" gets its green component increased by 50, and then modulo-corrected for 255. So it'll cycle through: 0, 50, 100, 150, 200, 250, 300%255=45, 95, 145, 195, 245, 295%255=40, 90, etc.
While the question title seems dumb, that's not exactly what I need. To fill whole area with color, one needs to select appropriate brush - that's trivial. But I want to fill upper half of it with different color, and bottom half of it with the different one. If it was the normal (not round) rectangle, I could draw two rectangles (with different brushes). But with RoundRect I don't have any ideas how to do it.
Here is what I need it for: I draw each node in my graph visualization with RoundRect, and those nodes should have several compartments (cells) that should be filled with different colors.
I hope you get the idea what I mean :)
If you have to use legacy GDI instead of GDI+, here I wrote you a function to draw such a (cell) as you needed I hope it is what you have expected !
The basic idea is to create upper and lower regions (which they were both full overlapping rounded rectangles, then each has one of its halves cut off)
I have prepared the above illustration to show how the cell could be produced. It's for the upper side only, but you should have got the idea of creating the lower one.
Here is a wrapping function to create the cell you need:
void DrawCell(HDC& hdc, const RECT& rcTarget,const HBRUSH& hbrUpper, const HBRUSH& hbrLower)
{
HRGN hRgnUpper = CreateRoundRectRgn(rcTarget.left, rcTarget.top, rcTarget.right, rcTarget.bottom, 42, 38);
HRGN hRgnLower = CreateRoundRectRgn(rcTarget.left, rcTarget.top, rcTarget.right, rcTarget.bottom, 42, 38);
HRGN hRgnCutFromUpper = CreateRectRgn(rcTarget.left, rcTarget.top + ((rcTarget.bottom - rcTarget.top) / 2), rcTarget.right, rcTarget.bottom);
HRGN hRgnCutFromLower = CreateRectRgn(rcTarget.left, rcTarget.top , rcTarget.right, rcTarget.bottom - ((rcTarget.bottom - rcTarget.top) / 2));
CombineRgn(hRgnUpper, hRgnUpper,hRgnCutFromUpper, RGN_DIFF);
CombineRgn(hRgnLower, hRgnLower,hRgnCutFromLower, RGN_DIFF);
FillRgn( hdc, hRgnUpper, hbrUpper);
FillRgn( hdc, hRgnLower, hbrLower);
DeleteObject(hRgnCutFromLower);
DeleteObject(hRgnCutFromUpper);
DeleteObject(hRgnLower);
DeleteObject(hRgnUpper);
}
call this function from within your WM_PAINT handler:
RECT rcTarget;
rcTarget.left = 20;
rcTarget.top = 20;
rcTarget.right = 275;
rcTarget.bottom = 188;
HBRUSH hRed = CreateSolidBrush( RGB(255, 0, 0) );
HBRUSH hGreen = CreateSolidBrush( RGB(0, 255, 0) );
DrawCell(hdc, rcTarget, hRed, hGreen);
I've got a little text drawing puzzle under Win32. I'm trying to draw some instructions for users of my application at the top of the window.
Please refer to the following window (I've changed the background color on the text so you can see the boundaries)
(source: billy-oneal.com)
I'm currently using DrawTextEx to draw the text to my window, but the problem is that it does not fill the entire RECTangle that I give it. Not drawing that area is just fine, until the window resizes:
(source: billy-oneal.com)
When the text is re wrapped due to the window sizing, because DrawTextEx doesn't clear it's background, these artifacts are leftover.
I tried using FillRect to fill in the area behind the text drawing call, which does eliminate the visual artifacts, but then causes the text to flicker constantly, as it is completely erased and then completely redrawn to the display.
Any ideas on how one might get the area not containing text to be drawn with the background color?
EDIT: I'd like to avoid having to double buffer the form if at app possible.
EDIT2: I solved the problem by only redrawing the text when I detect that the wrapping changes during a resize.
Use double buffering?
Draw everything to a bitmap and draw the bitmap to the window. Flickering is commonly a double buffering issue.
There are many possible solutions and without seeing your code, it's hard to tell which method would be best so I'd suggest taking a look at this article on flicker free drawing
SetBkMode + SetBkColor ?
Well since nobody seems to know what to do about it, I implemented it this way:
std::vector<std::wstring> wrapString(HDC hDC, const std::wstring& text, const RECT& targetRect, HFONT font)
{
std::vector<std::wstring> result;
RECT targetRectangle;
CopyRect(&targetRectangle, &targetRect);
//Calculate the width of the bounding rectangle.
int maxWidth = targetRectangle.right - targetRectangle.left;
//Draw the lines one at a time
std::wstring currentLine;
for(std::wstring::const_iterator it = text.begin(); it != text.end(); currentLine.push_back(*it), it++)
{
if(*it == L'\r' || *it == L'\n')
{ //Hard return
while(it != text.end() && (*it == L'\r' || *it == L'\n')) it++;
result.push_back(currentLine);
currentLine.clear();
}
else
{ //Check for soft return
SIZE sizeStruct;
GetTextExtentPoint32(hDC, currentLine.c_str(), static_cast<int>(currentLine.length()), &sizeStruct);
if (sizeStruct.cx > maxWidth)
{
std::wstring::size_type lineLength = currentLine.find_last_of(L' ');
if (lineLength == currentLine.npos)
{ //Word is longer than a line.
for(;it != text.end() && !iswspace(*it);it++) currentLine.push_back(*it);
}
else
{ //Clip word to line.
//Backtrack our scan of the source text.
it -= currentLine.length() - lineLength - 1;
//Remove the clipped word
currentLine.erase(lineLength);
}
result.push_back(currentLine);
currentLine.clear();
}
}
}
//Last remaining text.
result.push_back(currentLine);
return result;
}
void DrawInstructionsWithFilledBackground(HDC hDC, const std::wstring& text, RECT& targetRectangle, HFONT font, COLORREF backgroundColor)
{
//Set up our background color.
int dcIdx = SaveDC(hDC);
HBRUSH backgroundBrush = CreateSolidBrush(backgroundColor);
SelectObject(hDC, backgroundBrush);
SelectObject(hDC, font);
SetBkColor(hDC, backgroundColor);
std::vector<std::wstring> lines(wrapString(hDC, text, targetRectangle, font));
for(std::vector<std::wstring>::const_iterator it = lines.begin(); it!=lines.end(); it++)
{
RECT backgroundRect = targetRectangle;
DrawText(hDC, const_cast<LPWSTR>(it->c_str()), static_cast<int>(it->length()), &backgroundRect, DT_CALCRECT | DT_NOCLIP | DT_SINGLELINE);
backgroundRect.left = backgroundRect.right;
backgroundRect.right = targetRectangle.right;
if (backgroundRect.right >= backgroundRect.left)
FillRect(hDC, &backgroundRect, backgroundBrush);
ExtTextOut(hDC, targetRectangle.left, targetRectangle.top, ETO_OPAQUE, NULL, it->c_str(), static_cast<UINT>(it->length()), NULL);
targetRectangle.top += backgroundRect.bottom - backgroundRect.top;
}
instructionsWrap = lines;
//Restore the DC to it's former glory.
RestoreDC(hDC, dcIdx);
DeleteObject(backgroundBrush);
}
Get/Calculate the rect used by the DrawText call and clip it with something like ExcludeClipRect before calling FillRect