GLPaint白色背景 [英] GLPaint with white background

问题描述

我正在尝试通过逆向工程GLPaint在白色背景上绘制.我已经遍历了kSaturation，kLuminosity和glBlendFunc的每种组合，并且几乎可以想到画笔组合的每种组合(黑底白字，白底黑字，反面白字，别名/无别名等)，但是没有t偶然发现了想要的效果.

I'm trying draw on a white background by reverse engineering GLPaint. I've gone through every combination of kSaturation, kLuminosity and glBlendFunc, AND just about every combination I can think of for brush texture (black on white, white on black, white on trans, alias/no alias, etc), but haven't stumbled upon the desired effect.

我能达到的最好效果是使用反白变圆，以及glBlendFunc(GL_ SRC_ ALPHA，GL_ ONE_ MINUS_ SRC_ ALPHA)，但这仍然给我带来沉闷的色彩和半反色外部位被解释为黑色(即带黑色边缘的暗绿色，而不是带透明边缘的鲜绿色).好像它仍然假设我在黑色背景上.

The best I've been able to achieve is with a white-on-trans circle, with glBlendFunc (GL_ SRC_ ALPHA, GL_ ONE_ MINUS_ SRC_ ALPHA), but this still gives me a dull colour, and the semi-trans outer bits are interpreted as black (i.e. dull green with black edges, instead of vibrant green with transparent edges). It's as though it still assumes I'm on a black background.

有什么建议吗?

_{(来源: straandlooper.com )}

_{(source: straandlooper.com)}

推荐答案

我相信这是您希望它在White上可以使用的功能: glBlendFunc(GL_ONE，GL_ONE_MINUS_SRC_ALPHA);

I believe this is what you want for it to work on White: glBlendFunc(GL_ONE, GL_ONE_MINUS_SRC_ALPHA);

然后使用一个白色的'Particle.png'圆圈，使其逐渐透明(您的最佳"示例).

Then use a white 'Particle.png' circle that feathers out to transparency (your 'best' example).

这应该得到预期的结果.

This should give in the desired result.

这篇关于GLPaint白色背景的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！