From 8c4be7ea70f5d5df32ca3e7a007240b62a7b9573 Mon Sep 17 00:00:00 2001
From: "arnau.nau" <a@rnau.me>
Date: Sat, 25 Jan 2025 23:09:02 +0100
Subject: [PATCH] [Renderers/SDL3] Fix corner thickness draw direction +
artifacts on large thickness values.
---
renderers/SDL3/clay_renderer_SDL3.c | 56 +++++++++++++++++------------
1 file changed, 34 insertions(+), 22 deletions(-)
diff --git a/renderers/SDL3/clay_renderer_SDL3.c b/renderers/SDL3/clay_renderer_SDL3.c
index 63346a3..91ef025 100644
--- a/renderers/SDL3/clay_renderer_SDL3.c
+++ b/renderers/SDL3/clay_renderer_SDL3.c
@@ -118,16 +118,20 @@ static void SDL_RenderArc(SDL_Renderer *renderer, const SDL_FPoint center, const
const float radStart = startAngle * (SDL_PI_F / 180.0f);
const float radEnd = endAngle * (SDL_PI_F / 180.0f);
- const int numCircleSegments = SDL_max(NUM_CIRCLE_SEGMENTS, (int)(radius * 0.5f));
+ const int numCircleSegments = SDL_max(NUM_CIRCLE_SEGMENTS, (int)(radius * 1.5f)); //increase circle segments for larger circles, 1.5 is arbitrary.
- const float angleStep = (radEnd - radStart) / numCircleSegments;
- const float halfThickness = thickness * 0.5f;
- for (float t = -halfThickness; t < halfThickness-0.5f; t += 0.5f) {
+ const float angleStep = (radEnd - radStart) / (float)numCircleSegments;
+ const float thicknessStep = 0.4f; //arbitrary value to avoid overlapping lines. Changing THICKNESS_STEP or numCircleSegments might cause artifacts.
+
+ for (float t = thicknessStep; t < thickness - thicknessStep; t += thicknessStep) {
SDL_FPoint points[numCircleSegments + 1];
+ const float clampedRadius = SDL_max(radius - t, 1.0f);
for (int i = 0; i <= numCircleSegments; i++) {
const float angle = radStart + i * angleStep;
- points[i] = (SDL_FPoint){ center.x + SDL_cosf(angle) * (radius + t), center.y + SDL_sinf(angle) * (radius + t) };
+ points[i] = (SDL_FPoint){
+ SDL_roundf(center.x + SDL_cosf(angle) * clampedRadius),
+ SDL_roundf(center.y + SDL_sinf(angle) * clampedRadius) };
}
SDL_RenderLines(renderer, points, numCircleSegments + 1);
}
@@ -176,50 +180,58 @@ static void SDL_RenderClayCommands(SDL_Renderer *renderer, Clay_RenderCommandArr
.bottomRight = SDL_min(config->cornerRadius.bottomRight, minRadius)
};
//edges
+ SDL_SetRenderDrawColor(renderer, config->left.color.r, config->left.color.g, config->left.color.b, config->left.color.a);
if (config->left.width > 0) {
- const float starting_y = rect.y + (float)clampedRadii.topLeft;
- const float length = rect.h - (float)clampedRadii.topLeft - (float)clampedRadii.bottomLeft;
+ const float starting_y = rect.y + clampedRadii.topLeft;
+ const float length = rect.h - clampedRadii.topLeft - clampedRadii.bottomLeft;
SDL_FRect line = { rect.x, starting_y, config->left.width, length };
- SDL_SetRenderDrawColor(renderer, config->left.color.r, config->left.color.g, config->left.color.b, config->left.color.a);
SDL_RenderFillRect(renderer, &line);
}
if (config->right.width > 0) {
const float starting_x = rect.x + rect.w - (float)config->right.width;
- const float starting_y = rect.y + (float)clampedRadii.topRight;
- const float length = rect.h - (float)clampedRadii.topRight - (float)clampedRadii.bottomRight;
+ const float starting_y = rect.y + clampedRadii.topRight;
+ const float length = rect.h - clampedRadii.topRight - clampedRadii.bottomRight;
SDL_FRect line = { starting_x, starting_y, config->right.width, length };
SDL_RenderFillRect(renderer, &line);
}
if (config->top.width > 0) {
- const float starting_x = rect.x + (float)clampedRadii.topLeft;
- const float length = rect.w - (float)clampedRadii.topLeft - (float)clampedRadii.topRight;
+ const float starting_x = rect.x + clampedRadii.topLeft;
+ const float length = rect.w - clampedRadii.topLeft - clampedRadii.topRight;
SDL_FRect line = { starting_x, rect.y, length, config->top.width };
SDL_RenderFillRect(renderer, &line);
}
if (config->bottom.width > 0) {
- const float starting_x = rect.x + (float)clampedRadii.bottomLeft;
+ const float starting_x = rect.x + clampedRadii.bottomLeft;
const float starting_y = rect.y + rect.h - (float)config->bottom.width;
- const float length = rect.w - (float)clampedRadii.bottomLeft - (float)clampedRadii.bottomRight;
+ const float length = rect.w - clampedRadii.bottomLeft - clampedRadii.bottomRight;
SDL_FRect line = { starting_x, starting_y, length, config->bottom.width };
SDL_SetRenderDrawColor(renderer, config->bottom.color.r, config->bottom.color.g, config->bottom.color.b, config->bottom.color.a);
SDL_RenderFillRect(renderer, &line);
}
//corners
if (config->cornerRadius.topLeft > 0) {
- SDL_RenderArc(renderer, (SDL_FPoint){rect.x + clampedRadii.topLeft, rect.y + clampedRadii.topLeft},
- clampedRadii.topLeft, 180.0f, 270.0f, config->top.width, config->top.color);
+ const float centerX = rect.x + clampedRadii.topLeft -1;
+ const float centerY = rect.y + clampedRadii.topLeft;
+ SDL_RenderArc(renderer, (SDL_FPoint){centerX, centerY}, clampedRadii.topLeft,
+ 180.0f, 270.0f, config->top.width, config->top.color);
}
if (config->cornerRadius.topRight > 0) {
- SDL_RenderArc(renderer, (SDL_FPoint){rect.x + rect.w - clampedRadii.topRight - config->right.width, rect.y + clampedRadii.topRight},
- clampedRadii.topRight, 270.0f, 360.0f, config->top.width, config->top.color);
+ const float centerX = rect.x + rect.w - clampedRadii.topRight -1;
+ const float centerY = rect.y + clampedRadii.topRight;
+ SDL_RenderArc(renderer, (SDL_FPoint){centerX, centerY}, clampedRadii.topRight,
+ 270.0f, 360.0f, config->top.width, config->top.color);
}
if (config->cornerRadius.bottomLeft > 0) {
- SDL_RenderArc(renderer, (SDL_FPoint){rect.x + clampedRadii.bottomLeft, rect.y + rect.h - clampedRadii.bottomLeft - config->bottom.width},
- clampedRadii.bottomLeft, 90.0f, 180.0f, config->bottom.width, config->bottom.color);
+ const float centerX = rect.x + clampedRadii.bottomLeft -1;
+ const float centerY = rect.y + rect.h - clampedRadii.bottomLeft -1;
+ SDL_RenderArc(renderer, (SDL_FPoint){centerX, centerY}, clampedRadii.bottomLeft,
+ 90.0f, 180.0f, config->bottom.width, config->bottom.color);
}
if (config->cornerRadius.bottomRight > 0) {
- SDL_RenderArc(renderer, (SDL_FPoint){rect.x + rect.w - clampedRadii.bottomRight - config->left.width, rect.y + rect.h - clampedRadii.bottomRight - config->bottom.width},
- clampedRadii.bottomRight, 0.0f, 90.0f, config->bottom.width, config->bottom.color);
+ const float centerX = rect.x + rect.w - clampedRadii.bottomRight -1; //TODO: why need to -1 in all calculations???
+ const float centerY = rect.y + rect.h - clampedRadii.bottomRight -1;
+ SDL_RenderArc(renderer, (SDL_FPoint){centerX, centerY}, clampedRadii.bottomRight,
+ 0.0f, 90.0f, config->bottom.width, config->bottom.color);
}
} break;