From 35a9d156a6fb113ab9621cb4b17865249a00df7e Mon Sep 17 00:00:00 2001
From: Marcin Serwin <[EMAIL REDACTED]>
Date: Sun, 8 Dec 2024 12:08:58 +0100
Subject: [PATCH] render: convert tmotion vectors to render basis
When using `SDL_ConvertEventToRenderCoordinates` with
`SDL_EVENT_FINGER_MOTION` events it converts `x` and `y` coordinates but
does not convert the the `dx` and the `dy` unlike `xrel` and `yrel` of
mouse motion events. This is means that these are rather useless after
conversion. This change unifies this behavior between touch and mouse
motion events.
---
src/render/SDL_render.c | 56 ++++++++++++++++++-----------------------
1 file changed, 25 insertions(+), 31 deletions(-)
diff --git a/src/render/SDL_render.c b/src/render/SDL_render.c
index 1138464cad22a..6e8c7ad33fa2d 100644
--- a/src/render/SDL_render.c
+++ b/src/render/SDL_render.c
@@ -2788,6 +2788,29 @@ static void SDL_RenderLogicalPresentation(SDL_Renderer *renderer)
}
}
+static bool SDL_RenderVectorFromWindow(SDL_Renderer *renderer, float window_dx, float window_dy, float *restrict dx, float *restrict dy)
+{
+ // Convert from window coordinates to pixels within the window
+ window_dx *= renderer->dpi_scale.x;
+ window_dy *= renderer->dpi_scale.y;
+
+ // Convert from pixels within the window to pixels within the view
+ if (renderer->logical_presentation_mode != SDL_LOGICAL_PRESENTATION_DISABLED) {
+ const SDL_FRect *src = &renderer->logical_src_rect;
+ const SDL_FRect *dst = &renderer->logical_dst_rect;
+ window_dx = (window_dx * src->w) / dst->w;
+ window_dy = (window_dy * src->h) / dst->h;
+ }
+
+ const SDL_RenderViewState *view = &renderer->main_view;
+ window_dx /= view->scale.x;
+ window_dy /= view->scale.y;
+
+ *dx = window_dx;
+ *dy = window_dy;
+ return true;
+}
+
bool SDL_RenderCoordinatesFromWindow(SDL_Renderer *renderer, float window_x, float window_y, float *x, float *y)
{
float render_x, render_y;
@@ -2856,37 +2879,7 @@ bool SDL_ConvertEventToRenderCoordinates(SDL_Renderer *renderer, SDL_Event *even
SDL_Window *window = SDL_GetWindowFromID(event->motion.windowID);
if (window == renderer->window) {
SDL_RenderCoordinatesFromWindow(renderer, event->motion.x, event->motion.y, &event->motion.x, &event->motion.y);
-
- if (event->motion.xrel != 0.0f) {
- // Convert from window coordinates to pixels within the window
- float scale = renderer->dpi_scale.x;
-
- // Convert from pixels within the window to pixels within the view
- if (renderer->logical_presentation_mode != SDL_LOGICAL_PRESENTATION_DISABLED) {
- const SDL_FRect *src = &renderer->logical_src_rect;
- const SDL_FRect *dst = &renderer->logical_dst_rect;
- scale = (scale * src->w) / dst->w;
- }
-
- // Convert from pixels within the view to render coordinates
- scale = (scale / renderer->main_view.scale.x);
- event->motion.xrel *= scale;
- }
- if (event->motion.yrel != 0.0f) {
- // Convert from window coordinates to pixels within the window
- float scale = renderer->dpi_scale.y;
-
- // Convert from pixels within the window to pixels within the view
- if (renderer->logical_presentation_mode != SDL_LOGICAL_PRESENTATION_DISABLED) {
- const SDL_FRect *src = &renderer->logical_src_rect;
- const SDL_FRect *dst = &renderer->logical_dst_rect;
- scale = (scale * src->h) / dst->h;
- }
-
- // Convert from pixels within the view to render coordinates
- scale = (scale / renderer->main_view.scale.y);
- event->motion.yrel *= scale;
- }
+ SDL_RenderVectorFromWindow(renderer, event->motion.xrel, event->motion.yrel, &event->motion.xrel, &event->motion.yrel);
}
} else if (event->type == SDL_EVENT_MOUSE_BUTTON_DOWN ||
event->type == SDL_EVENT_MOUSE_BUTTON_UP) {
@@ -2912,6 +2905,7 @@ bool SDL_ConvertEventToRenderCoordinates(SDL_Renderer *renderer, SDL_Event *even
return false;
}
SDL_RenderCoordinatesFromWindow(renderer, event->tfinger.x * w, event->tfinger.y * h, &event->tfinger.x, &event->tfinger.y);
+ SDL_RenderVectorFromWindow(renderer, event->tfinger.dx * w, event->tfinger.dy * h, &event->tfinger.dx, &event->tfinger.dy);
}
} else if (event->type == SDL_EVENT_PEN_MOTION) {
SDL_Window *window = SDL_GetWindowFromID(event->pmotion.windowID);