Line drawing code now supports all zoom levels.

data/shaders/drawline.vert

@@ -7,7 +7,6 @@ uniform ivec2 uScreenSize;
 
 // clang-format off
 in ivec4 vBounds;
-in ivec4 vClip;
 in uint  vColour;
 in int   vDepth;
 // clang-format on
@@ -18,7 +17,7 @@ flat out uint fColour;
 
 void main()
 {
-    vec2 pos = clamp(vVertMat * vec4(vBounds), vec2(vClip.xy), vec2(vClip.zw));
+    vec2 pos = vVertMat * vec4(vBounds);
 
     // Transform screen coordinates to viewport coordinates
     pos = (pos * (2.0 / vec2(uScreenSize))) - 1.0;

src/openrct2-ui/drawing/engines/opengl/DrawCommands.h

@@ -93,7 +93,6 @@ namespace OpenRCT2::Ui
 
     struct DrawLineCommand
     {
-        ivec4 clip;
         ivec4 bounds;
         GLuint colour;
         GLint depth;

src/openrct2-ui/drawing/engines/opengl/DrawLineShader.cpp

@@ -51,7 +51,6 @@ DrawLineShader::DrawLineShader()
         vVertMat + 3, 2, GL_FLOAT, GL_FALSE, sizeof(VDStruct), reinterpret_cast<void*>(offsetof(VDStruct, mat[3])));
 
     glBindBuffer(GL_ARRAY_BUFFER, _vboInstances);
-    glVertexAttribIPointer(vClip, 4, GL_INT, sizeof(DrawLineCommand), reinterpret_cast<void*>(offsetof(DrawLineCommand, clip)));
     glVertexAttribIPointer(
         vBounds, 4, GL_INT, sizeof(DrawLineCommand), reinterpret_cast<void*>(offsetof(DrawLineCommand, bounds)));
     glVertexAttribIPointer(
@@ -69,7 +68,6 @@ DrawLineShader::DrawLineShader()
     glEnableVertexAttribArray(vColour);
     glEnableVertexAttribArray(vDepth);
 
-    glVertexAttribDivisor(vClip, 1);
     glVertexAttribDivisor(vBounds, 1);
     glVertexAttribDivisor(vColour, 1);
     glVertexAttribDivisor(vDepth, 1);
@@ -87,7 +85,6 @@ void DrawLineShader::GetLocations()
 {
     uScreenSize = GetUniformLocation("uScreenSize");
 
-    vClip = GetAttributeLocation("vClip");
     vBounds = GetAttributeLocation("vBounds");
     vColour = GetAttributeLocation("vColour");
     vDepth = GetAttributeLocation("vDepth");

src/openrct2-ui/drawing/engines/opengl/OpenGLDrawingEngine.cpp

@@ -578,12 +578,17 @@ void OpenGLDrawingContext::FilterRect(
 
 void OpenGLDrawingContext::DrawLine(DrawPixelInfo& dpi, uint32_t colour, const ScreenLine& line)
 {
+    // Note: this function does not respect DPI bounds.
     CalculcateClipping(dpi);
 
     DrawLineCommand& command = _commandBuffers.lines.allocate();
 
-    command.clip = { _clipLeft, _clipTop, _clipRight, _clipBottom };
-    command.bounds = { line.GetX1() + _offsetX, line.GetY1() + _offsetY, line.GetX2() + _offsetX, line.GetY2() + _offsetY };
+    const int32_t x1 = dpi.zoom_level.ApplyInversedTo(line.GetX1() - dpi.x) + _clipLeft;
+    const int32_t y1 = dpi.zoom_level.ApplyInversedTo(line.GetY1() - dpi.y) + _clipTop;
+    const int32_t x2 = dpi.zoom_level.ApplyInversedTo(line.GetX2() - dpi.x) + _clipLeft;
+    const int32_t y2 = dpi.zoom_level.ApplyInversedTo(line.GetY2() - dpi.y) + _clipTop;
+
+    command.bounds = { x1, y1, x2, y2 };
     command.colour = colour & 0xFF;
     command.depth = _drawCount++;
 }

src/openrct2/drawing/Line.cpp

@@ -20,10 +20,16 @@ static void GfxDrawLineOnBuffer(DrawPixelInfo& dpi, char colour, const ScreenCoo
 {
     ScreenCoordsXY offset{ coords.x - dpi.x, coords.y - dpi.y };
 
+    offset.x = dpi.zoom_level.ApplyInversedTo(offset.x);
+    offset.y = dpi.zoom_level.ApplyInversedTo(offset.y);
+    no_pixels = dpi.zoom_level.ApplyInversedTo(no_pixels);
+    const int32_t width = dpi.zoom_level.ApplyInversedTo(dpi.width);
+    const int32_t height = dpi.zoom_level.ApplyInversedTo(dpi.height);
+
     // Check to make sure point is in the y range
     if (offset.y < 0)
         return;
-    if (offset.y >= dpi.height)
+    if (offset.y >= height)
         return;
     // Check to make sure we are drawing at least a pixel
     if (!no_pixels)
@@ -41,18 +47,17 @@ static void GfxDrawLineOnBuffer(DrawPixelInfo& dpi, char colour, const ScreenCoo
     }
 
     // Ensure that the end point of the line is within range
-    if (offset.x + no_pixels - dpi.width > 0)
+    if (offset.x + no_pixels - width > 0)
     {
         // If the end point has any pixels outside range
         // cut them off. If there are now no pixels return.
-        no_pixels -= offset.x + no_pixels - dpi.width;
+        no_pixels -= offset.x + no_pixels - width;
         if (no_pixels <= 0)
             return;
     }
 
     // Get the buffer we are drawing to and move to the first coordinate.
-    uint8_t* bits_pointer = dpi.bits
-        + offset.y * (static_cast<int64_t>(static_cast<int64_t>(dpi.pitch) + static_cast<int64_t>(dpi.width))) + offset.x;
+    uint8_t* bits_pointer = dpi.bits + offset.y * (static_cast<int64_t>(dpi.pitch) + static_cast<int64_t>(width)) + offset.x;
 
     // Draw the line to the specified colour
     for (; no_pixels > 0; --no_pixels, ++bits_pointer)

src/openrct2/paint/Paint.cpp

@@ -536,7 +536,7 @@ static void PaintDrawStruct(PaintSession& session, PaintStruct* ps)
     }
 
     auto imageId = PaintPSColourifyImage(ps, ps->image_id, session.ViewFlags);
-    if (gPaintBoundingBoxes && session.DPI.zoom_level == ZoomLevel{ 0 })
+    if (gPaintBoundingBoxes)
     {
         PaintPSImageWithBoundingBoxes(session, ps, imageId, screenPos.x, screenPos.y);
     }