[Draft] Rework text vertex calculation

samples/06_Widgets/Widgets.cpp

@@ -33,17 +33,20 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 #include "UI/UiService.h"
 #include "UI/Button.h"
 #include "UI/Panel.h"
+#include "UI/Text.h"
 
 using namespace OSRE;
 using namespace OSRE::App;
 using namespace OSRE::RenderBackend;
 using namespace OSRE::Common;
 
 static Ui::WidgetBase *createUi() {
-    Rect2i r1(10, 10, 200, 100);
+    Rect2i r1(100, 100, 400, 400);
     Ui::Panel *panel = Ui::UiService::getInstance()->createPanel("root", r1, nullptr);
-    Rect2i r2(20, 20, 160, 40);
-    panel->addWidget(new Ui::Button("Quit", r2, panel));
+    Rect2i r2(120, 120, 160, 40);
+
+    Ui::Text *text = new Ui::Text("Hello World", r2, panel);
+    panel->addWidget(text);
     return panel;
 }
 
@@ -61,6 +64,7 @@ class WidgetsApp final : public AppBase {
 
     /// @brief
     WidgetsApp(int argc, char *argv[]) : AppBase(argc, const_cast<const char **>(argv)) {
+        // empty
     }
 
     /// The class destructor.

src/Engine/CMakeLists.txt

@@ -374,6 +374,8 @@ SET(ui_src
     UI/Panel.h
     UI/UiService.cpp
     UI/UiService.h
+    UI/Text.cpp
+    UI/Text.h
     UI/TextPanel.cpp
     UI/TextPanel.h
     UI/WidgetBase.h

src/Engine/RenderBackend/2D/CanvasRenderer.cpp

@@ -37,13 +37,86 @@
 
 DECL_OSRE_LOG_MODULE(CanvasRenderer)
 
+static constexpr size_t NumQuadVert = 4;
+static constexpr ui32 NumQuadIndices = 6;
+
 // will rescale coordinates from absolute coordinates into model space coordinates
 inline void mapCoordinates(const Rect2i &resolution, i32 x, i32 y, f32 &xOut, f32 &yOut) {
-    xOut = (2.0f * static_cast<f32>(x)  / static_cast<f32>(resolution.width)) - 1.0f;
+    xOut = (2.0f * static_cast<f32>(x) / static_cast<f32>(resolution.width)) - 1.0f;
     yOut = (2.0f * static_cast<f32>(y) / static_cast<f32>(resolution.height)) - 1.0f;
     yOut = -1.0f * yOut;
 }
 
+static void generateTextBoxVerticesAndIndices(const Rect2i &resolution, i32 x, i32 y, i32 textSize, i32 layer, const String &text,
+        Vec3Array &positions, Vec3Array &colors, Vec2Array &tex0, cppcore::TArray<ui16> &textIndices) {
+    using namespace ::OSRE::Common;
+
+    const size_t NumTextVerts = MeshUtilities::getNumTextVerts(text);
+    positions.resize(NumTextVerts);
+    colors.resize(NumTextVerts);
+    tex0.resize(NumTextVerts);
+    textIndices.resize(MeshUtilities::getNumTextIndices(text));
+
+    const f32 invCol = 1.f / 16.f;
+    const f32 invRow = 1.f / 16.f;
+    ui32 textCol(0), textRow(0);
+    for (size_t i = 0; i < text.size(); i++) {
+        const i32 colOffset = textCol * textSize;
+        const c8 ch = text[i];
+        if (Tokenizer::isLineBreak(ch)) {
+            textCol = 0;
+            ++textRow;
+            continue;
+        }
+
+        const ui16 VertexOffset = static_cast<ui16>(i) * static_cast<ui16>(NumQuadVert);
+        const i32 rowHeight = -1 * textRow * textSize;
+
+        mapCoordinates(resolution, x + colOffset, y + rowHeight, positions[VertexOffset + 0].x, positions[VertexOffset + 0].y);
+        positions[VertexOffset + 0].z = static_cast<f32>(-layer);
+
+        mapCoordinates(resolution, x + colOffset, y + textSize + rowHeight, positions[VertexOffset + 1].x, positions[VertexOffset + 1].y);
+        positions[VertexOffset + 1].z = static_cast<f32>(-layer);
+
+        mapCoordinates(resolution, x + textSize + colOffset, y + rowHeight, positions[VertexOffset + 2].x, positions[VertexOffset + 2].y);
+        positions[VertexOffset + 2].z = static_cast<f32>(-layer);
+
+        mapCoordinates(resolution, x + textSize + colOffset, y + textSize + rowHeight, positions[VertexOffset + 3].x, positions[VertexOffset + 3].y);
+        positions[VertexOffset + 3].z = static_cast<f32>(-layer);
+
+        const i32 column = (ch) % 16;
+        const i32 row = (ch) / 16;
+        const f32 s = column * invCol;
+        const f32 t = (row + 1) * invRow;
+
+        tex0[VertexOffset + 0].x = s;
+        tex0[VertexOffset + 0].y = 1.0f - t;
+
+        tex0[VertexOffset + 1].x = s;
+        tex0[VertexOffset + 1].y = 1.0f - t + 1.0f / 16.0f;
+
+        tex0[VertexOffset + 2].x = s + 1.0f / 16.0f;
+        tex0[VertexOffset + 2].y = 1.0f - t;
+
+        tex0[VertexOffset + 3].x = s + 1.0f / 16.0f;
+        tex0[VertexOffset + 3].y = 1.0f - t + 1.0f / 16.0f;
+
+        colors[VertexOffset + 0] = glm::vec3(0, 0, 0);
+        colors[VertexOffset + 1] = glm::vec3(0, 0, 0);
+        colors[VertexOffset + 2] = glm::vec3(0, 0, 0);
+        colors[VertexOffset + 3] = glm::vec3(0, 0, 0);
+        const ui32 IndexOffset = i * NumQuadIndices;
+        textIndices[0 + IndexOffset] = 0 + VertexOffset;
+        textIndices[1 + IndexOffset] = 2 + VertexOffset;
+        textIndices[2 + IndexOffset] = 1 + VertexOffset;
+
+        textIndices[3 + IndexOffset] = 1 + VertexOffset;
+        textIndices[4 + IndexOffset] = 2 + VertexOffset;
+        textIndices[5 + IndexOffset] = 3 + VertexOffset;
+        ++textCol;
+    }
+}
+
 inline void clip(const Rect2i &resolution, i32 x, i32 y, i32 &x_out, i32 &y_out) {
     x_out = x;
     y_out = y;
@@ -146,13 +219,7 @@
 }
 
 CanvasRenderer::CanvasRenderer(i32 numLayers, i32 x, i32 y, i32 w, i32 h) :
-        mDirty(true),
-        mPenColor(1, 1, 1, 0),
-        mActiveLayer(0),
-        mNumLayers(numLayers),
-        mFont(nullptr),
-        mMesh(nullptr),
-        mText(nullptr) {
+        mDirty(true), mPenColor(1, 1, 1, 0), mActiveLayer(0), mNumLayers(numLayers) {
     setResolution(x, y, w, h);
 }
 
@@ -165,6 +232,7 @@
 
 void CanvasRenderer::preRender(RenderBackendService *rbSrv) {
     if (rbSrv == nullptr) {
+        osre_error(Tag, "Render-Backend is nullptr.");
         return;
     }
 
@@ -176,6 +244,7 @@
 
 void CanvasRenderer::render(RenderBackendService *rbSrv) {
     if (rbSrv == nullptr) {
+        osre_error(Tag, "Render-Backend is nullptr.");
         return;
     }
 
@@ -432,15 +501,15 @@
         usedSize = mFont->Size;
     }
 
-    f32 x_model = 0.0f;
-    f32 y_model = 0.0f;
-    mapCoordinates(mResolution, x, y, x_model, y_model);
     Vec3Array positions;
     Vec3Array colors;
     Vec2Array tex0;
     TArray<ui16> indices;
-    const f32 fontSize = static_cast<f32>(usedSize) / static_cast<f32>(mResolution.getWidth());
-    MeshUtilities::generateTextBoxVerticesAndIndices(x_model, y_model, fontSize, text, positions, colors, tex0, indices);
+    f32 xModel{ 0.f }, yModel{ 0.f };
+    mapCoordinates(mResolution, x, y, xModel, yModel);
+
+    //MeshUtilities::generateTextBoxVerticesAndIndices(xModel, yModel, usedSize, text, positions, colors, tex0, indices);
+    generateTextBoxVerticesAndIndices(mResolution, x, y, usedSize, mActiveLayer-2, text, positions, colors, tex0, indices);
 
     DrawCmd *drawCmd = alloc();
     drawCmd->PrimType = PrimitiveType::TriangleList;
@@ -455,7 +524,7 @@
         drawCmd->Vertices[posIndex].color0 = mPenColor.toVec3();
         drawCmd->Vertices[posIndex].position.x = positions[posIndex].x;
         drawCmd->Vertices[posIndex].position.y = positions[posIndex].y;
-        drawCmd->Vertices[posIndex].position.z = static_cast<f32>(-mActiveLayer);
+        drawCmd->Vertices[posIndex].position.z = positions[posIndex].z;
         drawCmd->Vertices[posIndex].tex0.x = tex0[posIndex].x;
         drawCmd->Vertices[posIndex].tex0.y = tex0[posIndex].y;
     }

src/Engine/RenderBackend/2D/CanvasRenderer.h

@@ -163,9 +163,9 @@ class OSRE_EXPORT CanvasRenderer : public IRenderPath {
     Rect2i mResolution;
     i32 mActiveLayer;
     i32 mNumLayers;
-    Font *mFont;
-    Mesh *mMesh;
-    Mesh *mText;
+    Font *mFont = nullptr;
+    Mesh *mMesh = nullptr;
+    Mesh *mText = nullptr;
 };
 
 inline Font* CanvasRenderer::getActiveFont() const {

src/Engine/UI/Button.cpp

@@ -28,12 +28,15 @@ namespace OSRE::Ui {
 using namespace ::OSRE::RenderBackend;
 
 Button::Button(const String &label, const Rect2i &rect, WidgetBase *parent) : 
-		WidgetBase(rect, parent), mLabel(label) {
+		WidgetBase(rect, parent), mText(nullptr) {
     setDirty();
+    if (!label.empty()) {
+        setLabel(label);
+    }
 }
 
 Button::~Button() {
-    // empty
+    delete mText;
 }
 
 void Button::onUpdate() {
@@ -48,9 +51,6 @@ void Button::onRender(CanvasRenderer *renderer) {
         renderer->setColor(Color4(0.5f, 0.5f, 0.5f, 1.0f));
         const Rect2i &r = getRect();
         renderer->drawRect(r.x1, r.y1, r.width, r.height, true);
-        if (!mLabel.empty()) {
-            renderer->drawText(r.x1+1, r.y1+1, 40, mLabel);
-        }
         setClean();
     }
 }

src/Engine/UI/Button.h

@@ -21,8 +21,9 @@ IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 -----------------------------------------------------------------------------------------------*/
 #include "WidgetBase.h"
+#include "UI/Text.h"
 
-namespace OSRE::Ui {
+ namespace OSRE::Ui {
 
 //-------------------------------------------------------------------------------------------------
 ///	@ingroup	Engine
@@ -41,20 +42,24 @@ class OSRE_EXPORT Button : public WidgetBase {
     void onRender(RenderBackend::CanvasRenderer *renderer) override;
 
 private:
-    String mLabel;
+    Text *mText;
 };
 
 inline void Button::setLabel(const String &text) {
-    if (text == mLabel) {
+    if (mText == nullptr) {
+        mText = new Text(text, getRect(), this);
         return;
     }
-
-    mLabel = text;
-    setDirty();
+
+    mText->setLabel(text);
 }
 
 inline const String &Button::getLabel() const {
-    return mLabel;
+    if (mText == nullptr) {
+        return String();
+    }
+
+    return mText->getLabel();
 }
 
 } // namespace OSRE::Ui

src/Engine/UI/Text.cpp

@@ -0,0 +1,64 @@
+/*-----------------------------------------------------------------------------------------------
+The MIT License (MIT)
+
+Copyright (c) 2015-2025 OSRE ( Open Source Render Engine ) by Kim Kulling
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+the Software, and to permit persons to whom the Software is furnished to do so,
+subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+-----------------------------------------------------------------------------------------------*/
+#include "UI/Text.h"
+
+namespace OSRE::Ui {
+
+Text::Text(const String &label, const Rect2i &rect, WidgetBase *parent) :
+        WidgetBase(rect, parent), mLabel(label) {
+    setDirty();
+}
+
+Text::~Text() {
+    // empty
+}
+
+void Text::setLabel(const String &text) {
+    if (text == mLabel) {
+        return;
+    }
+    mLabel = text;
+    setDirty();
+}
+
+const String &Text::getLabel() const {
+    return mLabel;
+}
+
+void Text::onUpdate() {
+    // empty
+}
+
+void Text::onRender(RenderBackend::CanvasRenderer *renderer) {
+    osre_assert(renderer != nullptr);
+
+    if (isDirty()) {
+        renderer->selectLayer(1);
+        renderer->setColor(Color4(0.5f, 0.5f, 0.5f, 1.0f));
+        const Rect2i &r = getRect();
+        renderer->drawText(r.x1 + 1, r.y1 + 1, 40, mLabel);
+        setClean();
+    }
+}
+
+} // namespace OSRE::Ui

src/Engine/UI/Text.h

@@ -0,0 +1,50 @@
+/*-----------------------------------------------------------------------------------------------
+The MIT License (MIT)
+
+Copyright (c) 2015-2025 OSRE ( Open Source Render Engine ) by Kim Kulling
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+the Software, and to permit persons to whom the Software is furnished to do so,
+subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+-----------------------------------------------------------------------------------------------*/
+#pragma once
+
+#include "UI/WidgetBase.h"
+#include "RenderBackend/2D/CanvasRenderer.h"
+
+namespace OSRE::Ui {
+
+//-------------------------------------------------------------------------------------------------
+///	@ingroup	Engine
+///
+///	@brief Todo!
+//-------------------------------------------------------------------------------------------------
+class OSRE_EXPORT Text : public WidgetBase {
+public:
+    Text(const String &label, const Rect2i &rect, WidgetBase *parent = nullptr);
+    ~Text() override;
+    void setLabel(const String &text);
+    const String &getLabel() const;
+
+protected:
+    void onUpdate() override;
+    void onRender(RenderBackend::CanvasRenderer *renderer) override;
+
+private:
+    String mLabel;
+};
+
+} // namespace OSRE::Ui