rhi: Remove QVectors from the data description structs as well

As usual, keep some QVector overloads around to allow Qt Quick to compile.

Color attachments and vertex input bindings get an at(index) type of
accessor, unlike any other of similar lists. This is because there the
index is significant, and sequential iteration is not the only type of
operation that is performed. Sometimes a lookup based on an index will
be needed as well.

Task-number: QTBUG-78883
Change-Id: I3882941f09e94ee2f179e0e9b8161551f0d5dae7
Reviewed-by: Christian Strømme <christian.stromme@qt.io>
Reviewed-by: Paul Olav Tvete <paul.tvete@qt.io>

1 files changed, 47 insertions, 41 deletions

diff --git a/src/gui/rhi/qrhimetal.mm b/src/gui/rhi/qrhimetal.mm
index 4dc12f0691..344be44d48 100644
--- a/src/gui/rhi/qrhimetal.mm
+++ b/src/gui/rhi/qrhimetal.mm
@@ -1775,14 +1775,15 @@ void QRhiMetal::beginPass(QRhiCommandBuffer *cb,
             cbD->d->currentPassRpDesc.depthAttachment.loadAction = MTLLoadActionLoad;
             cbD->d->currentPassRpDesc.stencilAttachment.loadAction = MTLLoadActionLoad;
         }
-        const QVector<QRhiColorAttachment> colorAttachments = rtTex->m_desc.colorAttachments();
-        for (const QRhiColorAttachment &colorAttachment : colorAttachments) {
-            if (colorAttachment.texture())
-                QRHI_RES(QMetalTexture, colorAttachment.texture())->lastActiveFrameSlot = currentFrameSlot;
-            else if (colorAttachment.renderBuffer())
-                QRHI_RES(QMetalRenderBuffer, colorAttachment.renderBuffer())->lastActiveFrameSlot = currentFrameSlot;
-            if (colorAttachment.resolveTexture())
-                QRHI_RES(QMetalTexture, colorAttachment.resolveTexture())->lastActiveFrameSlot = currentFrameSlot;
+        for (auto it = rtTex->m_desc.cbeginColorAttachments(), itEnd = rtTex->m_desc.cendColorAttachments();
+             it != itEnd; ++it)
+        {
+            if (it->texture())
+                QRHI_RES(QMetalTexture, it->texture())->lastActiveFrameSlot = currentFrameSlot;
+            else if (it->renderBuffer())
+                QRHI_RES(QMetalRenderBuffer, it->renderBuffer())->lastActiveFrameSlot = currentFrameSlot;
+            if (it->resolveTexture())
+                QRHI_RES(QMetalTexture, it->resolveTexture())->lastActiveFrameSlot = currentFrameSlot;
         }
         if (rtTex->m_desc.depthStencilBuffer())
             QRHI_RES(QMetalRenderBuffer, rtTex->m_desc.depthStencilBuffer())->lastActiveFrameSlot = currentFrameSlot;
@@ -2647,14 +2648,15 @@ void QMetalTextureRenderTarget::release()
 
 QRhiRenderPassDescriptor *QMetalTextureRenderTarget::newCompatibleRenderPassDescriptor()
 {
-    const QVector<QRhiColorAttachment> colorAttachments = m_desc.colorAttachments();
+    const int colorAttachmentCount = m_desc.cendColorAttachments() - m_desc.cbeginColorAttachments();
     QMetalRenderPassDescriptor *rpD = new QMetalRenderPassDescriptor(m_rhi);
-    rpD->colorAttachmentCount = colorAttachments.count();
+    rpD->colorAttachmentCount = colorAttachmentCount;
     rpD->hasDepthStencil = m_desc.depthStencilBuffer() || m_desc.depthTexture();
 
-    for (int i = 0, ie = colorAttachments.count(); i != ie; ++i) {
-        QMetalTexture *texD = QRHI_RES(QMetalTexture, colorAttachments[i].texture());
-        QMetalRenderBuffer *rbD = QRHI_RES(QMetalRenderBuffer, colorAttachments[i].renderBuffer());
+    for (int i = 0; i < colorAttachmentCount; ++i) {
+        const QRhiColorAttachment *colorAtt = m_desc.colorAttachmentAt(i);
+        QMetalTexture *texD = QRHI_RES(QMetalTexture, colorAtt->texture());
+        QMetalRenderBuffer *rbD = QRHI_RES(QMetalRenderBuffer, colorAtt->renderBuffer());
         rpD->colorFormat[i] = int(texD ? texD->d->format : rbD->d->format);
     }
 
@@ -2668,39 +2670,41 @@ QRhiRenderPassDescriptor *QMetalTextureRenderTarget::newCompatibleRenderPassDesc
 
 bool QMetalTextureRenderTarget::build()
 {
-    const QVector<QRhiColorAttachment> colorAttachments = m_desc.colorAttachments();
-    Q_ASSERT(!colorAttachments.isEmpty() || m_desc.depthTexture());
+    const bool hasColorAttachments = m_desc.cbeginColorAttachments() != m_desc.cendColorAttachments();
+    Q_ASSERT(hasColorAttachments || m_desc.depthTexture());
     Q_ASSERT(!m_desc.depthStencilBuffer() || !m_desc.depthTexture());
     const bool hasDepthStencil = m_desc.depthStencilBuffer() || m_desc.depthTexture();
 
-    d->colorAttCount = colorAttachments.count();
-    for (int i = 0; i < d->colorAttCount; ++i) {
-        QMetalTexture *texD = QRHI_RES(QMetalTexture, colorAttachments[i].texture());
-        QMetalRenderBuffer *rbD = QRHI_RES(QMetalRenderBuffer, colorAttachments[i].renderBuffer());
+    d->colorAttCount = 0;
+    int attIndex = 0;
+    for (auto it = m_desc.cbeginColorAttachments(), itEnd = m_desc.cendColorAttachments(); it != itEnd; ++it, ++attIndex) {
+        d->colorAttCount += 1;
+        QMetalTexture *texD = QRHI_RES(QMetalTexture, it->texture());
+        QMetalRenderBuffer *rbD = QRHI_RES(QMetalRenderBuffer, it->renderBuffer());
         Q_ASSERT(texD || rbD);
         id<MTLTexture> dst = nil;
         if (texD) {
             dst = texD->d->tex;
-            if (i == 0) {
+            if (attIndex == 0) {
                 d->pixelSize = texD->pixelSize();
                 d->sampleCount = texD->samples;
             }
         } else if (rbD) {
             dst = rbD->d->tex;
-            if (i == 0) {
+            if (attIndex == 0) {
                 d->pixelSize = rbD->pixelSize();
                 d->sampleCount = rbD->samples;
             }
         }
         QMetalRenderTargetData::ColorAtt colorAtt;
         colorAtt.tex = dst;
-        colorAtt.layer = colorAttachments[i].layer();
-        colorAtt.level = colorAttachments[i].level();
-        QMetalTexture *resTexD = QRHI_RES(QMetalTexture, colorAttachments[i].resolveTexture());
+        colorAtt.layer = it->layer();
+        colorAtt.level = it->level();
+        QMetalTexture *resTexD = QRHI_RES(QMetalTexture, it->resolveTexture());
         colorAtt.resolveTex = resTexD ? resTexD->d->tex : nil;
-        colorAtt.resolveLayer = colorAttachments[i].resolveLayer();
-        colorAtt.resolveLevel = colorAttachments[i].resolveLevel();
-        d->fb.colorAtt[i] = colorAtt;
+        colorAtt.resolveLayer = it->resolveLayer();
+        colorAtt.resolveLevel = it->resolveLevel();
+        d->fb.colorAtt[attIndex] = colorAtt;
     }
     d->dpr = 1;
 
@@ -3119,22 +3123,24 @@ bool QMetalGraphicsPipeline::build()
     const int firstVertexBinding = QRHI_RES(QMetalShaderResourceBindings, m_shaderResourceBindings)->maxBinding + 1;
 
     MTLVertexDescriptor *inputLayout = [MTLVertexDescriptor vertexDescriptor];
-    const QVector<QRhiVertexInputAttribute> attributes = m_vertexInputLayout.attributes();
-    for (const QRhiVertexInputAttribute &attribute : attributes) {
-        const uint loc = uint(attribute.location());
-        inputLayout.attributes[loc].format = toMetalAttributeFormat(attribute.format());
-        inputLayout.attributes[loc].offset = NSUInteger(attribute.offset());
-        inputLayout.attributes[loc].bufferIndex = NSUInteger(firstVertexBinding + attribute.binding());
-    }
-    const QVector<QRhiVertexInputBinding> bindings = m_vertexInputLayout.bindings();
-    for (int i = 0, ie = bindings.count(); i != ie; ++i) {
-        const QRhiVertexInputBinding &binding(bindings[i]);
-        const uint layoutIdx = uint(firstVertexBinding + i);
+    for (auto it = m_vertexInputLayout.cbeginAttributes(), itEnd = m_vertexInputLayout.cendAttributes();
+         it != itEnd; ++it)
+    {
+        const uint loc = uint(it->location());
+        inputLayout.attributes[loc].format = toMetalAttributeFormat(it->format());
+        inputLayout.attributes[loc].offset = NSUInteger(it->offset());
+        inputLayout.attributes[loc].bufferIndex = NSUInteger(firstVertexBinding + it->binding());
+    }
+    int bindingIndex = 0;
+    for (auto it = m_vertexInputLayout.cbeginBindings(), itEnd = m_vertexInputLayout.cendBindings();
+         it != itEnd; ++it, ++bindingIndex)
+    {
+        const uint layoutIdx = uint(firstVertexBinding + bindingIndex);
         inputLayout.layouts[layoutIdx].stepFunction =
-                binding.classification() == QRhiVertexInputBinding::PerInstance
+                it->classification() == QRhiVertexInputBinding::PerInstance
                 ? MTLVertexStepFunctionPerInstance : MTLVertexStepFunctionPerVertex;
-        inputLayout.layouts[layoutIdx].stepRate = NSUInteger(binding.instanceStepRate());
-        inputLayout.layouts[layoutIdx].stride = binding.stride();
+        inputLayout.layouts[layoutIdx].stepRate = NSUInteger(it->instanceStepRate());
+        inputLayout.layouts[layoutIdx].stride = it->stride();
     }
 
     MTLRenderPipelineDescriptor *rpDesc = [[MTLRenderPipelineDescriptor alloc] init];