diff --git a/src/video_core/engines/maxwell_3d.cpp b/src/video_core/engines/maxwell_3d.cpp
index a46ed4bd7e8ddc0f531a8c672dbfba636e2b3b11..68f91cc7569617e1980095b81a1fcb47c807b561 100644
--- a/src/video_core/engines/maxwell_3d.cpp
+++ b/src/video_core/engines/maxwell_3d.cpp
@@ -222,6 +222,18 @@ void Maxwell3D::DrawArrays() {
debug_context->OnEvent(Tegra::DebugContext::Event::FinishedPrimitiveBatch, nullptr);
}
+ // Both instance configuration registers can not be set at the same time.
+ ASSERT_MSG(!regs.draw.instance_next || !regs.draw.instance_cont,
+ "Illegal combination of instancing parameters");
+
+ if (regs.draw.instance_next) {
+ // Increment the current instance *before* drawing.
+ state.current_instance += 1;
+ } else if (!regs.draw.instance_cont) {
+ // Reset the current instance to 0.
+ state.current_instance = 0;
+ }
+
const bool is_indexed{regs.index_array.count && !regs.vertex_buffer.count};
rasterizer.AccelerateDrawBatch(is_indexed);
diff --git a/src/video_core/engines/maxwell_3d.h b/src/video_core/engines/maxwell_3d.h
index 1b30ce01853c3e77fb56feca183a49ba08fc69d9..771eb5abcb5f448db5af03c98740154272d11dd0 100644
--- a/src/video_core/engines/maxwell_3d.h
+++ b/src/video_core/engines/maxwell_3d.h
@@ -638,6 +638,8 @@ public:
union {
u32 vertex_begin_gl;
BitField<0, 16, PrimitiveTopology> topology;
+ BitField<26, 1, u32> instance_next;
+ BitField<27, 1, u32> instance_cont;
};
} draw;
@@ -830,6 +832,7 @@ public:
};
std::array<ShaderStageInfo, Regs::MaxShaderStage> shader_stages;
+ u32 current_instance = 0; ///< Current instance to be used to simulate instanced rendering.
};
State state{};
diff --git a/src/video_core/renderer_opengl/gl_rasterizer.cpp b/src/video_core/renderer_opengl/gl_rasterizer.cpp
index 9d1549fe9e7227ee1e720d87d503a5af1ed3f47a..93eadde7a7b7f720cced4eafab073e2f6d2a7a14 100644
--- a/src/video_core/renderer_opengl/gl_rasterizer.cpp
+++ b/src/video_core/renderer_opengl/gl_rasterizer.cpp
@@ -124,7 +124,7 @@ std::pair<u8*, GLintptr> RasterizerOpenGL::SetupVertexArrays(u8* array_ptr,
glBindVertexBuffer(index, stream_buffer.GetHandle(), vertex_buffer_offset,
vertex_array.stride);
- ASSERT_MSG(vertex_array.divisor == 0, "Vertex buffer divisor unimplemented");
+ ASSERT_MSG(vertex_array.divisor == 0, "Instanced vertex arrays are not supported");
}
// Use the vertex array as-is, assumes that the data is formatted correctly for OpenGL.
diff --git a/src/video_core/renderer_opengl/gl_shader_decompiler.cpp b/src/video_core/renderer_opengl/gl_shader_decompiler.cpp
index dabf98b742fdc942998816d93070d6be7eb771b6..5a05c79ef2059feaba30c79c342187f2fa32489f 100644
--- a/src/video_core/renderer_opengl/gl_shader_decompiler.cpp
+++ b/src/video_core/renderer_opengl/gl_shader_decompiler.cpp
@@ -538,7 +538,7 @@ private:
// vertex shader, and what's the value of the fourth element when inside a Tess Eval
// shader.
ASSERT(stage == Maxwell3D::Regs::ShaderStage::Vertex);
- return "vec4(0, 0, uintBitsToFloat(gl_InstanceID), uintBitsToFloat(gl_VertexID))";
+ return "vec4(0, 0, uintBitsToFloat(instance_id.x), uintBitsToFloat(gl_VertexID))";
default:
const u32 index{static_cast<u32>(attribute) -
static_cast<u32>(Attribute::Index::Attribute_0)};
diff --git a/src/video_core/renderer_opengl/gl_shader_gen.cpp b/src/video_core/renderer_opengl/gl_shader_gen.cpp
index 129c777d18b383a8679fc266b7769daebdd74467..57e0e17261957fa7888d0ea6dd0ab5ad8c848e9c 100644
--- a/src/video_core/renderer_opengl/gl_shader_gen.cpp
+++ b/src/video_core/renderer_opengl/gl_shader_gen.cpp
@@ -38,6 +38,7 @@ out vec4 position;
layout (std140) uniform vs_config {
vec4 viewport_flip;
+ uvec4 instance_id;
};
void main() {
@@ -90,6 +91,7 @@ out vec4 color;
layout (std140) uniform fs_config {
vec4 viewport_flip;
+ uvec4 instance_id;
};
void main() {
diff --git a/src/video_core/renderer_opengl/gl_shader_manager.cpp b/src/video_core/renderer_opengl/gl_shader_manager.cpp
index 415d42fdacc7675b45b07088cd8b9ed7641ef9e4..f0886caac0c04217a31ee8b292dd0d10f2f72734 100644
--- a/src/video_core/renderer_opengl/gl_shader_manager.cpp
+++ b/src/video_core/renderer_opengl/gl_shader_manager.cpp
@@ -37,11 +37,16 @@ void SetShaderUniformBlockBindings(GLuint shader) {
} // namespace Impl
void MaxwellUniformData::SetFromRegs(const Maxwell3D::State::ShaderStageInfo& shader_stage) {
- const auto& regs = Core::System::GetInstance().GPU().Maxwell3D().regs;
+ const auto& gpu = Core::System::GetInstance().GPU().Maxwell3D();
+ const auto& regs = gpu.regs;
+ const auto& state = gpu.state;
// TODO(bunnei): Support more than one viewport
viewport_flip[0] = regs.viewport_transform[0].scale_x < 0.0 ? -1.0f : 1.0f;
viewport_flip[1] = regs.viewport_transform[0].scale_y < 0.0 ? -1.0f : 1.0f;
+
+ // We only assign the instance to the first component of the vector, the rest is just padding.
+ instance_id[0] = state.current_instance;
}
} // namespace GLShader
diff --git a/src/video_core/renderer_opengl/gl_shader_manager.h b/src/video_core/renderer_opengl/gl_shader_manager.h
index 716933a0b54a1b016122ebb0e10b4b320bbd25ee..75fa7360553e85410b9822c4092d9579b2a1bc3f 100644
--- a/src/video_core/renderer_opengl/gl_shader_manager.h
+++ b/src/video_core/renderer_opengl/gl_shader_manager.h
@@ -24,14 +24,15 @@ void SetShaderUniformBlockBindings(GLuint shader);
} // namespace Impl
/// Uniform structure for the Uniform Buffer Object, all vectors must be 16-byte aligned
-// NOTE: Always keep a vec4 at the end. The GL spec is not clear wether the alignment at
+// NOTE: Always keep a vec4 at the end. The GL spec is not clear whether the alignment at
// the end of a uniform block is included in UNIFORM_BLOCK_DATA_SIZE or not.
// Not following that rule will cause problems on some AMD drivers.
struct MaxwellUniformData {
void SetFromRegs(const Maxwell3D::State::ShaderStageInfo& shader_stage);
alignas(16) GLvec4 viewport_flip;
+ alignas(16) GLuvec4 instance_id;
};
-static_assert(sizeof(MaxwellUniformData) == 16, "MaxwellUniformData structure size is incorrect");
+static_assert(sizeof(MaxwellUniformData) == 32, "MaxwellUniformData structure size is incorrect");
static_assert(sizeof(MaxwellUniformData) < 16384,
"MaxwellUniformData structure must be less than 16kb as per the OpenGL spec");