Metal Effect support!

icculus · Jan 12, 2020 · 7985e19 · 7985e19
1 parent 1450aee
commit 7985e19
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diff --git a/CMakeLists.txt b/CMakeLists.txt
@@ -162,6 +162,7 @@ ADD_LIBRARY(mojoshader ${LIBRARY_FORMAT}
     mojoshader.c
     mojoshader_common.c
     mojoshader_opengl.c
+    mojoshader_metal.c
     profiles/mojoshader_profile_arb1.c
     profiles/mojoshader_profile_bytecode.c
     profiles/mojoshader_profile_d3d.c

diff --git a/mojoshader.h b/mojoshader.h
@@ -3252,6 +3252,56 @@ DECLSPEC void MOJOSHADER_glDeleteShader(MOJOSHADER_glShader *shader);
  */
 DECLSPEC void MOJOSHADER_glDestroyContext(MOJOSHADER_glContext *ctx);
 
+
+/* Metal interface... */
+
+typedef struct MOJOSHADER_mtlShader MOJOSHADER_mtlShader;
+
+/*
+ * Get the MTLFunction* from the given MOJOSHADER_mtlShader.
+ *
+ * This function calls [retain] on the MTLFunction* before returning!
+ *  Please call [release] on the result when you no longer need it.
+ */
+DECLSPEC void *MOJOSHADER_mtlGetFunctionHandle(MOJOSHADER_mtlShader *shader);
+
+/*
+ * Swaps uniform buffers and resets offsets to prepare for the next frame.
+ *
+ * Always call this after submitting the final command buffer for a frame!
+ */
+DECLSPEC void MOJOSHADER_mtlEndFrame();
+
+/*
+ * Return the location of a vertex attribute for the given shader.
+ *
+ * (usage) and (index) map to Direct3D vertex declaration values: COLOR1 would
+ *  be MOJOSHADER_USAGE_COLOR and 1.
+ *
+ * The return value is the index of the attribute to be used to create
+ *  a MTLVertexAttributeDescriptor, or -1 if the stream is not used.
+ */
+int MOJOSHADER_mtlGetVertexAttribLocation(MOJOSHADER_mtlShader *vert,
+                                          MOJOSHADER_usage usage, int index);
+
+/*
+ * Get any error state we might have picked up, such as failed shader
+ *  compilation.
+ *
+ * Returns a human-readable string. This string is for debugging purposes, and
+ *  not guaranteed to be localized, coherent, or user-friendly in any way.
+ *  It's for programmers!
+ *
+ * The latest error may remain between calls. New errors replace any existing
+ *  error. Don't check this string for a sign that an error happened, check
+ *  return codes instead and use this for explanation when debugging.
+ *
+ * Do not free the returned string: it's a pointer to a static internal
+ *  buffer. Do not keep the pointer around, either, as it's likely to become
+ *  invalid as soon as you call into MojoShader again.
+ */
+DECLSPEC const char *MOJOSHADER_mtlGetError(void);
+
 #ifdef __cplusplus
 }
 #endif

diff --git a/mojoshader_effects.h b/mojoshader_effects.h
@@ -800,6 +800,119 @@ DECLSPEC void MOJOSHADER_glEffectEndPass(MOJOSHADER_glEffect *glEffect);
  */
 DECLSPEC void MOJOSHADER_glEffectEnd(MOJOSHADER_glEffect *glEffect);
 
+
+/* Metal effect interface... */
+
+typedef struct MOJOSHADER_mtlEffect MOJOSHADER_mtlEffect;
+typedef struct MOJOSHADER_mtlShader MOJOSHADER_mtlShader;
+typedef struct MOJOSHADER_mtlShaderState MOJOSHADER_mtlShaderState;
+
+/* Fully compile/link the shaders found within the effect.
+ *
+ * The MOJOSHADER_mtlEffect* is solely for use within the Metal-specific calls.
+ *  In all other cases you will be using the MOJOSHADER_effect* instead.
+ *
+ * In a typical use case, you will be calling this immediately after obtaining
+ *  the MOJOSHADER_effect*.
+ *
+ * (effect) is a MOJOSHADER_effect* obtained from MOJOSHADER_parseEffect().
+ * (mtlDevice) is a MTLDevice* obtained from a Metal device creation call,
+ *  such as MTLCreateSystemDefaultDevice().
+ * (numBackingBuffers) is the number of backing uniform buffers that you
+ *  want to create for each shader. If you are using double-buffering,
+ *  this should be 2; for triple buffering, this should be 3, etc.
+ *
+ * This function returns a MOJOSHADER_mtlEffect*, containing Metal-specific
+ *  data for an accompanying MOJOSHADER_effect*.
+ */
+DECLSPEC MOJOSHADER_mtlEffect *MOJOSHADER_mtlCompileEffect(MOJOSHADER_effect *effect,
+                                                           void *mtlDevice,
+                                                           int numBackingBuffers);
+
+/* Delete the shaders that were allocated for an effect.
+ *
+ * (mtlEffect) is a MOJOSHADER_mtlEffect* obtained from
+ *  MOJOSHADER_mtlCompileEffect().
+ */
+DECLSPEC void MOJOSHADER_mtlDeleteEffect(MOJOSHADER_mtlEffect *mtlEffect);
+
+/* Prepare the effect for rendering with the currently applied technique.
+ *
+ * This function maps to ID3DXEffect::Begin.
+ *
+ * In addition to the expected Begin parameters, we also include a parameter
+ *  to pass in a MOJOSHADER_effectRenderState. Rather than change the render
+ *  state within MojoShader itself we will simply provide what the effect wants
+ *  and allow you to use this information with your own renderer.
+ *  MOJOSHADER_glEffectBeginPass will update with the render state desired by
+ *  the current effect pass.
+ *
+ * Note that we only provide the ability to preserve the shader state, but NOT
+ * the ability to preserve the render/sampler states. You are expected to
+ * track your own Metal state and restore these states as needed for your
+ * application.
+ *
+ * (mtlEffect) is a MOJOSHADER_mtlEffect* obtained from
+ *  MOJOSHADER_mtlCompileEffect().
+ * (numPasses) will be filled with the number of passes that this technique
+ *  will need to fully render.
+ * (saveShaderState) is a boolean value informing the effect whether or not to
+ *  restore the shader bindings after calling MOJOSHADER_mtlEffectEnd.
+ * (renderState) will be filled by the effect to inform you of the render state
+ *  changes introduced by the technique and its passes.
+ */
+DECLSPEC void MOJOSHADER_mtlEffectBegin(MOJOSHADER_mtlEffect *mtlEffect,
+                                        unsigned int *numPasses,
+                                        int saveShaderState,
+                                        MOJOSHADER_effectStateChanges *stateChanges);
+
+/* Begin an effect pass from the currently applied technique.
+ *
+ * This function maps to ID3DXEffect::BeginPass.
+ *
+ * (mtlEffect) is a MOJOSHADER_mtlEffect* obtained from
+ *  MOJOSHADER_mtlCompileEffect().
+ * (pass) is the index of the effect pass as found in the current technique.
+ * (state) is a pointer to the current shader state object.
+ *
+ * The MOJOSHADER_mtlShaderState pointed to by (shState) must be created
+ * before calling this function!
+ */
+DECLSPEC void MOJOSHADER_mtlEffectBeginPass(MOJOSHADER_mtlEffect *mtlEffect,
+                                            unsigned int pass,
+                                            MOJOSHADER_mtlShaderState *shState);
+
+/* Push render state changes that occurred within an actively rendering pass.
+ *
+ * This function maps to ID3DXEffect::CommitChanges.
+ *
+ * (mtlEffect) is a MOJOSHADER_mtlEffect* obtained from
+ *  MOJOSHADER_mtlCompileEffect().
+ * (state) is a pointer to the current shader state object.
+ */
+DECLSPEC void MOJOSHADER_mtlEffectCommitChanges(MOJOSHADER_mtlEffect *mtlEffect,
+                                                MOJOSHADER_mtlShaderState *shState);
+
+/* End an effect pass from the currently applied technique.
+ *
+ * This function maps to ID3DXEffect::EndPass.
+ *
+ * (mtlEffect) is a MOJOSHADER_mtlEffect* obtained from
+ *  MOJOSHADER_mtlCompileEffect().
+ */
+DECLSPEC void MOJOSHADER_mtlEffectEndPass(MOJOSHADER_mtlEffect *mtlEffect);
+
+/* Complete rendering the effect technique, and restore the render state.
+ *
+ * This function maps to ID3DXEffect::End.
+ *
+ * (mtlEffect) is a MOJOSHADER_mtlEffect* obtained from
+ *  MOJOSHADER_glCompileEffect().
+ * (state) is a pointer to the current shader state object.
+ */
+DECLSPEC void MOJOSHADER_mtlEffectEnd(MOJOSHADER_mtlEffect *mtlEffect,
+                                      MOJOSHADER_mtlShaderState *shState);
+
 #endif /* MOJOSHADER_EFFECT_SUPPORT */
 
 #endif /* MOJOSHADER_EFFECTS_H */