From 32c7d56e77a7e7ab2588b02f592d69e1b3049e24 Mon Sep 17 00:00:00 2001
From: Bernhard Liebl <poke1024@gmx.de>
Date: Thu, 2 Aug 2018 20:42:39 +0200
Subject: [PATCH] More general gradient matrix layout

---
 src/cpp/_interface.h    |  8 +++++++-
 src/cpp/shader/color.h  | 24 +++++++++++++++++++++---
 src/lua/core/shader.lua |  1 +
 src/lua/main.lua        | 22 ++++++++++++----------
 4 files changed, 41 insertions(+), 14 deletions(-)

diff --git a/src/cpp/_interface.h b/src/cpp/_interface.h
index 101c5f4..8e87287 100644
--- a/src/cpp/_interface.h
+++ b/src/cpp/_interface.h
@@ -161,9 +161,15 @@ typedef struct {
 	int16_t numColors;
 } TovePaintColorAllocation;
 
+typedef enum {
+	MATRIX_MAT3x3,
+	MATRIX_MAT3x4,
+} ToveMatrixType;
+
 typedef struct {
 	int16_t numColors; // to be removed
-	ToveMatrix3x3 *matrix;
+	float *matrix;
+	ToveMatrixType matrixType;
 	ToveVec4 *arguments;
 	uint8_t *colorsTexture;
 	int16_t colorsTextureRowBytes;
diff --git a/src/cpp/shader/color.h b/src/cpp/shader/color.h
index c72e0f0..a72a687 100644
--- a/src/cpp/shader/color.h
+++ b/src/cpp/shader/color.h
@@ -67,7 +67,7 @@ class AbstractPaintFeed {
 
 				if (gradient.arguments) {
 					if (gradient.matrix) {
-						float *m = &gradient.matrix[0][0];
+						float *m = gradient.matrix;
 
 						m[0] = 1;
 						m[1] = 0;
@@ -80,6 +80,12 @@ class AbstractPaintFeed {
 						m[6] = 0;
 						m[7] = 0;
 						m[8] = 1;
+
+						if (gradient.matrixType == MATRIX_MAT3x4) {
+							m[9] = 0;
+							m[10] = 0;
+							m[11] = 0;
+						}
 					}
 
 					if (gradient.arguments) {
@@ -127,7 +133,7 @@ class AbstractPaintFeed {
 		}
 
 		assert(gradient.matrix != nullptr);
-		paint->getGradientMatrix(*gradient.matrix, scale);
+		paint->getGradientMatrix(*(ToveMatrix3x3*)gradient.matrix, scale);
 
 		if (gradient.arguments) {
 			float s = 0.5f / gradient.colorTextureHeight;
@@ -193,7 +199,19 @@ class PaintFeedBase : public AbstractPaintFeed {
 	}
 
 	void bind(const ToveGradientData &data, int i) {
-		paintData.gradient.matrix = &data.matrix[i];
+		int size;
+		switch (data.matrixType) {
+			case MATRIX_MAT3x3:
+				size = 3 * 3;
+				break;
+			case MATRIX_MAT3x4:
+				size = 3 * 4;
+				break;
+			default:
+				assert(false);
+		}
+
+		paintData.gradient.matrix = data.matrix + i * size;
 		paintData.gradient.arguments = &data.arguments[i];
 		paintData.gradient.colorsTexture = 	data.colorsTexture + 4 * i;
 		paintData.gradient.colorsTextureRowBytes = data.colorsTextureRowBytes;
diff --git a/src/lua/core/shader.lua b/src/lua/core/shader.lua
index 7744bfc..f9c2614 100644
--- a/src/lua/core/shader.lua
+++ b/src/lua/core/shader.lua
@@ -286,6 +286,7 @@ local function newMeshFeedData(name, graphics, tess, usage, resolution)
 		alloc.numPaints * ffi.sizeof("ToveVec4"))
 	local gradientData = ffi.new("ToveGradientData")
 	gradientData.matrix = matrixData:getPointer()
+	gradientData.matrixType = env.mat3.type
 	gradientData.arguments = argumentsData:getPointer()
 	gradientData.colorsTexture = imageData:getPointer()
 	gradientData.colorsTextureRowBytes = imageData:getSize() / alloc.numColors
diff --git a/src/lua/main.lua b/src/lua/main.lua
index d65127b..6370956 100644
--- a/src/lua/main.lua
+++ b/src/lua/main.lua
@@ -71,10 +71,21 @@ tove.init = function(path)
 		rgba16f = love.graphics.getCanvasFormats()["rgba16f"],
 		mat3 = {
 			glsl = "mat3",
-			size = ffi.sizeof("ToveMatrix3x3")
+			size = ffi.sizeof("ToveMatrix3x3"),
+			type = lib.MATRIX_MAT3x3
 		}
 	}
 
+	-- work around crashing Parallels drivers with mat3
+	do
+		local _, _, _, device = love.graphics.getRendererInfo()
+		if string.find(device, "Parallels") ~= nil then
+			env.mat3.glsl = "mat3x4"
+			env.mat3.size = ffi.sizeof("float[?]", 12)
+			env.mat3.type = lib.MATRIX_MAT3x4
+		end
+	end
+
 	-- deepcopy: taken from http://lua-users.org/wiki/CopyTable
 	function deepcopy(orig)
 	    local orig_type = type(orig)
@@ -91,15 +102,6 @@ tove.init = function(path)
 	    return copy
 	end
 
-	-- work around crashing Parallels drivers with mat3
-	do
-		local _, _, _, device = love.graphics.getRendererInfo()
-		if string.find(device, "Parallels") ~= nil then
-			env.mat3.glsl = "mat3x4"
-			env.mat3.size = ffi.sizeof("float[?]", 12)
-		end
-	end
-
 	-- common attributes used by Command and Curve.
 	local _attributes = {
 		cp1x = 0,